Andaniotes corpulentus (Thomson 1882)

Andaniotes corpulentus.—Stebbing 1910a:575

NOMENCLATURE.—The only Australian specimens of this genus heretofore recorded, from off Wata Mooli in 54–59 fathoms, may belong with this new species, which is clearly distinct from the New Zealand A. corpulentus.

DIAGNOSIS (of female).—Head 1.3 times as long as pereonite 2; article 1 of primary flagellum less than half as long as peduncle of antenna 1; mandibles twice as long as broad; palp of maxilla 1 slender, just failing to reach end of outer plate, all spines apical; outer plate of maxilliped reaching about three-fourths along palp article 2, outer plate subcircular, very stout, article 2 of palp nearly 1.5 times as long as article 1, article 3 shorter than 1 and article 4 shorter than 3; coxa 1 with acute apical angle; coxa 4 with ventral margin distinct from posterior margin and extending for at least half of coxal breadth, posterior margin parallel to anterior, then sweeping dorsally to broad lobe followed by shallow sinus; hand of gnathopod 1 about 47 percent as broad as long, bearing large apical spine; weak palm of gnathopod 2 bearing 5 large falcatoserrate spines; article 2 of pereopod 3 linear, of pereopod 4 broadly expanded and ovatorectangular, of pereopod 5 broadly expanded and rectangular, with horizontal distal margin; article 4 of pereopods 3–5 decurrent, with long posterior lobe strongly exceeding apex of article 5 on pereopods 4–5, reaching more than halfway along article 5 of pereopod 3; coalesced urosomites 2–3 with weak dorsal keel anteriorly; outer ramus of uropod 3 uniarticulate.

DESCRIPTION.—Accessory flagellum 2-articulate, article 2 minute, articles 4–5 of peduncle on antenna 2 with lateral setulose ridge; pereopods 1–5 with apical notch on article 6 at base of dactyl and weak distal slit on dactyl; pereopod 2 with bundles of setae on articles 2 and 3 but setae absent on pereopod 1; coxa 4 locked under pellucid anterior lobes of coxa 5; pleonal epimera 2–3 with softly rounded weak posteroventral cusp, epimeron 1 rounded posteroventrally but from lateral body view appearing quadrate.

HOLOTYPE.—NMV, female, 7.3 mm.

TYPE-LOCALITY.—Port Phillip 30, area 58, Queenscliff Point, Lonsdale, 35–40 feet, 2 April 1959.

RELATIONSHIP.—The female of this species differs from the female of A. corpulentus (Thomson) (=A. abyssorum (Stebbing, 1888), in the shorter article 1 of the primary flagellum on antenna 1, the narrower and slightly shorter palp of maxilla 1, the shorter palp and broader outer plate of the maxilliped, the shortened article 1 of the maxillipedal palp, the more strongly distinct ventral and posterior margins of coxa 4, the much longer posterior lobes of article 4 on pereopods 4–5, the ventrally truncate article 2 of pereopod 5, the broader rami of the uropods, and the 1-articulate outer ramus of uropod 3.

The male of A. corpulentus, figured by Stebbing (1897), has more distinct ventral and posterior margins of coxa 4 than the female figured by Stebbing (1888), and the male uropod 3 has the rami extremely shortened, the inner more than the outer, and on uropod 1 the inner ramus is relatively much thinner than the thickened outer ramus.

The lobe on article 4 of pereopod 5 is shortened in the male of A. corpulentus, and the posterior margin of article 2 on pereopod 4 is weakly excavate.

Males of the Australian new species are not available for comparisons.

MATERIAL.—Four specimens from the type-locality.

DISTRIBUTION.—Port Phillip, Victoria.