Anonyx Krøyer, 1838a

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 : 10

Anonyx Krøyer, 1838a

( Fig. 2 )

Anonyx Krøyer, 1838a: 256 .— Krøyer, 1838b: 243.— Stebbing, 1906: 53.— Gurjanova, 1962: 207 (key).— Steele & Brunel, 1968: 949 (key).—J.L. Barnard, 1969: 324.— Lincoln, 1979: 76.— Barnard & Karaman, 1991: 442 (key), 463.

Chironesimus Sars, 1891: 108 (type species, Anonyx debruynii Hoek, 1882 , monotypy).

Lakota Holmes, 1908: 498 (type species, Lakota carinata Holmes, 1908 , original designation).

Type species. Lysianassa lagena Krøyer, 1838b , selected by Boeck, 1876 (junior synonym of A. nugax ( Phipps, 1774)) .

Included species. Anonyx includes 50 species: A. abei Takekawa & Ishimaru, 2001 ; A. adoxus Hurley, 1963 ; A. affinis Ohlin, 1895 ; A. attenuatus Steele, 1989 ; A. barrowensis Steele, 1982 ; A. beringi Steele, 1982 ; A. birulai Gurjanova, 1962 ; A. bispinosus Steele, 1967 ; A. comecrudus J.L. Barnard, 1971 ; A. compactus Gurjanova, 1962 ; A. dalli Steele, 1983 ; A. debruynii Hoek, 1882 ; A. eous Gurjanova, 1962 ; A. eousides Steele, 1991 ; A. epistomicus Kudrjaschov, 1965 ; A. grebnitzkii Steele, 1991 ; A. gurjanovai Steele, 1986 ; A. hayashii Sekiguchi & Yamaguchi, 1983 ; A. hurleyi Steele, 1986 ; A. knipowitschi Gurjanova, 1962 ; A. laticoxae Gurjanova, 1962 ; A. lilljeborgi Boeck, 1871 ; A. makarovi Gurjanova,1962 ; A. minimus Gurjanova, 1962 ; A. multiarticulatus ( Pearse, 1913) ; A. nugax ( Phipps, 1774) ; A. ochoticus Gurjanova, 1962 ; A. oculatus Gurjanova, 1962 ; A. omorii Takekawa & Ishimaru, 2001 ; A. orientalis Gurjanova, 1962 ; A. pacificus Gurjanova, 1962 ; A. pareous Steele, 1991 ; A. pavlovskii Gurjanova, 1962 ; A. petersoni Steele, 1986 ; A. pseudeous Steele, 1991 ; A. robustus Gurjanova, 1962 ; A. sarsi Steele & Brunel, 1968 ; A. schefferi Steele, 1986 ; A. schokalsii Gurjanova, 1962 ; A. sculptifer Gurjanova, 1962 ; A. shoemakeri Steele, 1983 ; A. simplex Hirayama, 1985 ; A. stappersi Steele, 1989 ; A. stebbingi Steele, 1989 ; A. stegnegeri Steele, 1986 ; A. validus Gurjanova, 1962 ; A. volkovi Kudrjaschov, 1965 .

Incertae sedis. Anonyx anivae Gurjanova, 1962 (gnathopod 1 propodus margins subparallel, antenna 2 without brush setae, mouthparts unknown); A. derjugini Gurjanova, 1962 (accessory flagellum not forming a cap); Anonyx lebedi Gurjanova, 1962 (gnathopod 1 ischium long); Anonyx magnus Gurjanova, 1962 (gnathopod 1 very weakly subchelate and no constriction on uropod 2 inner ramus).

Removals. Anonyx lebedi Gurjanova, 1962 to Tmetonyx . Gnathopod 1 with long ischium and propodus with subparallel margins.

Diagnostic description. Antenna 1 peduncle article 1 without anterodistal lobe; accessory flagellum forming cap covering callynophore. Antenna 2 with brush setae. Mandible molar setose with vestigial triturating surface. Maxilla 1 outer plate a well developed 7/4 crown. Maxilla 2 inner plate slightly to significantly shorter than outer plate. Gnathopod 1 subchelate (occasionally parachelate); coxa 1 large, about as long as coxa 2, subrectangular with straight or concave anterior margin; ischium short (length less than 2 × breadth); carpus short (length 1 to 2 × breadth) or long; propodus margins slightly tapering distally. Uropod 2 inner ramus constricted (weak to strong). Telson moderately to deeply cleft.

Remarks. Anonyx appears to be most similar to Onisimus . Both genera have a subchelate first gnathopod with a short carpus. However Anonyx has bush setae on antenna 2 (absent in Onisimus ) and the molar is a strong setose tongue (a reduced column with triturating surface in Onisimus ). Both genera are scavengers with wide-spread distributions in arctic/boreal regions.

Anonyx is also similar to Tmetonyx . They differ in the accessory flagellum cap (absent in Tmetonyx ), the mandibular molar (setose with a reduced column with convex triturating surface in Tmetonyx ), the ischium of gnathopod 1 (long in Tmetonyx ), and the margins of the propodus (subparallel in Tmetonyx ).

Figures

FIGURE 2. Anonyx nugax (Phipps, 1774), female, 44.0 mm, ZMUC and habitus, male, 45.0 mm, ZMUC, from the Norwegian Sea; male A2 and U3, 46.0 mm, AM P.32406, from Igloolik, Nunaavut, Canada. Scale bars: gnathopods, pereopods, 2.0 mm; remainder, 1.0 mm.