Dulichiella spinosa Stout, 1912

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 : 43-47

Dulichiella spinosa Stout, 1912

( Figs 33–35)

Dulichiella spinosa Stout, 1912: 141 , figs 179–180. – Karaman & Barnard, 1979: 153. – Barnard & Barnard, 1983: 668. – Jarrett & Bousfield, 1996: 13 (unconfirmed).

Melita fresnelii . – Shoemaker, 1941: 187. – Hewatt, 1946: 202 (unconfirmed).

Melita appendiculata . –J.L. Barnard, 1969: 126 (unconfirmed).

Type material. Neotype adult male, 7.3 mm, LACMNH CR1990-360.1, off Pt Vicente , Palos Verdes Peninsula, California, USA, (33°44'38"N 118°25'05"W), red algae, otter trawl, 27 m, Don Cadien, 9 May 1990.

Type locality. Living on red algae off Palos Verdes , California in about 27 m depth .

Additional material. Female, 12.5 mm, LACMNH CR1990.360.2. 73 specimens, LACMNH CR 1990- 360.3. 5 males, 5 females, AM P69771, same locality .

Description. Based on neotype male, 7.3 mm, LACMNH CR1990-360.1 and female, 12.5 mm, LAC-

MNH CR1990.360.2. Body large. Head eyes round; lateral cephalic lobe broad, truncated, anteroventral corner with slender setae. Antenna 1 peduncular article 1 shorter than article 2, with 3 robust setae along posterior margin. Antenna 2 peduncular article 2 cone gland not reaching 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 produced distally; article 2 shorter than article 3.

Gnathopod 1 coxa anteroventral corner not produced, anterior margin straight, posteroventral corner notch present (minute); palm straight, defined by posterodistal corner, with posterodistal robust setae. Gnathopod 2 coxa posteroventral corner notch absent; (larger) propodus distolateral crown with 3 rounded indistinct spines, palm sinusoidal, posterodistal corner produced, bilobed, dactylus fitting against corner; dactylus apically blunt; (smaller) merus with sharp posteroventral spine; palm straight, without robust setae, posterodistal corner with robust setae; dactylus with more than 2 setae on anterior margin. Pereopod 5 dactylar unguis anterior margin with accessory spine. Pereopods 6–7 basis, merus, carpus and propodus without

bunches of long slender setae. Pereopod 6 basis posterior margin straight; dactylar unguis anterior margin with accessory spine. Pereopod 7 basis posterior margin convex.

Pleonite/urosomite dorsal spine formula (9-9-7-5-4-2). Pleonites 1–3 with sparse dorsal setae. Epimeron 1 posteroventral corner with small acute or subacute spine. Epimeron 2 posteroventral corner acute. 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, about 2 x peduncle. Telson with dorsal robust setae.

Female (sexually dimorphic characters). Gnathopod 2 subequal in size, similar to smaller gnathopod 2 of male; palm slightly sinusoidal; dactylus posterior margin crenulate. Pereopod 7 basis expanded, posterior margin convex and tapering distally.

Habitat. Marine epibenthic, living among kelp holdfasts and red algae, sublittoral to at least 30 m depth.

Remarks. Shoemaker (1941) indicated that the material used by Stout (1912) was lost. He obtained fresh collections from Laguna Beach, California and re-identified Stout’s (1912) amphipods, including D. spinosa , which he referred to as D. fresnelii . J.L. Barnard (1969: 3) clearly stated that “Stout’s types, in the defunct Laguna Marine Laboratory of Pomona College, have been lost”. Further enquiries to Joel Martin and George Davis at the Los Angeles County Museum of Natural History indicated that no type material of D. spinosa was lodged there. Fortunately we were able to obtain new material of D. spinosa collected by Don Cadien (Marine Biology Lab, Los Angeles County Sanitation Department) from off Palos Verdes, California, near the type locality.

Although Dulichiella spinosa is the type species of the genus it has always been obscure. The original description of Stout (1912) is inadequate and there has never been a redescription. Subsequent identifications of the species ( Shoemaker, 1941; J.L. Barnard, 1969; Jarrett & Bousfield, 1996) have been confused. J.L. Barnard (1969) reported new material, as M. appendiculata from Goleta, California, but with no evidence for the species identification. Jarrett & Bousfield (1996) indicated that they had seen material of D. spinosa from central “ California northwards”, but they give no detailed locality information and no evidence for their identification. Both records (J.L. Barnard, 1969; Jarrett & Bousfield, 1996) need confirmation.

For these reasons we have selected a neotype for the species. The redescription presented here, based on new material from near the original type locality, allows us to compare D. spinosa with other species in the genus.

Dulichiella spinosa has 9 dorsal spines each on the first two segment of the pleosome, in common with three Atlantic Ocean species: D. anisochir from Brazil, D. guinea from Guinea, and D. terminos from the Gulf of Mexico. Dulichiella spinosa is easily distinguished from D. terminos by the blunt spines on the distolateral crown of the large male gnathopod 2. Dulichiella spinosa is very similar to D. anisochir . Both have three blunt spines on the distolateral crown of the larger male gnathopod 2 and neither has well developed bunches of long setae on pereopods 6 and 7. Dulichiella spinosa differs from D. anisochir in the produced anteroventral corner of coxa 1 (not produced in D. anisochir ) and in the smooth posteroventral margin of epimeron 3 (minutely crenulate in D. anishochir ). Dulichiella spinosa differs from D. guinea in the shape of the palm of female gnathopod 2, straight in D. spinosa and excavate in D. guinea ; in the sparsely setose dorsal pleosome of D. spinosa and male pereopods 6–7 (all densely setose in D. guinea ).

Distribution. USA. California: Laguna Beach ( Stout, 1912); Palos Verdes; Goleta (J.L. Barnard, 1969).