Styloptocuma sp.

Petrescu, Iorgu, 2018, On the Family Nannastacidae (Crustacea, Cumacea) from the Australian Museum Collection, Records of the Australian Museum 70 (1), pp. 1-111 : 50-51

Styloptocuma sp.

Fig. 58

Material examined: 1 manca, 4.25 mm, P.90706, Australia, NSW, northeast of Coffs Harbour , -30.216° 153.487°, 400 m, baited trap, 9–10 Sep 1994, J.K. Lowry, K. Dempsey, SEAS Project, MV Carrie Ann, NSW-1014, in AM.

Diagnosis. Carapace 0.3 of entire length, integument of the whole body and appendages densely beset with small spines, pereonites 4 and 5 with long dorsal spines, pleonites with several dorsal spines; propodus of 3rd maxilliped 2nd longest article, 1.4 dactylus length; carpus and propodus of 1st pereopod, subequal; dactylus of 2nd pereopod as long as carpus and propodus together; uropod peduncle 1.9 pleonite 6 length, as long as endopod.

Description. Carapace 0.3 of entire length, 3 as long as high; long upturned pseudorostrum; no antennal notch; integument of the whole body and appendages densely beset with small spines, 2 dorsal rows of 3 longer spines each, median lateral row of 3 longer spines, other row close to posterolateral margin of 5 spines; anterolateral margin with long serration, other longer spines on posterior elevation ( Fig. 58 A, B ). — Pereonites 4 and 5 with long dorsal spines. — Pleonites also with several dorsal longer spines. — Antenna 1 peduncle article 1 2.25 rest of article’s length, highly serrated; article 2 1.3 article 3 length; main flagellum 0.5 article 3 length; accessory flagellum with 1 article; aesthetascs 4.8 main flagellum length ( Fig. 58 C ). — Maxilliped 3 basis 0.8 rest of article’s length, serrate medially, with 3 plumose setae; merus 2 ischium length, with 1 plumose seta; carpus 1.25 merus length, with 1 plumose seta; propodus 1.5 carpus length, with 2 pappose setae; dactylus 0.7 propodus length, with 4 simple setae; with exopod ( Fig. 58 D ). — Pereopod 1 basis 0.38 of entire length; merus 2.1 ischium length; carpus 1.7 merus length, as long as propodus; propodus with 1 simple seta; dactylus 0.4 propodus length, with 5 simple setae; with exopod ( Fig.58 E ). — Pereopod 2 densely beset with small spines, basis 0.7 rest of article’s length, with 6 robust long setae; merus 3.6 ischium length; carpus 3.3 merus length, with 2 simple setae; dactylus 4.7 propodus length, with 5 simple setae; with exopod ( Fig. 58 F ). — Pereopods 3, 4 with serrate basis to carpus, with decreasing basis and increasing carpus length; dactylus fused with terminal simple seta ( Fig. 58 G-H). — Pereopod 5 very short, with single article, incompletely developed ( Fig. 58A ). — Uropod peduncle 1.9 pleonite 6 length, as long as endopod, 5 longer robust setae interspersed with shorter setae medially, 3 lateral longitudinal rows, serrated margins; exopod 0.9 endopod length, with serrate margins and lateral longitudinal serrate row; endopod with serrate margins, 2 serrate longitudinal rows, 4 lateral and 6 setae medially, terminal robust seta, broken ( Fig. 58 I ).

Remarks. Styloptocuma sp. is related to another Australian species, S. anae sp. nov., also with a spiny integument, but with fewer stronger spines. Styloptocuma sp. is more closely related to an Atlantic species (Mauritanian coast), S. dumitrumurariui Petrescu, 2007 , both with long spines on the body and appendages densely beset with smaller ones. Much longer spines and setae are present on the Australian species, pereopod 1 with carpus and propodus subequal vs. longer propodus, pereopod 2 with shorter dactylus, pereopod 4 with shorter carpus, uropod with shorter peduncle, 1.9 pleonite 6 length vs. 6 longer in S. dumitrumurariui , with more serrate rows and longer setae on peduncle and rami.

Distribution. Australia: NSW—northeast of Coffs Harbour, at 400 m depth.

Figures

Figure 58. Styloptocuma sp. postmanca (A) body, lateral view; (B) carapace, dorsal view; (C) antenna 1; (D) maxilliped 3; (E) pereopod 1; (F) pereopod 2; (G) pereopod 3; (H) pereopod 4; (I) uropod. Scales: A,B 0.5 mm; C–I 0.3 mm.