Understanding that Russian is rather hardly available language for most polychaetologist and moreover they have so much to learn within Polychaeta, I have tried to prepare the English translation to make available my miserable book. But the English is not my mother tongue, so a lot of mistakes inevitably should be. The translation is not 'word by word', but rather literature. It was finished two years later than the book. Since my colleagues and I worked under a monograph on Arctic (within the same region as the book) Polychaeta. A lot of additions were made to the text of the book which was laid in the base of forthcoming monograph. Surely they should not be reflected in the English translation, but sometimes I cannot avoid it. Some corrections of mistakes were done also.
The book is not translated completely, but only the original parts.
Naturally small changes and emendations were made everywhere,
but if they were not principal (to my opinion) they were missed.
The same practice was followed even in cases where descriptions
are original (Glyceridae, Nereidae), but completely agree with
common senses of taxa. Diagnosis of families and genera were missed
also, if there were no principal changes). Such chapters as 'Taxonomic
features of Polychaeta', 'Fixation', 'Preservation of material',
'Investigation of material', 'System of Polychaeta', are common
also, so I suppose there was no reason for translation.
Preface to english translation 1
Preface 1
List of abbreviations 3
Key to families of polychaeta from the north polar basin 3
Phyllodocidae 7
Aphroditidae 7
Goniadidae 8
Nephtydidae 9
Amphinomidae 13
Euphrosinidae 13
Onuphidae 15
Pectinariidae 16
Ampharetidae 17
Terebellidae 25
This guide, as the next, preparing to press (including all others Polychaeta' taxa) is one part of the serial guide for students' extended practical work on bottom fauna of the USSR seas, founder of which was V.I.Zatsepin (Zatsepin, Rittich, 1979, 1982). However both are distinctly differ with their construction due several reasons.
First, Polychaeta fauna of Soviet seas is investigated worse Crustacea, Echinodermata or Bivalvia ones, especially it concern to the far eastern fauna, no more half of a full species composition of the last is known at the present time by our opinion. So here the fauna of the North Polar Basin is included only, many families of which are investigated comparatively well.
Second, for the time being there is no somewhat complete guide
on Polychaeta of the North Polar Basin (the same even more concern
to the Far-Eastern seas). The more complete guide on Polychaeta
of the North Polar Basin (Zatsepin, 1948) became antiquated since
finishing in writing and in reality is far not complete. Monograph
papers on separate taxa (Streltsov, 1973; Uschakov, 1972,1982;
Arwidsson, 1906; Gidholm, 1966; Fauchald, 1963,1974; Holthe, 1986
a; Jones, Hartmann-Schroder, 1985; Stop-Bowitz, 1941,1945 a,b,1948
and others) do not embrace all families, moreover most of them
are hardly available. So the guide firstly is supposed to fill
this lack.
4
Taking into account mentioned above, this guide embracing a whole presently known (from literature and our data) fauna of the North Polar Ocean from southern parts of the Norwegian and the Greenland seas to the Bering Straight. Unfortunately, a taxonomy of the most families is not in satisfactory condition even in such small area. So different families are given with a different degree of detailing: the keys are given to a species, a genera or absent. This gives to the guide unevenness character, that reflects a real degree of our knowledge of the ocean's fauna. Due a limit of book's room recently revised and/or comparatively rare families (Polynoidae, Sphaerodoridae, Paraonidae and others) are not given in details. In some occasion for a text reducing are not given descriptions of rare genera and species. To our sorry however even after these reducing the size was too large, so after a long meditations, all date on biology and distribution of species were excluded. The overall picture of distribution of arctic Polychaeta were described earlier (Jirkov I.A., Mironov A.N., 1985. Contribution to zoogeography of arctic polychaetes. - Transactions Shirshov Inst. ocean., Acad. Sci. USSR Press, v.120, pp.137-151 (in Russian). It is supposed to give a full and detailed descriptions of this matter later. Diagnosis of pelagic and parasitic taxa were excluded also. For the same purpose, some taxonomical results were published separately (Jirkov, 1982, 1985, 1986 á,í,ó; Jirkov, Ermolaev, 1989; Sikorski, Jirkov, Tzetlin, 1988; Tzetlin, Jirkov, Markelova, 1983). References are given in due places.
Descriptions and figures are mainly original and based on collections of Hydrobiology Department of Moscow States University, Zoomuseum of MSU, Zoological Institute in Leningrad. The author ought to thank his colleagues helping with advices, materials and collections: P.V.Uschakov, A.B.Tzetlin, N.V.Kucheruk, A.V.Sikorski, T.A.Britaev, V.V.Chlebovich, V.N.Koblikov, R.Ya.Levenstein, V.V.Potin, L.A.Rittich, V.G.Averintsev, G.N.Buzhinskaya, A.V.Rzhavskiy and T.Holthe. A lot of help was given by my former students: M.V.Kolesnikov, A.K.Karamyshev, E.B.Buljugina, A.V. and I.G.Ermolayevs, E.K.Kuprianova. A separate thank to M.V.Ljubimov, giving invaluable technical help.
Without any doubt the book isn't free from lacks. I'll be very
thankful to all who giving me notice in any form at the address:
119899, Moskva, MSU, Biological faculty, Department of Hydrobiology.
18
The keys are brackets, but when polythomial instead usual dichotomous subdivision can be it is done for the simplification. Syntaxes bears additional information: first sentence (up to point) includes diagnostical characters, second sentence (if present) includes characters making identification easier, but they are not strictly diagnostical (i.e. more or less overlapping, not always existing and so on). Characters using in the keys are not always diagnostical for faunas outside the North Polar Ocean. While preparing keys we suppose that their main purpose is the help in an identification rather than a conspectus of a phylogeny. I have tried to use and to limit with only characters visible under enlarging less 50 x and which do not required preparing of slides. If given in the key Latin name of a taxa doesn't accompany with author's name and year of publication, there is a diagnosis of the taxa below. Otherwise diagnosis of the taxa is absent. Genera within a families and species within a genus are in alphabetic order.
Diagnosis of all taxa (contrary to characters in keys) concern
to whole taxon.
19
AS - abdominal setiger
SS - segment - setiger
S - segment
TS - thoracic setiger
(modified)
28
Descriptions of the species and diagnosis of more high taxa follow
with some changes to Uschakov's monograph (1972).
38
Prostomium is rounded anteriorly, with two large eyespots. There is a pair of processes on its posterio - lateral part. This processes usually are bifid, in small specimens (up to 10-15 mm length) they are enter, in large specimens (longer 30 - 40 mm) an amount of lobes can achieve 7. Antennae are large, thick, spindle- shaped or somewhat flattened, unpaired is distinctly bigger others. Two anterior S fuse with the next dorsally. Ventral cirri of 3rd S are similar to next. Peristomial cirri are similar to antennae on their form, but larger. Setae start from the 2nd S. Dorsal cirri are very large, thick, distinctly cover dorsum, two times wider the length, very easily missed. Ventral cirri are transversely - oval, distinctly longer parapodial projections. Up to 60 mm length, up to 115 SS. Colored (in alcohol) light brown, dorsal cirri dark-brown.
Remark. The main difference between N. foliosum, N. imbricatum, N. americanum is a degree of prostomial processes' branching. Investigated specimens show that variation of the character is rather more than it's taken earlier. That is why these three species are probably synonyms.
42
(= Hermione Blainville, 1828 preoc.pro Lepidoptera Meigen, 1800). The only species H. hystrix was mentioned from the ocean (see Remark 2. to Laetmonice uschakovi).
46
Palps are very long, attached behind and laterally to a papillate lobe. The base of this lobe covers with two short processes and with ceratophore laying between and above them. Ceratostyle is very long, slim. There are a pair of unpigmented ommatophores laterally to antennae bases. There are 17 (rarely 18) pairs of brown elytra on 2nd, 4th, 5th and further back through single SS up to 35th, further back through two SS up to 27, where there is 17th pair of elytra, further back there are 3-5 SS, and 18th pair of elytra can developed on 40th SS. Parapodia of the last SS reduced. Notosetae of elytra - bearing SS are span-like protective setae and of cirri-bearing SS are harpoon shaped and comparatively short dorsal feltage setae; sometimes they can produced poor developed dorsal feltage setae, which doesn't cover even parapodia. There are few neurosetae, theirs tips with unilateral fringle and 1 (rarely 2) spurs. Specimens of 19-63 mm length have 40-42 SS.
Etymology. The species is named after Pavel Vladimirovich Uschakov.
Material: Holotypes from st. station.19 R/V"Tunetz", cruise 105, 70°58' N, 21°23' à, depth 165-170 m, collected July 02.1978, deposed at Zoomuseum of MSU N Pl 772, 79 paratypes from SS-W part of the Barents sea and near laying parts of th Norwegian sea collected at depth 155-525 m, at bottom temperature 2.2...7.0°Ñ (18 samples, deposed at Zoomuseum of MSU N Pl 773...Pl 790).
Remarks. 1. Species was discovered, but not described by P.V.Uschakov (1982). 2. An information about a distribution of L.filicornis within the Barents sea (Zatsepin, 1948) in reality concern to L.uschakovi, while a distribution of L.filicornis s.str. described in this book under Hermione hystrix (Savigny, 1818). The last species by all probability doesn't occur within the North Polar ocean. It seems, that many mentions of L.filicornis from the North Polar ocean in reality concern to L.uschakovi. The last species occurs also near Newfoundland (our data) and to the south from Iceland (Detinova,1985 b).
Differ from previous species with more lighter, almost uncolored elytra, poorer developed feltage setae, comparatively longer harpoon shaped setae, twice longer body's width without parapodia, poor developed processes of ceratophores and, especially, with presence of only 15 pairs of elytra and no mere than 34 SS (up to 36 SS according to Uschakov,1972). Length up to 30 mm (40 mm according to Uschakov,1972).
Remark. See remark 2. to L.uschakovi.
Micrognaths: absent ventrally, near 20 dorsally. Secondary segmentation absent. Ca. 35 anterior SS with uniramous parapodia. Parapodia of posterior biramous region with small notopodium with few setae. Presetal lobes of parapodia of anterior region and neuropodium of posterior region conical. In alcohol colorless. Up to 60 mm long.
Micrognaths: absent ventrally, near 20 dorsally. Secondary segmentation absent. Ca. 35 anterior SS with uniramous parapodia. Parapodia of posterior biramous region with small notopodium with few setae. Presetal lobes of parapodia of anterior region and neuropodium of posterior region with mucronate tip. Color in alcohol: light rings along segment margins and dark-brown rings running through parapodia and broken above and under parapodia. Up to 45 mm long.
Key emended according data of Rainer (1989,1990) and our new data
Prostomium with 4 antennae, interramal cirri involved, acicula hooked, pharynx with 14-22 longitudinal rows of papillae.
There are 14 longitudinal lows of subterminal papillae, each of
12-18 ones, besides that can present extra subterminal papillae,
73
located irregularly or forming short rows. Proximal pharynx surface smooth. Presetal lobes of noto- and neuropodium shorter acicular, acicular - sharply-conical, postsetal notopodial lobes bilobed, upper part equal to lower in middle SS and much less than lower in posterior; neuropodial are simple. A form of parapodia doesn't almost change caudally, only the most posterior parapodia (less 10) are reduced. Interramal cirri in 246 investigated specimens start at 10th-23rd SS (in Norwegian specimens according to Fauchald(1963) at 8-15 SS). The cirrus starts at average later in high Arctic's, especially in deep-water's specimens than in specimens from the Barents sea, and moreover, than in boreal (from Norwegian) ones. An interramal cirrus caudally at first increased in size, then slightly reduced, but the first and the last ones are much greater notopodial cirrus. A serial number of last SS with an interramal cirrus varies within a wide limits (22nd-46th), and an amplitude of a variation is grater in specimens from the high Arctic. Limits of variation of serial number of SS where interramal cirrus starts and where it ends overlapping ,specimens without interramal cirri can probably exist, especially in the deep high Arctic, at least one specimen with the only cirrus at 23rd SS was caught. Aglaophamus rubellus,puc.15 1 There are 14 longitudinal lows of subterminal papillae, each of 22-23 ones. Proximal pharynx surfaces smooth.Neuropodial peristomial cirrus more than twice longer next ones. Noto- and neuropodial presetal lobes shorter acicular ones, bilobed; acicular are sharply conical. Postsetal lobes: notopodial - deeply bilobed, upper part much larger lower, neuropodial - bilobed, upper part minute. Neuropodial cirri are very diagnostical for the species: they are foliaceous from ca. 15th SS. Notopodial (not interramal!) cirri are foliaceous also. Interramal cirri from 2nd-3rd SS, according Fauchald they are present even onto last SS.
Small Nephtys and Aglaophamus is included here. There are no diagnostical morphological characters of the genus independing on size.
A description of specimens from shallow (4-8 m) depth of the White sea. There is unpaired dorsal papilla. Noto- and neuropodial pre- and postsetal lobes are rudimental, acicular are conical. There is a pair of black pigment spots on the dorsum of III SS between or slightly in front of parapodia (dissapear in alcohol). There is a circle bond of small red-brown spots on a pygidium. An anal cirri is ventral and long. Interramal cirri are straight or slightly involved, start from 5th-7th SS (among 111 specimens from 5th in 2, 6th - in 105, 7th - in 4). A serial number of last SS with an interramal cirrus slightly (Pearson's correlation coefficient Ä,38, but a probability of its difference from 0 more 99%) correlates with total amount of SS; in specimens longer 3 mm it is absent behind 12th-18th SS, usually behind 14th-15th SS. Thus interramal cirri are present on 7-13 SS (usually 9-10).
The species easily differs form juvenils of others co-existing Nephtydidae species with small number of SS with interramal cirri.
Remarks. 1. Specimens form the White sea from the depth more than 30 m differs from shallow-water ones with later appearance of interramal cirri, from 6th-9th SS (among 70 specimens from 6th - in 2, 7th - in 42, 8th - in 24, 9th - in 2) and its earlier disappearing (behind 10th-13th SS). Despite a character of a geographical variation is somewhat similar to A. malmgreni (see above), the very variation doesn't look like gradual one, as in A. malmgreni. Perhaps shallow- and deep- water populations belong to different species. (Now I think it so: shallow water is M.neotenus while deep water is M. minuta s.str. - I.J.,August 1990). 2. Despite M. minuta was described from the Barents sea, there was only two specimens from the sea (69°55' N, 42°00' E, 125 m and 74°30' N, 50°23' E, 136-138 m) both have interramal cirri on 7th- 12th SS, and 5 mm long one consists of 24 SS, other 26 SS. 3. V.I.Zatsepin (1948), P.V.Uschakov (1955) and A.B.Tzetlin (1980 á) pointed out that interramal cirri start from 10th SS. There were no one such specimens with such late appearance of interramal cirrus among 182 investigated, but in 3 it finished at 10th SS. 4. Aglaophamus neotenus, jugging to original description have no difference with shallow- water the White-sea's M. minuta. 5. M. minuta sensu Pettibone, 1963 differs with later start of interramal cirrus (from 12th-14th SS), undoubtedly it belong to a different species.
Remark. See remark to N.longosetosa.
An unpaired dorsal subterminal papillae is present. There are 3-5 subterminal papillae per row. Proximal pharingeal papillae are conical, pointed. Acicular lobes especially notopodial are distinctly bilobed at least at 10-15 first SS. Presetal notopodial lobes are rudimental, neuropodial ones are small, but distinct. Postsetal notopodial lobes are shorter or equal to acicular, notopodial are somewhat longer acicular. Parapodia reduced caudally, acicular lobes became rounded, then almost pointed, presetal lobes are almost disappear. postsetal lobes became similar to acicular with a shape and a form. Interramal cirri start at 8th- 12th (rarely at 7th) SS, the last SS with an interramal cirrus longer notopodial is usually 30th-40th from the end, only in very large specimens (longer 150 mm) it is long further back.
Remark. Earlier N. ciliata was mixed with N. pente.
According to descriptions of N. ciliata of Pettibone (1963)
and Hartmann- Schroder (1971), they dealt with both species. Descriptions
of Zatsepin (1948), Uschakov (1955) and Tzetlin (1980 á)
are not enough detailed for taxonomical conclusions (suitable
for both species). However, jugging to the fact that N.pente
is common within areas embracing with these monographs (our data),
they dealt with both species.
77
Remark. The species is similar to N.caeca. They can be easily differ with a pharynx, but the last is not turned out always. In this case if one wouldn't like to dissect a worm, it is very useful for it a degree of a posterior S in interramal cirri development and somewhat a middle body postsetal neuropodial lobes form. N.caeca and N.longosetosa, undoubtedly have mixed earlier, so data, concerning to these species should be checked. In investigated material from the Barents sea N.longosetosa are more common than N.caeca, and within the White Sea the last didn't discovered at all.
78
An unpaired dorsal subterminal papillae is present, slightly greater others. There are 5-6 very small subterminal papillae per each row. Proximal pharingeal papillae usually are absent, sometimes there are some, more often in large specimens. Presetal lobes are rudimental, acicular are evenly rounded, postsetal are slightly sorter acicular. Posterior acicular lobes are conical, others are rudimental. Interramal cirri start from 5th-20th, usually from 8th-10th SS. The first are very small caudally increases in size very slow, so starting SS can be determined hardly. Usually interramal cirri are fully developed from 25th-27th to 40th SS, further back decrease and disappear behind 55th-60th SS. A typical fully developed cirrus is foliaceous, flattened, completely or only at a base, but sometimes specimens with only few foliaceous cirri or even absolutely without them occur.
Remark. There is no unpaired dorsal subterminal papillae in N.paradoxa sensu Uschakov,1955 (see puc.69 A), so it probably belongs to another species.
An unpaired dorsal subterminal papillae is present. There are 4-5 subterminal papillae per each row. Proximal pharingeal papillae are flattened and blunt, but in small specimens (length of 10-20 mm) they are conical, identical to corresponding papillae of N.ciliata of the same size. Interramal cirri start from 5th-6th SS. The last SS where they longer notopodial ones is 6th-15th from the back.
Remark. Describing by me N.zatsepini, is by my opinion a junior synonym of N.pente.
Proximal pharynx smooth. Noto- and neuropodial presetal lobes are much shorter acicular. Notopodium; acicular lobes with deep incision near aciculum, the lower part distinctly longer upper; neuropodial - oblique, sometimes with small incision. There is distinct lobe above aciculum at 10th and neighboring SS. Caudally this lobe become less distinct rather quick and at ca. 20th-3-th SS acicular lobe simply oblique. Noto- and neuropodial postsetal lobes are much longer acicular. Interramal cirri from 6th SS, at first no longer than notopodial, then angle and become equal to notopodial at ca. 10th SS from behind. Up to 220 mm length.
Prostomium with 5 identical antennae, extend on 1st SS. Noto- and neuropodial cirri of 1st SS long and slim, others - several times as shorter. Wide, fanlike flattened transversely branchiae start form 4th SS and present on 2-7 SS. Small specimens consisting of 13-15 SS have minimal amount of branchiae, but specimens consisting of 12 SS can already have as much branchiae as large specimens from the same locality [According to Pettibone(1963) branchiae can start from 3rd SS and present on 12 SS]. Setae capillary, serrate, besides there are 1-2 hooks in each Notopodium of 1st SS, this hooks shorter and stronger than others but hardly discovered because are very translucent. Up to 20 mm length and 43 SS.
Remark. Pseudeurythoe hemuli, is known with 2 specimens from Sognefjord (Norway at 61°N). According to original description it differs from Paramphinome jeffreisii only with absence of hooks in 1st notopodium. This setae are less than overlooked by him pseudoacicular ones of Nothria hyperborea (Jirkov, Ermolaev, 1989), so validity of P. hemuli, by our opinion needs in corroborating.
Each Notopodium with 6-8 branchiae, 3 (rarely 2) from which are between inner and middle dorsal cirrus. Branchiae cirriform or looks like pair of cirrus with common base, rarely there are extra branches, branches never claviform. Notosetae of two kinds: 1) longer, straight, with short spur smooth, distinctly longer than branchiae and 2) shorter, unequally bifurcated, curved toward the shorter branch, serrate on inner side of branches; there are very a little setae of the last type. Neurochaetae of the same length as longest notosetae. Up to 26 mm long and 15 mm wide, including setae, 24-33 SS.
Remark. Specimens from the middle part of the Barents sea and a slope of the Norwegian sea differ from specimens form boreal regions of the Norwegian sea [identical with described by Pettibone(1963)] with less branched branchiae (described above) instead dichotomously branched with 2-4 (1-12) branches; much wider distance between notopodium in the middle of the body, achieves 1/3 of body width. Remark. Searching for undoubtedly useful published recently monographs on Eunicemorpha (Jones, Hartmann-Schroder, 1985) in the USSR have not been successful.
There is only species in the ocean: M. bellii
Antennae are irregularly annulated. Branchiae start from the 3rd (in 2/3 of worms) or from the 4th (in 1/3 of worms) SS, the greatest branchiae usually twice shorter dorsal cirrus and only in hudge specimens (wider 6 mm) are nearly equal to it. An amount of branchial branches and branchial S authentically enlarge with body size. In specimens with a width ca.4-5 mm branchiae are absent back to 46th-49th SS. Branchiae are of usual pectinate type, with up to 4 branches. Acicula are black. Fresh specimens brightly red, whilenn storaging color missed.
Remarks. 1. see remark to Eunice norvegica. 2. as gender of Eunice is famine, the most correct ending is -a, instead -us, as in original description.
Antennae are smooth to irregulary annulated. Branchiae satrt from 6th (in 1/3 of worms) or from 7th (in 2/3) SS to the end of a body. The most developed branchiae of a large specimens are near equal to a dorsal cirrus. Branchiae are of usual pectinate type, as in previous species, but sometimes can present secondary branched branchiae. A total amount of branches in such branchiae can achieve 21. Not taking into account aberrant branchiae, an amount of branches authentically enlarges with a body size and in worms with width 5-6 mm acheves 8. Acicula are black. Worms are yellow-brown or light-brown.
Remarks. 1. Jugging to investigated materials from the Barents sea (materials of V.I.Zatsepin to our sorry missed), E.norvegica sensu Zatsepin,1948 fully identical with E.pennata. E.pennata is very usual in the SS-W of the Barents sea, while E.norvegica didn't collected there, however it can inhabit spongial community within it. Streltzov (1966) and Petrovskaja (1962) more probably used Zatsepin's guide while identification, in any case all worms, identified by them as E.norvegica really are E.pennata. 2. Eunice norvegica sensu Hartmann-Schroder,1971 mixed feature of E.norvegica s.str. and described three years later E.dubitata.
Antennae are irregularly annulated. Branchiae started from 3rd SS always, the most developed twice longer a notopodial cirrus. An amount of branchial branches and branchial S for sure enlarge with body size and in specimens with a width 3.5 mm achieves 14. In worms wider 2 mm branchiae are absent back to 40th SS. Acicula are light-yellow. Worms are yellow-brown, light-orange, without pattern or with it as black subacicular spots near parapodial bases, sometimes specimens occur with metallic green spots.
Remark. See remark 1 to Eunice norvegica.
The family includes near 240 species, joined into 22 genera (Paxton, 1986). For sure there are 8 species and 5 genera in the Ocean. Besides, it's mentioned from the ocean three species: Nothria conchylega, N.britannica and Kinbergonuphis arctica. The first two are probably synonyms of two described below species of the genus Nothria (Jirkov, Ermolaev, 1989), the third is incertae sedis due the missing of types and unsatisfactory description, it is admissible that it is synonym of Nothria hyperborea.
A taxonomy of the family was re - bilded for the last years, so
old descriptions and data on a species biology and distribution
couldn't be recommended for use.
The first pair of parapodium is much enlarged. The second and third are slightly enlarged. Ventral cirrus is Ò¿½Remark (missed in original). Specimen of ?Hyalinoecia tubicola (Annenkova, 1952 b) is in reality Paradiopatra pauli (N.V.Kucheruk, pers. com. and my own observation).
for details see Jirkov, Ermolaev (1989)
Remark. N.V.Kucheruk re-investigates holotype of Onuphis africana and discover, that it is identical to specimens identified by Ermolaev and me (Jirkov, Ermolaev,1989) as Nothria atlantica (N.V.Kucheruk, pers.comm.).
Ventral cirri cirriform onto anterior 1-3 SS, further back gradually become pad-like. All presetal lobes digitiform. Branchiae from 5th-7th up to 40th-48th SS, onto 9th-18th SS they are most branched, amount of branches increase with worm size and achieves, in juvenils (up to Ä.75 mm wide) branchiae absent. Up to 2.5 mm wide without parapodia and 120 mm long.
Remarks. 1. P. pauli cannot be differed from P. quadricuspis with amount of anterior SS with cirriform ventral cirri, S of appearing of branchiae, amount of branchial branches, comparative length of postsetal lobe and cirri of 1st SS, comparative length of antennae and amount of rings of ceratophores. Nevertheless, sure absence of Paradiopatra between areal of these two species shows by my opinion that they are distinct. P. pauli occurs within high Arctic regions (northern parts of the Chuckchee sea, 55-470 m). Probably finds of P. quadricuspis from a slope of the Beaufort sea (Biljard,Carey, 1980) concern to P. pauli. P. quadricuspis is known for sure onto shelves and slope of the North Polar ocean near Iceland, Shetlands and along Norwegian coasts up to Bear Isl., almost exclusively within the regions influenced with the warm North-Atlantic stream. 2. See remark to Hyalinoecia tubicola.
Paleae (9-15 on each side) with long capillary tips, turned dorsally. 17 TS, 13 with neuropodium, last notopodium minute and hardly visible. 8-10 anal hooks on each side, slender than in P.hyperborea. First three S of scaphe bears cirri. Anal tongue blunt-rounded, with small anal cirrus. Up to 40 mm long. Tube light brown, build with small sand grains (very similar to P.hyperborea, but never rusty, as in the last) or tube consists of fragments of spiculae, set transversely.
Paleae (7-10 on each side) with blunt rounded tips, only most lateral (young) setae have pointed tips. 17 TS, 12 with neuropodium, last two notopodium minute and hardly visible. All S of scaphe bears lobes. Anal tongue blunt-rounded, with short anal cirrus. Up to 52 mm long. Tube build with large (several times larger than in P. auricoma, P. hyperborea and P. koreni sand grains black and light gray (mixed).
Paleae 9-13 (usually 11-12) on each side) with long capillary tips, turned dorsally. Paleal setae light brown, but usually they cover with rusty sediment. 17 TS, 12 (rarely 11) with neuropodium, last two notopodium minute and hardly visible. 3-9 (usually 5-9) anal hooks on each side, slender than in P.hyperborea. Scaphe with 6 lobes at margins. Anal tongue blunt-rounded, somewhat shorter width, anal cirrus small or absent. Up to 55 mm long. Tube consists of small translucent sand grains, cement of tube light brown (as in P.auricoma) or usually rusty-brown.
Paleae (10-15 on each side) with long capillary tips, turned dorsally. Paleal setae light brown, as in P.hyperborea, but almost do not cover with rusty sediment and so look lighter. 15 TS, 12 with neuropodium. There are two apodous S before scaphe. 2- 7 anal hooks on each side. Scaphe elongate-oval. Anal tongue rounded, somewhat shorter width, anal cirrus small or absent. Up to 50 mm long. Tube mainly consists of small translucent sand grains, cement of tube light gray almost white.
Dorsal brim smooth. Second S ventrally with dentate lobes. Paleae (8-11 on each side) with blunt rounded tips, turned dorsally. 17 TS, 14 with neuropodium. Last noto- and neuropodium only slightly less than previous, very well visile. 8-10 anal hooks on each side. Scaphe with 6 papillae at margins. Anal tongue long and slim. Up to 15 mm long.
100
It's known more than 200 species of the family, joined into approximately
70 genera (15-20 from which, by my opinion should be turned to
synonyms), and 3 subfamilies: Melinninae, Ampharetinae and described
recently Uschakoviinae Holthe, 1986 b. The last subfamily is monotypic.
According to the original description of Uschakovius enigmaticus
Laubier, 1973, this species is Chaetopteridae. There are 20 genera
and 31 species in the ocean.
Slightly modified
Monotypic genus: Y.pteropoda Holthe, 1986
There is only species within the Ocean: M.bathyalis
Monotypic brackishwater genus: A.romijni
There is only species within the Ocean: L.fragilis
Monotypic genus: A.macroglossus
Monotypic genus: M.laubieri
There is only species within the Ocean: E.vanelli
There is only species within the Ocean: A.sibirica
Monotypic genus: Z.rittichae
Prostomium trilobed. Branchiae in two groups, branchiae of each group in two transverse rows. All branchiae within group and anterio - medial of different groups fuse at bases. All branchiae of the same shape and uniform. 3rd S with small conical lobe near notopodium. Dorsal hooks slightly curved. There is dorsal brim between notopodia of 5th SS with 8-16 identical dents, it achieves notopodia of 4th SS. Sometimes there is extra brim before notopodia of 6th SS, its size varies from slightly developed to almost equal to anterior, this brim is dentate also. Very seldom third brim begin to show more caudally. Neuropodia of 1st-4th SS with capillary setae, from 5th with pectinate. Notopodia form 3rd to 18th SS, first pair very small (can absent), second somewhat bigger. Up to 50 mm long. Tube thick-walled, muddy, without incrustations.
Prostomium trilobed. Large buccal tentacle similar to Melinnopsis arctica sometimes present. Branchiae in two groups, three branchiae of each group in oblique transverse row, fourth is before inner. All inner branchiae fuse on 1/3-1/2 theirs length, others - only at bases. All branchiae of the same shape and uniform. 1st S with broad ventro - lateral collar, conical lobe of 3rd S absent. Dorsal hooks strongly curved. Dorsal brim irregularly serrate, size of dents varies, the biggest have additional dent on each side. Neuropodia of 1st-4th SS with capillary setae, from 5th with pectinate. Notopodia form 3rd to 18th (rarely 17th) SS, first pair very small. Up to 50 mm long, up to 50 and more SS. Tube with thinner wall than in M.cristata and M.palmata, from uniform fine mud and detritus, anteriorly with more or less numerous incrustations of shell fragments, parts of leaves, tubes of Spiochaetopterus, stones, set perpendicularly to tube surface (similar to tubes of Sosane gracilis and Euchone analis).
Description of specimens from the Black sea. Prostomium trilobed. 8, rarely 10-12 identical buccal tentacles. Branchiae in two groups, three branchiae of each group in oblique transverse row, fourth is before inner. All branchiae within group and anterio - medial of different groups fuse at onto 1/3-1/2 length. All branchiae of the same shape and uniform. 2nd S with ventral collar. Dorsal hooks very long, slightly curved (protruding above surface part are similar to M.cristata. Dorsal brim smooth, waved or with blunt small dents. Neuropodia of 1st-3rd SS with capillary setae, from 5th with pectinate, onto 4th absent. Notopodia form 3rd to 18th SS, very small, without parapodial projections. Anterior AS with rudimental notopodia, posteriorly slowly reducing. Up to 55 mm long. Tube thick-walled, muddy, without incrustations, similar to M.cristata.
Remark. 1. M.palmata doesn't mention from the Ocean, but probably occurs in the Norwegian sea. 2. M.islandica, according to the original description, doesn't differ from M.palmata.
3-4 pairs of smooth branchiae. There are no dorsal ridge and hooks.
Remarks. 1. Hartman (1969) and following her Fauchald (1977) emended genus' diagnosis without any reason for. They included into the genus only species with dorsal ridge and without dorsal hooks. However, as there are no both dorsal ridge and dorsal hooks in type species of Melinnexis - M.arctica, thus this emendation can not be accepted. But moreover for the species of Melinninae without dorsal hooks and ridge (i.e. for Melinnexis s.str., non Hartman, 1969) a new genus Amelinna Hartman, 1969 was established. This genus should be counted as a junior synonym of Melinnexis s.str. 2. Melinnexis s.str. was quite correctly turned by Holthe (1986 á,b) into a synonym of Melinnopsis McIntosh, 1885. 3. Melinnopsides Day, 1964 differs from Melinnopsis with presence of only 3 instead 4 pairs of branchiae. However, amount of pairs of branchiae varies within species (see description of Melinnopsis arctica below), and cannot be used for generic separation.
Prostomium does not divides onto lobes, longitudinally folded. 3-4 pairs of branchiae into 2 groups: anterior inner branchia of each group twice wider and distinctly longer; others form oblique row, outer is on the same level as the biggest, inner (can absent) right behind the biggest. Neuropodia of 1st-4th SS with capillary neurosetae, from 5th with pectinate. Notopodia from 3rd to 16 SS, onto 3rd very small. Abdominal rudimental notopodia absent or slightly developed onto anterior AS. Anal cirri absent. Tube cylindrical, slowly tapering backwards, dense, thick-walled, detritus, anterior half incrusted with foraminiferae, sand grains, fragments of tubes of Spiochaetopterus. Remark. I investigated all syntypes of M.somovi and M.arctica. The only difference between them is the amount of pairs of branchiae: 3 in syntypes of M.somovi and 4 in M.arctica. There is individual variation of this character. I've got specimens with 3 of branchiae at one side of worm and with 4 at another (puc.21 5). That is why M.somovi should be counted as junior synonym of M.arctica.
4 pairs of branchiae into 2 groups, separated with distance equal to group width. Abdomen very short, of 8 (very seldom 9) AS with large rudimental notopodia. Pigidium with two thick anal cirri and several rounded papillae. Up to 10 mm long. Tube characteristic: soft, detritus, thick anteriorly, flat, somewhat rounded anteriorly and fast, but gradually tapering backwards.
Branchiae into 2 widely separated groups. Two branchiae of each group are in transverse row, other two into longitudinal row behind first two. Paleal setae in 1,5-2 times shorter notosetae of 1st SS. Notopodia without cirri. 19-23 AS with small globular rudimental notopodia, slowly disappear caudally. 2 long anal cirri. Up to 35 mm long. Tube is characteristic: flattened, slowly tapering backwards, »½AmphareteThere are 22 species, within the North Polar Ocean at least 8. From this number A.lindstroemi, A.balthica Eliason, 1955 and 1-2 undescribed yet species form compact group called here A.gr.lindsroemi, this group needs in taxonomical investigation. Besides A.eupalea Chamberlin, 1920, A.johanseni Chamberlin, 1920, A.reducta Chamberlin, 1920 were described from the Ocean, but so unsatisfactory that they should be taken as insertae sedis till types will be re-investigated.
Distance between branchial groups equal to 1-2 diameters of branchophores. Paleal setae (10-30 on each side) longer most developed notosetae, but of the same width; turn anteriorly they distinctly project from anterior margin of prostomium. Their tip is long capillary. 12 AS. Abdominal rudimental notopodia absent. Neuropodia with cirri at upper angle, very long onto usually 14 last SS, onto forthcoming much shorter, hardly visible. Pigidium with two long lateral cirri and numerous long cirriform or rounded papillae, rarer lateral cirri are not longer others, but distinctly thicker. Up to 80 mm long. Tube thick, straight, cylindrical, muddy and sandy with a thin lines of secretion.
Remark. Uschakov (1955) said nothing about neuropodial cirri which are the most characteristic for A.acutifrons. Cirri did not pictured at a figure of the very species in his book. It seems he dealt with another species. It is interesting that at a picture of A.acutifrons in Hartmann-Schroder (1971), following to Uschakov (1955), this cirri were added.
Distance between branchial groups less diameter of branchophore. Three branchiae of each group in an oblique row, forth are just behind middles of each group. There are two small nephridial papillae medially from the base of inners branchiae. Paleal setae numerous (more 20), distinctly shorter most developed notosetae, but of the same width. Their tip is rather sharply turn into long capillary. 12 AS. Abdominal neuropodia from 4th AS with short blunt or slightly pointed dorsal neuropodial cirrus. Up to 75 mm long.
Remark. A.crassiseta was turned into synonym of A.reducta by Uschakov (1950). This probably was accepted by Annenkova (1952 b) (paper was published after her death). However nor P.V.Uschakov, neither N.P.Annenkova had not investigated types specimens of A.reducta. Original description of A.reducta are not satisfactory, but it was mentioned there that each paleal group consists of 5-6 setae. This undoubtedly shows that A.reducta and A.crassiseta are different species.
Distance between branchial groups narrower diameter of branchophore or absent. Paleal setae (12-16 on each side) much longer and thicker most developed notosetae; turn anteriorly they achieve anterior margin of prostomium. Their tip shortly pointed (often point is broken). Up to 50 mm long. Tube cylindrical, thick,
Distance between branchial groups is equal to diameter of branchophore or almost absent. Paleal setae (15-18 on each side) much longer and thicker most developed notosetae; turn anteriorly they achieve anterior margin of prostomium. Their tip shortly pointed (often point is broken). 17-18 AS (in A.goeesi braznikovi Annenkova, 1929 from the Ochotsk sea 16 AS). Up to 50 mm long. Tube thick, muddy often is incrusted with foraminiferae, fragments of shells or needles of sea urchin.
We include into this group all Ampharete with 12 AS, paleal setae larger most developed notosetae, with tip gradually turn into long capillary and without neuropodial cirri. As it was mentioned above, A.lindstroemi, A.baltica Eliason, 1955 and 1-2 undescribed yet species belong to this group. Unfortunately, available material is not enough to taxonomical investigation of the group.
All branchiae are in the only transverse line without separation. Paleal setae longer most developed notosetae, but of the same width; turn anteriorly they achieve anterior margin of prostomium. Their tip gradually turn into long capillary. 26-28 AS, first 2-3 AS with flattened rudimental notopodia, larger than thoracic ones, but without setae. Up to 50 mm long.
Prostomium more or less pentagonal, with a pair of longitudinal ridges in the middle of anterior part, slightly projecting further anterior margin, where they slightly disperse. There are two transverse ridges at their base, gather in the middle under blunt angle. Theirs anterior part pigmented. There is band of more or less numerous small eyespots before transverse ridges or eyespots absent. Paleal setae (8-20 on each side) much bigger best developed notosetae, slim, with tips gradually turned to long capillary. Two group of branchiae separated with distance equal to diameter of branchophore. Notopodia with globular cirrus at outer angle. 15 AS. Abdominal neuropodia narrower toracic, with distinct long dorsal cirrus. Rudimental notopodia distinct, with almost globular cirrus on stem. Pigidium with two long anal cirri, without anal papillae. Up to 43 mm long. Tube thin-walled, without incrustations.
Prostomium similar to A.gunneri, but without eyes and pigmentation. Paleal setae (8-16 on each side) much bigger best developed notosetae, thick, with blunt tips. Notopodia (excluded 1st pair) with globular cirrus. 15 AS. Rudimental notopodia present. Abdominal neuropodia with short dorsal cirrus. Pigidium with two long anal cirri, without anal papillae. Up to 75 mm long. Tube thick-walled (thickness of wall is eqaul to inner diameter), muddy, rather friable without incrustations.
Prostomium and branchiae as in A.ninonae. Paleal setae loner best developed notosetae, similar to A.gunneri, but more mucronate. Notopodia (excluded 1st pair) with globular cirrus at outer angle. 19 AS. Rudimental notopodiae present. Abdominal neuropodia with short dorsal cirrus. Pigidium with two long anal cirri, without anal papillae. Very characteristical sencondary segmentation: all S, TS (with exception of some anterior) and AS are broad convex ring devided with narrow furrow onto 2; posterior run through parapodia, anterior less convex, especially onto torax. Segmental rings separeted with furrow equal to near half of ring. Up to 75 mm long.
Prostomium almost tetragonal, anteriorly envenly rounded, almost the same width as the rest of body, laterally turned ventrally, its posterior margins glandular, often marked with laghter color. Branchiae into two very widely seperated groups, distance between them is more than the width of a group. Two branchiae of each group are in transverse row, third somewhat longer, just behind inner. Anterior TS much shorter thw width, posterior - 2-3 times longer. AS numerous (usually 24-30). Neuropodial cirri and rudimental notopodia absent. Pigidium with two lateral cirri and numerous rounded papillae. Up to 45 mm long. Tube is very characteristical: cylindrical, slim and long (up to 160 mm long while width is 1mm), do not tapering to any end, muddy, thin-walled, with transversal prominent rings or translucent lines instead rings, usually both are present on one tube in different parts.
Lower lip embraces prostomium dorso-laterlly, extends anteriorly further anterior margin of prostomium. Anteriorly lower lip foled, ventrally with longitudinal grooves. Paleal setae minute, 2-3 times shorter most developed notosetae, their width varies within the single sample from equal or even grater than most developed notosetae to unvisible under enlarging near 100x, while the length are the same. Branchiae on two groups seperete with distance equal to diameter of branchophore. !st pair of notopodiae very small, its setae only slightly longer paleal, last pair of notopodiae sometimes reduced. 14 AS with slightly developed rudimental notopodia, without neuropodial cirri. Up to 25 mm long. Tube muddy, without incrustations.
Three branchiae of each group are in transverse row and fused with theirs bases, the fourth is free and behind middle of the three. There is small nephridial papilla between inners and fourthes branchiae. Paleal setae very small, much shorter and slimmer even setae of 1st pair of notopodia, which however only slightly less next. All notopodiae with globular cirri. 12 AS, all without rudimental notopodiae, but with cirri at upper ungle, shorth and thick onto 2 anterior AS and long and slim onto the rest. Pigidium with two anal cirri and some short rounded papillae. Up to 50 mm long. Tube long, cylindrical, thin-walled, muddy, practicaly without incrustations, smooth, dense, very similar to Euchone papillosa, but more elastic.
Branchiae of each group are in almost one transverse row. There are small nephridial papillae medially to inner branchiae. Paleal setae small, only slightly shorter most developed notosetae, but much slimer. 15-17 AS, all without rudimental notopodiae. but with cirri onto all excepted 2 anterior AS. Pigidium with two anal cirri. Up to 15 mm long. Tube muddy, cylindrical, thin-walled, often with transversal foldes as in Glyphanostomum pallescens, but as half, instead whole ring.
Peristomium with large lower lip, similar to Lysippe labiata one. Palea very small or absent. 2 groups of branchiae, they do not parting. Notosetae of 1st pair of notopodia only slightly shorter others. 13 AS. Up to 25 mm long.
See Jirkov, 1986ó for details.
Paleae larger notosetae. Two outers branchiae are in one transversal row, two inners -one just behind other. Inner branchiae 1,5-2 times shorter and slimmer outers. Notopodia os 1st TS very small, hardly visible. There is usually transversal ridge before 4th pair of notopodia, the similar brims are in large speciemens before 5th and 6th pairs of notopodia. Once more brime (the best developed) connects 11th pair of notopodia (5th from behind). The last brim is glandular, marks with withish color, but sometimes well visible only after using of dye. 11th pair of notopodia slightly turned medially, its notosetae are with dentate tip instead smooth capillar as others. 13 AS. All without rudimental notopodia and cirri. Pigidium with short rounded papillae only. Up to 30 mm long. Tube muddy, smooth, thin-walled, anteriorly usually incrusted with flat shall fragments and stones (similar to tubes of Melinna elisabethae and Euchone analis). Remarks. 2. Syntypes of Ampharete arctica var. gagarae Uschakov, 1950 are quite typical Sosane gracilis.
3. Anobothrus gracilis sensu Uschakov, 1955, drawing at puc.138ä have absolutely different set of branchiae and so is not Sosane gracilis s.str.
Branchiae into 2 groups, sepereted with distance greater than diameter of branchophore. Notopodiae third from the last TS are not cylindrical as others, but flattened with inner angle turned into cirrus. 11 AS without rudimental notopodia or they only slightly developed. Pigidium with 2 thick shortcirri and numerous small rounded papillae. Up to 10 mm long.
Remark. Banse (1979) have re-investigated holotype. He wrote that modifying notopodium are at 3rd from the last TS (it is besides, clear from the original description), instead last as it was for uncertain reason mentioned by Day (1964); Hartman (1965b); Hartmann-Schroder (1971); Fauchald (1977).
There is only species in the Ocean: L. conchilega (Pallas, 1766)
By our opinion all finds of the species within the North Polar Basin belong in reality to P.bansei.
There is only species within the Ocean: A. gracilis (Grube, 186O)
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Buccal S has ventro-lateral collar on the anterior margin, the
next is ventro-lateral semicircle. The type of glands of ventral
surface are similar to 'striped' sensu Williams(1984): anterior
part up to 4th setiger dyed with methilgrune complete, farther
back unpigmented bonds appear along boundaries between S, they
enlarge caudally and behind ca.9th setiger dyed bands turn to
slim almost unpigmented strips connecting neuropodium. U-form
unpigmented glandular ridge embracing 3rd Notopodium can present
in large specimens, its anterior branch distinctly higher than
posterior. Branchial stem is short and thick (diameter near equal
to high), there is pair of pectinate lobes on its tip, spreads
forward in 2-3 times less than back; lobes join in lower part
before stem and quite separate behind it. Inner pair of branchial
pectinate lobes attached slightly beneath of outer, spreads only
back, is ca.twice slender and shorter posterior part of outer
pair. 18 TS. 1st pair
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of notopodia is near equal to following; neuropodia start from
6th thoracic setiger, 1st pair of neuropodia with curved geniculate
acicular uncini, others - with hooks with. Length up to 60 mm.
Tube wall is delicate, soft, mud-detritus.
Remark. This species we consider as Terebellides stroemi s.str. because it fully agrees with description of Williams(1984).
Buccal S has ventro-lateral collar on the anterior margin, the next is ventro-lateral semicircle. The type of glandular pattern of ventral surface are similar to 'solid' sensu Williams (1984): up to 11th setiger it's dyed with methilgrune complete, without unpigmented band along S margin. Ventral surface of 1st-4th setigers is white and isn't dyed with methilgrune (only 4th setiger isn't dyed into 'solid'). Ventral surface of 1st-4th setiger of fixed specimens (unpigmented with any dye) is almost whiter farther back it's the same as of another body's surface. Branchiae are similar to T. stroemi ones, but the difference in thickness and length of inner pair of branchial pectinate lobes and posterior part of outer is less, they can be even almost equal. 18 TS. 1st pair of notopodia is much less following, can find hardly or even is completely absent; neuropodia start from 6th thoracic setiger, 1st pair of neuropodia with curved geniculate acicular uncini, others - with hooks with. Types length from 5 to 45 mm, width up to 2 mm (species distinctly less than T. stroemi). Tube's wall is delicate, soft, mud-detritus.
Etymology. The species have named after Dr.S.J.Williams, research of which (Williams, 1984) allowed to find new species.
Material. Holotype from st.7 R/V"Alaid, cruise 30, 74°30' N, 28°00' E, depth 385-390 m, collected 07.04.80, deposed into Zoological museum of Moscow State University, n.Pl 791. 161 paratypes collected within the Barents and Norwegian seas, depth 92-450 m, bottom temperature -1.53°- 7.43°C (16 samples), deposed into Zoological museum of Moscow State University, n.Pl 792...808. One sample was sent to Dr.S.J.Williams.
Peristomium usually with eyespots. Lateral lappets absent. 2 pairs of cirriform branchiae, cirri attached directly to body surface, instead short stem as in Artacama proboscidea and Amphitrite cirrata. Ventral surface much glandular, wrinkled, but without separated ventral glandular shields. Notopodia from 2nd branchiferous S nearly throughout the body, neuropodia from 2nd SS, all single-row. Dorsal body surface very characteristic, unique among Polychaeta of the Ocean: it looks cellular due breaks in muscle layer right under cuticle; cells form rather regular rows, especially anteriorly. However, specimens with poor developed cells or even without this character at all often occur. Up to 200 mm long. Tube irregularly twisted, with hard chitinous base covered with rather big stones or shell fragments, similar to tube of Pista maculata, but particles larger.
Form of proboscis strongly depends on fixation, usually it more or less conical. Lateral lappets and ventral glandular shields absent. Three pairs pf cirriform branchiae, cirri attached to very low stem (common base). 17 TS, two-rows neuropodia from 8th SS up to the torax end. The species can be easily differed from other Terebellidae of the Ocean with presence of dorsal neuropodial cirri with pointed or rounded tip. Up to 80 mm long. Tube muddy.
Remark. A lot of authors (Zatsepin, 1948; Uschakov, 1955; Holthe, 1986 a,b ¿ others.) take Neoamphitrite Hessle, 1917 as a distinct genus, characterizing with branched branchiae, while Amphitrite s.str. characterizing with cirriform ones. But cirriform branchiae of a type species of the genus A.cirrata only looks like cirriform. Closer investigation shows that "cirriform" branchiae attached to a low stem and thus are rather branches with shortened stem. In a typical cirriform branchiae (Thelepus cincinnatus) branches attached to body surface. So we joined to another authors (Fauvel, 1927; Hartmann-Schroder, 1971), reckoned these genera as synonyms.
Eyes absent. There are big nephridial papilla onto 3rd S. Notosetae from 4th S near throughout the body. Neurosetae from 8th to 25th-30th in two rows. Ventral glandular shields up to 9th-11th SS. Tube muddy.
Eyes and lateral lappets absent. There is a pair of nephridial papillae onto 3rd S, slightly medially to 1st pair of notopodia. 11 TS. Dorsal surface of 2nd-6th and distance between anterior parapodia become narrower anteriorly. 15 TS. Anterior 11 S short with distinct ventral glandular shields, from 9th TS segments become near twice longer. Two-rows neuropodia from up to the torax end. Up to 90 mm long. Tube thin-walled (thickness is in 4 time less inner diameter), muddy.
Eyes absent. Three anterior S with lateral lappets. Upper margin of lappets of 1st S is distinctly ventrally than ones of 2nd S, while upper margin of lappets of 2nd S is somewhat ventrally than ones of 3rd S. There is a pair of nephridial papillae onto 3rd S, slightly medially to 1st pair of notopodia. 11 TS. Dorsal surface of 2nd-6th and distance between anterior parapodia become narrower anteriorly. Anterior 11 S short with distinct ventral glandular shields, from 9th TS segments become near twice longer. Two-rows neuropodia from up to the torax end and onto 4 anterior AS. Up to 90 mm long. Tube thin-walled (thickness is in several time less inner diameter), muddy.
Eyes absent. 17 TS. Neuropodia from 8th SS (rarely 7th), form 8th up to 17th two-rows. Up to 70 mm long. Tube straight, skinny, covered with sand, shell fragments, foraminiferae.
Eyes absent. Three anterior S with lateral lappets. Upper margin of lappets of 1st S is distinctly ventrally than ones of 2nd S, while upper margin of lappets of 2nd S is distinctly ventrally than ones of 3rd S. Nephridial papillae onto 3rd S absent. Notopodia from 4th S. 10 TS. Dorsal surface of 4 anterior S with transverse folds, the biggest fold is onto 3rd S, others much less, but distinct. Dorsal surface of anterior S doesn't become narrower anteriorly, and anterior parapodia are not turned medially as in Lanassa venusta. Thoracal S of near the same length. Two-rows neuropodia from 8th SS up to the torax end and onto 7 anterior AS. Notosetae broadly bilimbate, with smooth tip. Up to 70 mm long. Tube thick-walled (thickness is near equal to inner diameter), muddy.
Remark. Comparison of species' descriptions allows to divide them into 4 morphotypes (others mentions did not accompany with descriptions). 1. Malmgren (1865): two-rows neuropodia onto 8th-16th SS. Iceland, Finmarken, Spetsbergen : 45-420 m. 2. Pettibone (1954): two-rows neuropodia onto 8th-17th SS. Point-Barrow (40 m), Labrador (27-100 m). 3. Hessle (1917), Zatsepin (1948:153, but table. XXXVIII, 17, where Malmgren figure was copied), Uschakov (1955): two-rows neuropodia from 8th to 17th-20th SS. Alten (Norway), 74-148 m, circumpolar within Arctic, the Japan and Bering seas, 16-1500 m. 4. Hartman (1948), Wesenberg-Lund (1950): two-rows neuropodia only onto 6 anterior AS (i.e. onto 11th-17th SS). Alaska bay (38- 95 m), east from Iceland (848-887 m). Investigation of two-rows neuropodia set in material from Iceland to the Chuckchee sea doesn't show any variation of the character. All our specimens were of 2nd morphotype. The difference between 2nd and 1st (type) morphotypes perhaps can be explain with ugliness of Malmgren specimen: probably it lacks of neuropodium at one of the anterior AS (judging to figure at 1st), because a distance between neuropodia of the last TS and the first AS two times more than between anothers; in our specimens all distance are equal. A variation of amount of two-rows neuropodia in 3rd morphotype perhaps can be explain with presence of several species in investigated by these authors material. May be several species were into Hessle material only while others took his diagnosis. The last morphotype sharply differ from others with absence of two-rows neuropodia at TS, while onto AS they set as in morphotype 2nd. Such late start of two-rows neuropodia makes the morphotype 4th unique among all others Terebellinae, such unique that doubt appears: is the description correct? May be 4 morphotype is identical with 2.
Branchiae are distinctly dichotomously branched 1-4 times, anterior are larger posterior. Lateral lobes onto 2nd-4th S, small distinct to absent, usually of anterior S more developed. 13 (rarely 14-15) TS. Ventral glandular shields up to 9-10 SS. Neuropodium from 8th to 16th-19th SS (usually to 18th) two-rows. Up to 67 SS, 40 mm length. Tube muddy, thick-wall.
Remark. Paramphitrite tetrabranchia, according to original descriptions doesn't differ from investigated by me syntypes of Amphitrite birulai, probably these two species are synonyms.
Remark. Some authors (Hartman, 1959, Fauchald, 1977, Holthe, 1986 a,b) concern Axionice as a distinct genus, characterizing with absence of long stem of neurosetae of anterior TS, contrary to Pista, having such stems. However Safronova (1988) have shoved that the very character have individual, age depended and geographyc variation. It is obviously, that character having interspecific variation cannot be used for diagnostic of genera, and so this two species have to be taken as synonyms. According the opinion of Safronova (pers.comm.) Pista - combined genus with confused taxonomy. However till a revision will be finished there is no use, by my opinion, to divide it, because it will not lead to clearness, rather vice versa.
Eyes absent. Lateral lappets onto 1st S absent, onto 2nd large ventral, joined ventrally with wide fold, onto 3rd small lateral. Branchiae arborescent, onto 2nd S. 17 TS. Neuroseta into two rows up to the torax end. Neurosetae can have long well developed stem (absent or poor developed into juvenils). Up to 1,5 mm wide (Far Eastern - up to 5.Ä mm). Tube usually muddy, with numerous foraminiferae or sand grains.
Eyes absent. Lateral lappets onto 1st S large ventro-lateral,
joined ventrally and hide prostomium here, onto 2nd absent, onto
3rd huge hide 2nd S cover even part of 1st S. Branchiae dichotomous,
onto 2nd S. 17 TS. Neuroseta form 4th S, into two rows from 8th
SS up to 13th (rarely 14th) SS (i.e. last 2-3 TS with single-row
neuropodium). Neurosetae have slim but distinct stem. Up to 60
mm long. Tube very characteristic: flat, sandy, sinoidaly twisted.
[Literature cited not included. Please see original text]