Styloptocuma halei, Petrescu, 2018

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

Styloptocuma halei sp. nov.

Fig. 57

Holotype ♂, 3.22 mm, P.90704, Australia, NSW, east of Broken Bay , -33.67° 152.1°, 1108–1115 m, trawl, 19 Dec 1985, FRV Kapala , K85-21-05, in AM.

Etymology. The species is dedicated to the memory of Herbert Mathew Hale (1895–1963), former director of South Australian Museum (1928–1960), one of the most important specialists in Cumacea of all time. He described most of Cumacean taxa known from Australian waters.

Diagnosis. Carapace 0.24 body length, 2 mid-dorsal denticles, transverse serrate rows on pereonites 2 to 4, all pleonites with dorsal and ventral serration, 2 lateral serrate rows on first 5 segments; maxilliped 3 propodus 2nd longest article, as long as ischium to carpus together; pereopod 1 propodus 2nd longest article, 1.2 carpus length, 2.7 dactylus length; uropodal peduncle 2.7 pleonite 6 length.

Description. Carapace 0.24 body length, 3.4 as long as high, upturned pseudorostrum, 0.4 carapace length; 2 mid-dorsal denticles; very large antennal notch; serrate anterolateral margin ( Fig. 57 A ). Transverse serrate rows on pereonites 2 to 4. All pleonites with dorsal and ventral serration, 2 lateral serrate rows on pleonites 1-5. — Antenna 1 peduncle article 1 1.7 rest article’s length, with 2 simple setae; article 2 with robust process with 2 pedunculate setae; main flagellum 2 article 3 length, with 3 articles; accessory flagellum with 1 article; aesthetascs 1.2 main flagellum length ( Fig. 57 B ). — Maxilliped 3 basis 0.5 rest of article’s length, with 3 plumose setae; merus 2 ischium length, with 1 plumose seta; carpus as long as merus, with 1 plumose seta; propodus 2 carpus length, with 2 pappose setae; dactylus 0.5 propodus length, with 2 simple setae; with exopod ( Fig. 57 C ). — Pereopod 1 basis 0.4 rest of article’s length; merus 2.5 ischium length, with 1 simple seta; carpus 2.5 merus length, with 4 simple setae; propodus 1.2 carpus length, with 3 simple setae; dactylus 0.4 propodus length, with 3 simple setae; with exopod ( Fig. 57 D ). — Pereopod 2 broken, carpus to dactylus are missing; with exopod ( Fig. 57 E ). — Pereopod 3 basis 0.5 rest of article’s length; merus 1.4 ischium length; carpus 2.5 merus length, with 1 simple seta; propodus 0.5 carpus length; dactylus fused with terminal seta; with exopod ( Fig. 57 F ). — Pereopod 4 basis 0.9 rest of article’s length; merus 1.25 ischium length; carpus 3 merus length; propodus 0.6 carpus length; dactylus fused with terminal seta; with exopod ( Fig. 57 G ). — Pereopod 5 incompletely developed, with only 4 articles; basis 1.5 rest of article’s length; article 4 with 2 terminal setae ( Fig. 57 H ). — Uropod peduncle 2.7 pleonite 6th length, with 5 setae medially, rami with broken tips ( Fig. 57 I ).

Remarks. Styloptocuma halei sp. nov. is similar to S. spinosum Petrescu, 2006 from Australian waters and several others from the Atlantic Ocean described by Băcescu & Muradian (1974) and by Jones (1984) with dorsal teeth on the carapace and remaining body, more like S. erecta (Jones) . It differs with: carapace having fewer dorsal teeth (two vs. five in S. erecta ) and two serrate lateral rows on pleon instead of one in S. erecta missing in S. spinosum ). The pereopod 2 aspect could aberrant, possibly being regenerated.

Distribution. Australia: NSW—east of Broken Bay, at 1108–1115 m depth.

Figures

Figure 57. Styloptocuma halei sp. nov.Holotype male (A) body, lateral view; (B) antenna 1; (C) maxilliped 3; (D) pereopod 1; (E) pereopod 2; (F) pereopod 3; (G) pereopod 4; (H) pereopod 5. Scales: A 0.3 mm; B 0.2 mm; C,H 0.2 mm; D–G 0.3 mm.