Schizocuma bacescui, 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 : 43

Schizocuma bacescui sp. nov.

Fig. 48

Holotype subadult ♂, 4.4 mm, P.90699, Australia, NSW, northeast of Eden , -37.003° 150.335°, 250–300 m, Waren dredge, shelly bryozoan sand, 11 Dec 1986, P.A. Hutchings, W.F. Ponder, R. T. Springthorpe, RV Franklin, FR 1086-05, in AM . Paratypes: 7 subadult ♂♂, P.90700; 1 subadult ♂, P.65075.

Etymology. The species is dedicated to the memory of Dr Mihai Băcescu (1908–1999), one of the most famous specialists in Crustacea Peracarida, former director of the “Grigore Antipa” Museum (1964–1988), as a sign of eternal gratitude for all his generous advices he offered to his last pupil in Crustacea.

Diagnosis. Carapace 0.3 entire length, 6 pairs of sidespins dorsally; eyelobe without lenses; pereon with dorsal and lateral spines, pleon with dorsal and lateral spines on first 2 segments, only lateral spines on other 4 segments; antenna 1 accessory flagellum with 2 articles; maxilliped 3 merus with 1 tooth propodus, 1.4 merus length; pereopod 1 carpus 2nd longest article; pereopod 2 dactylus, 2.5 propodus length; uropodal peduncle 2 pleonite 6 length, 1.9 endopod length, seven setae medially; endopod 1.4 exopod length.

Description. Carapace 0.3 body length, 1.6 as long as high, 6 pairs of spines dorsally; ocular lobe without lenses; 1 pair of spines on frontal lobe; serrate pseudorostral lobe, pseudorostral lobe 0.3 carapace length; antennal notch well marked; serrate anterolateral margin 1 tooth on anterolateral corner; several long simple setae Fig. 48 A, B ). — Pereonites with dorsal and lateral spines. — Pleonites 1 and 2 with dorsal and lateral spines, only lateral on other 4 segments. — Antenna 1 peduncle article 1 as long as rest of articles, with 1 tooth medially; article 2 as long as article 3, with 1 tubercle; main flagellum, with 3 articles, 1.16 article 3 length; accessory flagellum, with 2 articles, 0.9 main flagellum article 1; aesthetascs 2 main flagellum length ( Fig. 48 C, D ). — Maxilliped 3 basis 0.8 rest of article’s length, with process, 1 simple and 2 plumose setae; merus 3 ischium length, with 1 tooth and 4 plumose setae; carpus 0.8 merus length, with 3 plumose seta; propodus 1.7 carpus length, with 1 simple and 2 pappose setae; dactylus 0.5 propodus length, with 4 simple setae; with exopod ( Fig. 48 E ). — Pereopod 1 basis 0.6 of entire length; merus 2 ischium length, with 1 simple seta; carpus 2 merus length, with 2 simple setae; propodus 0.8 carpus length, with 4 simple setae; dactylus 0.5 propodus length, with 5 simple setae; with exopod ( Fig. 48 F ). — Pereopod 2 basis 0.3 rest of article’s length; merus 4.3 ischium length, with 1 simple seta; carpus 1.7 merus length, with 2 simple setae; dactylus, 2.5 propodus length, with 8 simple setae; with exopod ( Fig. 48 G ). — Pereopods 3–5 with decreasing basis and increasing carpus; with simple and annulate setae; dactylus with 1 long simple terminal seta; pereopods 3, 4 with exopods ( Fig. 48 H-J). — Uropod peduncle 2 pleonite 6 length, 1.9 endopod length, seven simple setae medially; endopod 1.4 exopod length, exopod terminal seta, broken, endopod with serrate margin medially and 7 simple setae ( Fig. 48 K ).

Remarks. Schizocuma bacescui sp. nov. is similar to S. spinosum ( Jones, 1984) from the southwest Atlantic, with numerous dorsal spines. It differs with: carapace with fewer spines, six pairs of spines vs. seven pairs in S. spinosum , without mid-dorsal carina, shorter peduncle of uropod than in S. spinosum .

Distribution. Australia: SA—Kangaroo Island, at 6 m; and NSW—northeast of Eden, at 250–300 m depth.

Figures

Figure 48. Schizocuma bacescui sp. nov. Holotype male (A) body, lateral view; (B) body, dorsal view; (C) antenna 1; (D) antenna 1, detail; (E) maxilliped 3; (F) pereopod 1; (G) pereopod 2; (H) pereopod 3; (I) pereopod 4; (J) pereopod 5; (K) uropod. Scales: A 1 mm; B 1 mm; C, F–K 0.3 mm; D 0.1 mm; E 0.3 mm.