Stegosoladidus simplex (K. H. Barnard, 1930 )

Berge, JØrgen, 2001, Revision of Stegosoladidus Barnard and Karaman, 1987 (Crustacea: Amphipoda: Stegocephalidae), redescription of two species and description of three new species, Journal of Natural History 35 (4), pp. 539-571 : 547-551

Stegosoladidus simplex (K. H. Barnard, 1930)

(®gures 9±11) Andaniotes simplex K. H. Barnard, 1930: 328 . Stegosoladidus simplex Barnard and Karaman, 1987: 869 . Stegosoladidus simplex Barnard and Karaman, 1991: 683 .

Material examined. Type material (NHM, London), four females, New Zealand, 183 m.

Distribution. New Zealand, Three Kings Island, 183 m. Only type material is known.

Description. Rostrum very small.

Antennae short. Antenna 1 accessory ¯agellum with two articles. Antenna 2 peduncle article 3 short, about as long as broad; article 4 longer than article 5.

Epistome produced laterally, rectangular, with a long ridge on each side; epistomal plate (medial keel) produced into a small elongate medial ridge covering the entire epistome.

Mandible incisor transverse, smooth, left lacinia mobilis present, reduced, laterally straight, conical.

Maxilla 1 palp uni-articulate, rectangular, apex not reaching above the apex of outer plate; outer plate distally rounded, ST in a pseudocrown, ST ®rst row with six setae (ST1±5, ST7), ST 1 ordinary (similar to ST 2±4), gap between ST 5 and ST 7, ST A present, located distally, part of ®rst row, ST B absent, ST C present; inner plate without a well developed shoulder, setae pappose.

Maxilla 2 ordinary, outer plate setae with no distal hooks or cleft; inner plate setae row A covering the entire margin, appressed to row B, row A setae pappose, three or four ®rst setae diOEerentiated from the other setae (weakly pappopectinate); row B setae proximally simple, distally with no cusps; row C absent; row D absent.

Maxilliped palp three-articulate, no articulation between article 1 and 2, article 2 distally unproduced, dactylus distally simple (pointed); inner plate without nodular setae; no medial setae row; distal setae row present, setae simple; inner setae row reduced to one or two setae, not conspicuously large; outer plate outer setae row present, marginal, setae attached normally, long robust, straight; no inner setae row; no distal setae-group.

Labrum very short; lobes symmetrical, both reduced.

Labium distally broad, oval.

Coxal plates and basis on the pereopods smooth. Coxae 1±3 contiguous.

Pereopod 1 coxal plate not as deep as basis, propodus subovate.

Pereopod 2 longer and thinner than pereopod 1, ischium elongate, ratio length 5 breadth exceeding 1.5, propodus subovate, palm absent.

Pereopod 4 coxa posteroventral lobe large, reaching about the base of pereon segment 7; basis anterior margin without long setae, posterior margin with long setae, plumose setae on distal anterior margin, no plumose setae on distal posterior margin, ischium with plumose setae on posterior distal margin.

Pereopod 6 basis posteriorly expanded, expansion conspicuous, rounded posteriorly, with no long plumose setae.

Pereopod 7 basis anterior margin straight, distally rounded, with medial row of setae, setae long, short and robust; carpus present, dactylus present.

Oostegites on pereopod 2±5, gills on pereopods 2±7.

Pleonite 1±3 dorsally smooth.

Urosomites 2 and 3 fused. Uropod 1 peduncle longer than rami. Uropod 2 peduncle longer than rami, outer ramus longer than inner. Uropod 3 peduncle at least as long as rami, outer ramus two-articulate, outer ramus longer than inner.

Telson about as long as broad, shorter than uropod 3 peduncle, cleft, apically rounded no submarginal setae on apex of each lobe.

Males: unknown.

Remarks. See S. complex . None of the four type specimens was in good enough condition to make drawings of the entire animal, however, its general appearance is very similar to that of its sister species S. complex .