NIWA Guide to Polychaeta | Shore polychaetes | Pick shore group | Pick shore family | Shell polychaetes |
Eunicidae | Family Eunicidae (eunicid)
Eunicida (Annelida: Polychaeta) |
||
About Family Eunicidae polychaetes in New Zealand. | ||||
How to recognise the family: | Eunicids are large, muscular carnivores or scavengers, occurring in crevice habitats of all kinds. The characteristic complex jaws consist of a pair of mandibles, blunt-ended plates often impregnated with calcium carbonate, ventral to a pair of large forcep-like maxillae plates, and another pair of toothed maxillae, an unpaired left maxilla, and three further maxillae pairs, all diminishing in size. Eunicids are readily recognised from their dorsal head structure of one to five short, similar, beaded 'antennae' in a line at the rear of the prostomium together with a pair of eyes. Eunicids may have a pair of dorsal peristomial cirri on the peristomium as in genera Eunice and Palola, and usually have comb-like branched gills on each mid-body segment except in Paramarphysa and Lysidice. The gills are outgrowths at the base of the dorsal cirrus. There are no notochaetae. The neurochaetae include heavy acicular toothed hooks, slender compound falcigers, and also capillaries plus a few fine chaetae with comb-like ends. Palola lacks subacicular hooks. The pygidium has two pairs of anal cirri, but the upper pair is always very short. Reproductive modes in eunicids are varied, but this is the family of the famous tropical Palolo worms (Palola) in which the posterior gamete-filled ends break free and, synchronised with the lunar cycle, swarm to the surface en masse to spawn. Adult size: Eunicids can be more than 500 mm long and of finger thickness, and most species are large worms at around 5-10 cm long. | |||
How to recognise the New Zealand genera: | Eunice, Marphysa, Palola and Paramarphysa have five antennae, whereas Lysidice has three. Marphysa lack a pair of peristomial cirri. Eunice itself is a large genus of over 200 species worldwide. About five of the species recorded for New Zealand remain valid after a recent review. | |||
Quick pick shore species: | Eunice australis Quatrefages, 1865 appears to be the commonest intertidal species. It has branched gills from chaetiger seven and pale aciculae and hooks. Eunice species look very similar to one another, at least in the preserved state. The live colour pattern may help, but many Eunice are dark red or brown with a white dorsal band on an anterior segment and white spots posteriorly. Marphysa depressa (Schmarda, 1861) is grey with red gills, with up to four gill filaments from mid-body onwards. | |||
Possible misidentifications: | None, though all Eunicida clade have similarities. | |||
Distributions, lifestyle, and habitat: | Throughout New Zealand in the intertidal, and subtidal to continental shelf depths. Amongst encrusting growths and in crevices, and rarely in soft sediments unless also under rocks. Marphysa depressa is common in muddy rock crevices. | |||
Abundance: | Common, but rarely highly abundant. | |||
Taxonomic note: | Unlike the co-occurring onuphids of similar size, each antenna does not have a long enlarged basal joint. Taxonomists now consider the outer pair of 'antennae' to be palps, with the broad bluntly-rounded 'palps' actually being the upper lips of the mouth. Subtidal Marphysa disjuncta Hartman, 1961 has gills over a short region of about chaetiger 14 to 30. Eunice aphroditois (Pallas, 1788) is a very large subtidal species with inflated dorsal cirri. It may be an ambush predator, and it has impressive jaws. New Zealand records may be of a related species. | |||
References: | (Augener 1924b: p399-412, f8-9), (Day & Hutchings 1979: p114-117), (Ehlers 1904: p30-33, P4.8-12), (Fauchald 1986: p241-262, f1-82), (Fauchald 1992: p1-28, 74, 288-291, 324-325, f17, 98, 110), (Knox 1951b: p65-69, f6-12), (Knox 1960a: p124-126, f187-198), (Knox & Cameron 1970: p80-81, f13-22), (Knox & Green 1972a: p459-470, f1-30), (Orensanz 1990: p133), (Schmarda 1861: p127-128). (Full citations at Family pages literature cited list.) |
|||
Species in the guide: | Rock Species: Marphysa depressa | |||
Sand Species: None for this family. | ||||
Shell Species: None for this family. | ||||
Internet sources: |
GOOGLE Search | AlltheWeb Search | CISTI | CBIF BiOSC Gateway | GOBASE Molecular | GenBank | | |||
Family in Ubio Taxonomic Name Server | PubMed | Scirus | Zoological Record | | ||||
Note: use the Back button of your browser to return to Shore Polychaete Guide. |
||||
The information provided by this page and by the pages of the "more information" links is held in a structured form for rapid and frequent updating and improvement. Descriptive text is compiled from a number of database fields, some of which may occasionally be empty. Last modified by G. Read, 25/07/2004 (dd/mm/yy) |