Cumella hexadentata, Petrescu, Iorgu, Chatterjee, Tapas & Schizas, Nikolaos V., 2016

Petrescu, Iorgu, Chatterjee, Tapas & Schizas, Nikolaos V., 2016, New species and new records of Cumacea (Crustacea: Peracarida: Cumacea) from mesophotic reefs of Puerto Rico and U. S. Virgin Islands, Caribbean Sea, Zootaxa 4199 (1), pp. 1-78 : 24-26

Cumella hexadentata sp. nov.

( Fig. 9 )

Material examined. Holotype subadult female ( MGAB CUM 1804 ), St. John , U.S. Virgin Islands, Caribbean Sea, May 8, 2012, 18°13'18.6960"N, 64°40'33.4560"W, 54 m, collected during the 2012 UPRM-DMS Mesophotic cruise ; paratypes: 2 subadult females ( MGAB CUM 1781 ), El Seco, Vieques Island, Puerto Rico, Caribbean Sea, January 17, 2010, 70 m, 18°07'24.8520"N, 65°12'05.7600"W, collected during the 2010 UPRM-DMS Mesophotic cruise.

Diagnosis. Tuberculate integument, five long dorsal denticles and one shorter on dorsal margin of carapace, serrate anterior extremity of pseudorostral lobes, three teeth on anterior-ventral corner on carapace, ocular lobe with five lenses.

Description. Subadult female (holotype MGAB CUM 1804).

Body size: 1.53 mm ( Fig. 9 A).

Carapace ( Fig. 9 A, B). Tuberculate integument, 0.32 of total body length, 1.45 times as long as high, 1.74 times as long as wide, five long dorsal denticles and one shorter, from ocular lobe to posterior margin, serrate anterior extremity of pseudorostral lobes, three teeth on anterior-ventral corner, ocular lobe with five lenses, large antennal notch.

Pereion, 0.24 times total length.

Pleon, 0.48 times total length.

Antenna 1 ( Fig. 9 C). Basal article of peduncle longer than rest of peduncle, main flagellum shorter than apical article of peduncle, long aesthetascs, minute accessory flagellum.

Maxilliped 3 ( Fig. 9 D). Basis 0.4 times as long as rest of articles together, three short plumose setae on medial margin, two, much longer, pappose ones on outer margin; merus 0.35 times as long as ischium, one short plumose seta on medial margin, one long pappose seta on outer margin; carpus 0.71 times as long as merus, two short plumose setae on medial margin, one long plumose seta on outer margin; propodus 1.66 times as long as carpus, two pappose setae on medial margin; dactylus 0.6 times propodus length, one simple seta on medial margin, two on outer one, terminal robust seta shorter than dactylus length; small, incompletely developed exopod.

Pereopod 1 ( Fig. 9 E). Basis 0.45 times as long as rest of articles together, one simple seta on medial margin; merus 1.66 times as long as ischium, one simple seta on medial margin of ischium and merus; carpus 2.7 times as long as merus, three simple setae on medial margin; propodus 0.74 times as long as carpus, two setae on medial margin, one on outer margin; dactylus 0.5 times as long as propodus, robust terminal seta as long as dactylus; incompletely developed exopod.

Pereopod 2 ( Fig. 9 F). Basis 0.56 times rest of articles combined length; merus 3.33 times ischium length, one simple seta on outer margin; carpus as long as merus, two setae on both margins; dactylus 1.25 times as long as propodus, two setae on medial margin, three subterminal setae and one terminal robust seta 1.5 times dactylus length; incompletely developed exopod.

Pereopod 3 ( Fig. 9 G). Basis 0.83 times as long as rest of articles together; merus 1.11 times as long as ischium, one seta on outer margin, carpus 1.42 times as long as merus, one seta on outer margin; propodus 1.2 times as long as carpus, dactylus fused with terminal robust seta.

Pereopod 4 ( Fig. 9 H). Basis 0.52 times as long as rest of articles together; carpus 1.3 times as long as merus; propodus as long as carpus, one seta on outer margins of ischium to carpus; dactylus fused with terminal robust seta.

Pereopod 5 ( Fig. 9 I). Basis 0.35 times as long as rest of articles together; carpus 1.5 times as long as merus; propodus 1.16 times as long as carpus, one setule on medial margin; dactylus fused with terminal robust seta.

Uropod ( Fig. 9 J). Peduncle 0.9 times as long as last pleonite, one seta on medial margin, 1.12 times endopod length; exopod 0.72 times as long as endopod, terminal robust seta 1.11 times exopod length; endopod with two simple setae on medial margin, terminal robust seta 0.68 times endopod length.

Etymology. The species is named hexadentata after the Greek hexa, six, and from the Latin dentata, toothed, after the six dorsal denticles of the carapace.

Remarks. Cumella hexadentata sp. nov. resembles C. victoriae Petrescu, Chatterjee & Schizas, 2014 from Puerto Rico ( Petrescu et al., 2014b) in having six denticles on carapace and a short uropod. It differs in: 1) three denticles on anterior ventral corner in C. hexadentata vs. none in C. victoriae ; 2) ocular lobe with five lenses vs. two; 3) dorsal denticles on pereonites 1–3; 4) antenna 1 with compose pedunculate setae on 2nd and 3rd articles of peduncle vs. none; 5) maxilliped 3 with three setae on medial margin of basis, one on merus and two on carpus vs. only on basis; 6) pereopod 1 with setae on medial margin of basis to propodus vs. none; 7) uropodal peduncle with one seta on medial margin vs. none.

Figures

FIGURE 9. Cumella hexadentata sp. nov. Holotype subadult female. 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, pereopod 5; J, uropod. Scale bars: A, B, 0.5 mm; C – J, 0.1 mm.