Epimeria (Laevepimeria) d’Acoz & Verheye 2017
- Dataset
- Epimeria of the Southern Ocean with notes on their relatives (Crustacea, Amphipoda, Eusiroidea)
- Rank
- SUBGENUS
Classification
- kingdom
- Animalia
- phylum
- Arthropoda
- class
- Malacostraca
- order
- Amphipoda
- family
- Epimeriidae
- genus
- Epimeria
biology_ecology
Ecology Benthic, 170 – 889 m.
description
Description Body opaque, with teguments moderately calcified. Rostrum small but not minute (reaching about mid of article 1 of antenna 1). Eyes not conical. Pereionites and pleonites completely smooth (only pleonite 3 can be posterodorsally produced into a low bump). Coxae 1 – 4 with sharp or blunt tip. Coxae 1 – 3 not keeled along their axis. Coxa 1 with anterior margin proximally concave and with subdistal dilatation. Coxa 4 without carina or groove; posteroventral border straight or nearly so. Coxae 5 – 6 toothless. Mid of posterior border of epimeral plates 1 – 3 not produced into a tooth. Posteroventral tooth of epimeral plate 3 small. Dorsal process of urosomite 1 produced into a large blunt tooth, of which the anterior border is shorter than the posterior border (the posterior border of the tooth extend to the posterior border of urosomite 1). Urosomite 2 without pair of small teeth pointing upwards. Lateral borders of urosomite 3 posteriorly terminated into a blunt angle. Peduncle of antenna 1 without teeth. Mandible with molar process drawn out, without triturative surface. Lower lip with wide hypopharyngeal gap. Palp of maxilliped with 4 articles. Gnathopods of normal size, with carpus and propodus very stout, with palm reduced or normal; propodus not expanded distally; dactylus very stout, with long slender posterior teeth perpendicular (or nearly perpendicular) to axis of dactylus (as in a comb). Basis of pereiopods 5 – 6 fairly broad, with indistinct trace of posteroproximal process, with or without trace posterodistal blunt process projecting posteriorly. Basis of pereiopod 7 with posterior border convex along all its length or with slight distal concavity, with large distal lobe reaching 0.3 of merus. Merus of pereiopod 7 broad. In pereiopod 7, the sum of the merus, carpus and propodus is short: only about as long as basis or a little bit more. Dactylus of pereiopods 5 – 7 short. Body length The maximum body length recorded in Laevepimeria species ranges between 15 and 32 mm.
description
urn: lsid: zoobank. org: act: D 1 B 62023 - FFE 4 - 4 AEB-A 345 - 89459 C 1063 AC
discussion
Remarks Laevepimeria subgen. nov. and Epimeriella form a large clade together. These subgenera share synapomorphies in the morphology of the mandible (molar process non triturative) and the lower lip (wide hypopharyngeal gap), and were formerly grouped into the genus Epimeriella s. lat. However, Laevepimeria subgen. nov. and Epimeriella s. str. exhibit striking differences in the morphology of the body, gnathopods and pereiopods. These differences are presumably related to their benthic lifestyle (Laevepimeria subgen. nov.) versus a pelagic or semi-pelagic lifestyle (Epimeriella). These subgenera can be identified without dissection, which was not possible with the former concept of Epimeriella.
distribution
Distribution Circum-Antarctic, as far north as Elephant Island.
etymology
Etymology Combination of laevis, smooth in Latin, and Epimeria. That name, which is feminine, alludes to the absence of ornamentation in the species of that subgenus.
type_taxon
Type species Epimeria walkeri (K. H. Barnard, 1930).