Nannastacus craciuni, Petrescu, Iorgu, Chatterjee, Tapas & Schizas, Nikolaos V., 2014

Petrescu, Iorgu, Chatterjee, Tapas & Schizas, Nikolaos V., 2014, Three new Nannastacidae (Crustacea: Cumacea) species from a Caribbean mesophotic ecosystem, Zootaxa 3765 (4), pp. 360-370 : 367-369

Nannastacus craciuni sp. nov.

( Fig. 4 )

Material examined. Holotype: immature female ( MGAB CUM 1689), Caribbean Sea, SE Mona Island (18°02'46.0800" N, 67°52'42.7200" W), Puerto Rico, wash from coral Agaricia lamarcki , 240 ft (73.1 meters) depth, 13.01.2010. Collected by the DMS-UPRM-CCRI Trimix Rebreather diving team.

Diagnosis. Body covered with highly granulated tegument, basis of maxilliped 3 without outer process, protuberace 0.54 times as long as carapace on each side, placed on a plateau visible only in dorsal view, uropodal peduncle 0.6 times of last pleonite length, half of endopod length.

Descripti on. Body ( Fig. 4 A), size: 1.27 mm.

Carapace ( Fig. 4 A, B). It’s 0.44 times of total body length, 1.62 times longer than high, covered with high granulated integument, posterior protuberance 0.54 times of carapace length on each side, placed on a plateau visible only in dorsal view ( Fig. 3 B), short upturned pseudorostrum, 0.4 times as long as ocular lobe, no space between each side, two groups of three lenses each, large antennal notch, anterior-ventral margin shortly serrate.

Antenna 1 ( Fig. 4 C). Basal article of peduncle 1.33 times as rest of articles combined, 2nd article with an outer process, short main flagellum with short aesthetascs, accessory flagellum with long pedunculate setae.

Maxilliped 3 ( Fig. 4 D). Basis 0.43 times as long as rest of articles combined together, 1 plumose seta on medial margin, 2 much longer setae on outer margin, merus 3 times of ischium length, 1 plumose seta on outer margin, carpus 0.94 times as long as merus, propodus 0.94 times as long as carpus, dactylus 0.58 times as long as propodus, terminal robust seta little shorter than dactylus, with slender exopod.

Pereopod 1 ( Fig. 4 E). Basis 0.53 times as long as rest of articles combined together, merus 1.25 times as long as ischium, carpus 1.93 times as long as merus, 1 simple seta on medial margin, propodus 0.88 times as long as carpus, 1 simple seta on each margin, dactylus 0.6 times as long as propodus, terminal robust seta much longer than dactylus, with slender exopod.

Pereopod 2 ( Fig. 4 F). Basis 0.57 times as long as rest of articles combined length, merus twice as long as ischium, 1 simple seta on medial margin, carpus 1.2 times as long as merus, 2 simple setae on medio-distal corner, dactylus 2.5 times as long as propodus, 9 setules and 1 simple seta on medial margin, 2 subterminal setae and one terminal robust seta 1.1 times dactylus length, with slender exopod.

Pereopod 3 ( Fig. 4 G). Basis 0.3 times as long as rest of articles combined together, short simple seta on medial margin, merus 1.3 times as long as ischium, short simple seta on medial margin, carpus 2.87 times as long as merus, short simple seta on medial margin, propodus 0.86 times of carpus length, dactylus about half of propodus fused with its terminal robust seta.

Pereopod 4 ( Fig. 4 H). Basis 0.27 times as long as rest of articles combined together, 1 short simple seta on medial margin, 1 simple seta on medial margin, merus 1.25 times as long as ischium, 1 simple seta on medial margin, carpus 2.5 times as long as merus, 1 simple seta on medial margin, propodus 0.8 times as long as carpus, dactylus fused with its terminal robust seta.

Pereopod 5 ( Fig. 4 I). Basis 0.25 times as long as rest of articles combined length, 1 simple seta on medial margin, merus 1.1 times as long as ischium, 1 simple seta on medial margin, carpus 2.27 times as long as merus, propodus 0.77 times as long as carpus, dactylus fused with its terminal robust seta.

Uropod ( Fig. 4 J). Peduncle 0.6 times last pleonite length, half of endopod length, serrate medial margin, exopod 0.53 times as long as endopod, terminal robust seta 1.25 times of exopod length, endopod with microserrate margins, 2 simple setae on medial margin, terminal robust seta 0.53 times of endopod length.

Etymology. The species is dedicated in honour of Dr. Nicolae Crăciun, lecturer at the Faculty of Biology from Bucharest, Romania, as a sign of deep thanks for his kind and discreet help.

Remarks. Nannastacus craciuni sp. nov. is closely related to N. atlanticus ( Băcescu & Muradian, 1972) from Eastern Atlantic African coast ( Băcescu & Muradian, 1972, Corbera & Sorbe, 1999). Both species have body covered with granulated or spiny tegument. Nannastacus craciuni sp. nov. mainly differs by the following characters: carapace with posterior protuberance 0.54 times carapace length on each side, placed on a plateau visible only in dorsal view, basis of maxilliped 3 without outer process, shorter uropodal endopod (endopod/ peduncle: 2 versus 2.43). This is the first report of the genus Nannastacus from the Western Atlantic, Caribbean Sea.

Figures

FIGURE 3. Cumella victoriae sp. nov. Holotype immature female A, body, latateral view; B, antennule; C, maxilliped 3; D, pereopod 1; E, pereopod 2; F, pereopod 3; G, pereopod 4; H, pereopod 5; I, left uropod. Scales (In mm): A, 0.1; B, 0.1; C, 0.05; D – H, 0.1; I, 0.05.

FIGURE 4. Nannastacus craciuni sp. nov. Holotype immature female A, body, latateral view; B, body, dorsal view; C, antennule; D, maxilliped 3; E, pereopod 1; F, pereopod 2; G, pereopod 3; H, pereopod 4; I, pereopod 5; J, left uropod. Scales (In mm): A, B, 0.5; C, 0.05; D – J, 0.2.