Dulichiella terminos, Published, 2007

Published, First, 2007, A revision of the tropical / temperate amphipod genus Dulichiella Stout, 1912, and the description of a new Atlantic genus Verdeia gen. nov. (Crustacea: Amphipoda: Melitidae), Zootaxa 1424, pp. 1-62 : 47-48

Dulichiella terminos sp. nov.

( Fig. 36)

Dulichiella appendiculata . – Ledoyer, 1986: 185, figs 8–9.

Type material. Holotype male, 6 mm, Estero Pargo, Laguna de Términos , Campeche Bay, Mexico, Gulf of Mexico, stn 17 (illustrated by Ledoyer, 1986, whereabouts of specimen not known, probably no longer extant).

Type locality. Estero Pargo, Laguna de Términos , Campeche Bay, Mexico , Gulf of Mexico.

Additional material. 1 female, Estero Pargo, Laguna de Términos , Campeche Bay, Mexico, Gulf of Mexico, stn 16 . 4 males, 2 females and 1 juvenile, same as type locality.

Description. Based on Ledoyer, 1986: 185, fig. 8. Body large. Head eyes round; lateral cephalic lobe broad, truncated, anteroventral corner rounded (no apparent seta). Antenna 1 peduncular article 1 shorter than article 2, with 3 robust setae along posterior margin. Antenna 2 peduncular article 2 cone gland reaching at least to end of peduncular article 3; article 4 subequal to article 5. Mandibular palp article 1 about as long as broad, inner margin article 1 not produced distally; article 2 subequal to article 3.

Gnathopod 1 coxa anteroventral corner not produced, anterior margin straight, posteroventral corner notch present; carpus longer than propodus; propodus small, linear, palm shape unknown, defined by posterodistal corner. Gnathopod 2 coxa posteroventral corner notch present; (larger) propodus distolateral crown with 3 acute distinct spines, palm sinusoidal, produced, posterodistal corner upturned, posterodistal corner with dactylus fitting into corner; dactylus apically hooked; (smaller) merus with rounded posteroventral corner; palm convex, with robust setae; dactylus with 1 or 2 setae on anterior margin. Pereopods 6–7 merus, carpus and propodus unknown. Pereopod 6 basis posterior margin straight; dactylar unguis anterior margin with accessory spine.

Pleonite/urosomite dorsal spine formula (9-9-9-5-6-2). Pleonites 1–3 with sparse dorsal setae. Epimeron 3 posteroventral margin smooth. Urosomite 1 with spine at midline, no conspicuous medial gape. Urosomite 2 with two groups of 1–3 small dorsolateral robust setae. Urosomite 3 without dorsal setae; with 2 dorsal spines. Uropod 3 outer ramus very long, much longer than peduncle. Telson with dorsal robust setae.

Etymology. Named for the type locality, Laguna de Términos.

Habitat. Marine epibenthic, Thalassia beds in less than 10 m depth.

Remarks. Unfortunately no specimens of this species could be located. In accordance with ICZN Articles 72.5.6 and 73.1.4, we have designated the male illustrated by Ledoyer (1986) as the holotype. We have enquired in the Muséum National d'Histoire Naturelle, Paris, in the Museo Civico di Storia Naturale, Verona and the Station Marine D’endoume Marseille, the places where the majority of Ledoyer’s collections are housed and the material is not there. Dulichiella terminos is not as well known as other species and the specimens on which the species is based are lost. The female is not described. The mouthparts are not known except the mandible and the pereopods are unknown except the basis of pereopod 6. Nonetheless the acute spines on the distolateral crown of the large male gnathopod 2 distinguish D. terminos from all other species in the genus. Apparently the anteroventral margin of the head in D. terminos has no slender setae. If this is true then it is another autapomorphy defining the species.

Dulichiella terminos shares a very similar pleosome/urosome spine formula (9-9-9-5-4/6-2) with the eastern Pacific and southern Atlantic species, D. anisochir , D. guinea and D. spinosa .

Distribution. Mexico. Laguna de Términos, Campeche Bay, Mexico, Gulf of Mexico ( Ledoyer, 1986).