Uristes Dana, 1849

Lowry, J. K. & Kilgallen, N. M., 2014, A generic review of the lysianassoid family Uristidae and descriptions of new taxa from Australian waters (Crustacea, Amphipoda, Uristidae), Zootaxa 3867 (1), pp. 1-92 : 80-83

Uristes Dana, 1849

( Fig. 49 , 50 )

Uristes Dana, 1849: 136 .— Dana, 1852: 209.— Dana, 1853: 917.— Bate, 1862: 89.— Stebbing, 1906: 63.— Stephensen, 1929: 64.—J.L. Barnard, 1962: 35.— Hurley, 1963: 91.—J.L. Barnard, 1969: 367.— Ledoyer, 1986: 816.— Barnard & Karaman, 1991: 538.— Lowry & Stoddart, 2003: 284 (catalogue).

Uristoides Schellenberg, 1931: 27 .— Barnard & Karaman, 1991: 539 (in part).

Type species. Uristes gigas Dana, 1852 , monotypy.

Included species. Uristes contains 2 species: U. gigas Dana, 1849 ; U. subchelatus ( Schellenberg, 1931) .

Incertae sedis. Uristes abyssi ( Norman, 1900) (family unknown); U. albinus (K.H. Barnard, 1932) (family unknown); U. dawsoni Hurley, 1963 (family unknown); U. entalladurus J.L. Barnard, 1963 ( Lysianassidae , Tryphosinae ); U. georgianus ( Schellenberg, 1931) (family unknown); U. natalensis K.H. Barnard, 1916 (family unknown); U. paramoi ( Schellenberg, 1931) .

Removals. Uristes perspinis J.L. Barnard, 1967 to the tryphosine genus Cedrosella Barnard & Karaman, 1987 based on gnathopod 1 with a tapering first coxa and a short carpus, a non-constricted inner ramus on uropod 2 and a moderately cleft telson.

Uristes abyssalis ( Stephensen, 1925) is tentatively removed to the tryphosine genus Gronella Barnard & Karaman, 1991 , based on mandible molar triturating, gnathopod 1 coxa is slightly tapering, carpus short, propodus margins subparallel and the telson moderately cleft . The condition of the male antenna 2 peduncle (with or without brush setae) and the condition of the inner ramus of uropod 2 (constricted or not) needs to be verified to confirm the generic placement.

Uristes barbatipes ( Stebbing, 1888) is removed the tryphosine genus Tasmanosa Lowry & Kilgallen, 2014 based on the well-developed antenna 1 accessory flagellum and the triturating molar, maxilla 2 inner plate slightly shorter than outer, the distinctive carpus and propodus of gnathopod 1.

Uristes serratus Schellenberg, 1931 and U. yamana Chiesa & Alonso de Pina, 2007 appear to be congeneric, and belong to a yet to be described genus in the Uristidae based on the absence of a callynophore in the female and apparently in the male, the compressed carpus of gnathopod 1 and the cleft telson.

Uristes adarei ( Walker, 1903) ; U. antennibrevis J.L. Barnard, 1962 ; U. californicus Hurley, 1963 ; U. mediator J.L. Barnard, 1962 ; U. stebbingi ( Walker, 1903) ; U. sulcus Griffiths, 1974 are removed to the tryphosine genus Tryphosella Bonnier, 1893 based on the triturating molar, maxilla 1 with a 6/5 setal-tooth arrangement, the tapering coxa of gnathopod 1.

Uristes velia J.L. Barnard, 1961 is removed to the tryphosine genus Cheirimedon Stebbing, 1888 based on the maxilla 1 setal-tooth arrangement; gnathopod 1 carpus short and propodus margins subparallel; pereopod 4 with weak posteroventral lobe; and telson deeply cleft .

Diagnostic description. [based on type species] Antenna 1 peduncle article 1 without anterodistal lobe; accessory flagellum not forming cap covering callynophore or flagellum with an elongate article 1 (at least twice as long as article 2) partially covering callynophore. Antenna 2 without brush setae. Mandible molar ridge-like, narrow, setose with narrow distal triturating surface. Maxilla 1 outer plate a well developed 7/4 crown. Maxilla 2 inner plate slightly shorter than outer plate. Gnathopod 1 subchelate; coxa 1 large, about as long as coxa 2, subrectangular with straight anterior margin or distally subovate; ischium short (length less than 2 × breadth); carpus short (length 1 to 2 × breadth) to long (length 2 to 4 × breadth); propodus margins subparallel or slightly tapering. Uropod 2 inner ramus not constricted. Telson deeply cleft .

Remarks. As Chisea & Alonso (2007) point out Uristes is in need of revision. The diagnosis provided here is based on the type species. Of the 23 species currently assigned to Uristes , only two remain. Eight of these species are so poorly described that they cannot be placed.

Based on the subchelate first gnathopod with a large coxa with a straight anterior margin and a short carpus Uristes appears to be most similar to the Arctic/boreal genera Anonyx and Onisimus . It differs from both in having a ridge-like narrow setose molar with a distal triturating surface and in not having an accessory flagellum cap.

Distribution. Southern Ocean and southern Australian waters.

Figures

FIGURE 49. Uristes gigas Dana, 1849, male, 14.6 mm, AM P.38310; female, approx. 19 mm, BMNH 1889:5:15:6 (as Tryphosa antennipotens); from off Heard Island, Southern Ocean. Scale bars: MP, MX1, 0.1 mm; remainder, 0.5 mm.

FIGURE 50. Uristes subchelatus (Schellenberg, 1931), syntype female, 17.5 mm, ZMB 22726, from Bahia Inutil, Magellanic area. LM, EP3, whole G1, whole G2, P5, T after Schellenberg (1931). Scale bars: 0.5 mm.