Nematocarcinus tenuipes Spence-Bate 1888
- Dataset
- Nematocarcinus Milne Edwards, 1881 (Crustacea, Decapoda) from Southwestern Atlantic, including the Southern Mid-Atlantic Ridge area
- Rank
- SPECIES
Classification
- kingdom
- Animalia
- phylum
- Arthropoda
- class
- Malacostraca
- order
- Decapoda
- family
- Nematocarcinidae
- genus
- Nematocarcinus
- species
- Nematocarcinus tenuipes
description
Description. Body moderately slender; integument moderately hard, not membranous, surface smooth, shiny. Rostrum straight or slightly raised up; overreaching antennular peduncle with more than one third of its length (Fig. 8 A, C, E) or with less than one third of its length (Fig. 8 B, D); distance from rostrum apex to the rostrum distal dorsal tooth is similar than that between the remaining rostrum dorsal teeth (Figs. 8 A, B, E; 9 A, B) or wider than that (Fig. 8 C, D); rostrum dorsal margin (including postrostral crest) with 15 – 40 teeth (Figs. 8 A – E; 9 A, B), distance between teeth becoming wider distally; rostrum ventral margin unarmed (Fig. 8 B, E) or with one badly developed tooth (Fig. 8 C), or with one well developed tooth lying: between the apex and first dorsal tooth (Fig. 8 D), under the first dorsal tooth (Fig. 8 A), or after the first dorsal tooth (Fig. 9 A), in few cases two teeth can be present (Fig. 9 B). Eyes normally developed, its width noticeably larger than the diameter of the eye stalk. Posterodorsal margin of third abdominal somite somewhat developed, rounded. Continuation of its sides when crossing forms an obtuse angle of about 90 o or less (Fig. 9 C, D). Fifth abdominal somite pleura with its sides intersecting at an angle near 90 o, with distal tooth (Figs. 9 E, F; 10 A). Inner surface of the anterior margin of the pleura of the fifth abdominal somite with elongated, shallow but clearly noticeable ridge. Distoventral organ at sixth abdominal somite formed by two single parallel rows of long plumose setae, relatively widely spaced, extending to posterior margin of spots (Fig. 10 B); spots located at the sideways surface of sixth abdominal somite; spots length 2 – 3 times its width, distance between them is 2 – 3 times its width (Fig. 10 B). Telson with 8 pairs of dorsolateral spines; without accessory spine (Fig. 10 C, D).
discussion
Remarks. Comparing the southwestern Atlantic material with Burukovsky (2000 a; 2012; 2013) data, we observed that many features fit very well as rostrum dorsal teeth, third abdominal somite dorsal margin, fifth abdominal somite pleura, distoventral organ with a single pair of parallel rows of setae beginning at spots distal margin; some features present small differences as rostrum length, distoventral organ spots length and distance between spots; and only one feature show a high difference, the rostrum ventral teeth; we consider that all the observed variations are occurring at populations level (intra-specific variations) and they were included at species description.
distribution
Distribution. Nematocarcinus tenuipes presents a tropical-subtropical cosmopolitan distribution (Fig. 11). At Southeastern Atlantic it occurs at Gabon, Angola and Namibia coasts; and also at South Mid Atlantic ridge, from 2470 to 2840 m depth (Burukovsky 2007 a; 2012); Nematocarcinus tenuipes is recorded herein for the first time to the Southwestern Atlantic, from off Bahia to Rio de Janeiro states, Brazil, from 989 to 1931 m depth. At Indian and Pacific Oceans N. tenuipes occurs from the Agulhas Bank and Mozambique Strait up to Taiwan, Japan, New Caledonia, Hawaii, Vanuatu, Fiji and Tonga Islands at depths of 630 – 3075 m (usually 1400 – 1700 m) (Burukovsky 1991; 2000 a; 2002 c; 2012; 2013). In the Eastern Pacific this species is recorded at the East Pacific rise (12 ° 45 ' N / 103 ° 55 ' W, 2558 – 2619 m), and Chile continental slope (33 ° 42 ' S / 78 ° 18 ' W, 2520 m; 42 ° 43 ' S / 82 ° 11 ' W, 2570 m) (Burukovsky 2000 a; 2001 a; 2002 a; 2002 b; 2003; 2006 a; 2012; 2013).
materials_examined
Material examined. Oceanprof I: A – 1, 22 o 45´S / 40 o 10´W, 1322 m, 2 ovigerous females (22.58 – 24.11), MNRJ 19233; A – 6, 22 o 27´S / 39 o 52´W, 1649 m, 1 male (18.2), 1 female (20.6), 4 ovigerous females (21.8 – 27.8), MNRJ 19177; A – 8, 22 o 49´S / 40 o 16´W, 1305 m, 1 ovigerous female (23.2), MNRJ 19179; A – 12, 22 o 12´S / 39 o 47´W, 1640 m, 1 male (21.2), 1 ovigerous female (27.0), MNRJ 19176; A – 15, 21 o 50´S / 39 o 47´W, 1649 m, 3 ovigerous females (22.7 – 25.6), MNRJ 19178. Oceanprof II: A – 1, 22 o 41´S / 40 º 07´W, 1318 m, 4 females (17.0 – 21.7), MNRJ 19984; A – 9, 22 o 39´S / 40 o 01´W, 1605 m, 1 ovigerous female (22.2), MNRJ 19997; A – 17, 22 o 15´S / 39 o 51´W, 1332 m, 1 female (21.5), MNRJ 19998; A – 18, 22 o 15´S / 39 o 47´W, 1627 m, 1 ovigerous female (24.7), MNRJ 19960; Habitats. Hab 1, 23 o 51 ' S / 41 o 02 ' W, 1931 m, 1 male (20.4), 1 female (21.3), 2 ovigerous females (19.7, 23.4), MNRJ 21750; Hab 3, 22 o 54 ' S / 40 o 17 ' W, 1886 m, 4 males (16.1 – 21.6), 2 females (24.2, 25.6), 1 ovigerous female (23.0), MNRJ 21749; Hab 5, 22 o 20 ' S / 39 o 42 ' W, 1900 m, 3 males (18.6 – 20.4), 3 females (19.5 – 23.9), 6 ovigerous females (20.2 – 24.6), MNRJ 21748; Hab 6, 21 o 51 ' S / 39 o 41 ' W, 1912 m, 1 female (24.3), 3 ovigerous females (22.6 – 24.3), MNRJ 21745; Hab 7, 21 o 36 ' S / 39 o 35 ' W, 1889 m, 4 males (20.1 – 21.0), 3 females (21.4 – 22.9), 4 ovigerous females (21.5 – 23.6), MNRJ 21746; Hab 8, 21 o 7 ' S / 39 o 38 ' W, 1890 m, 6 males (16.2 – 21.4), 2 females (21.9, 23.0), 7 ovigerous females (20.8 – 25.5), MNRJ 21747; Hab 13, 21 o 40 ' S / 39 o 57 ' W, 989 m, 1 male (13.3), 1 female (13.4), MNRJ 21751. REVIZEE: E – 0520, 13 o 21 ’ S / 38 o 16 ’ W, 2137 m, 3 males (16.2 – 21.5), 1 female (21.8), MNRJ 14717; E – 0525, 20 o 08 ’ S / 38 o 38 ’ W, 1639 m, 1 male (carapace lost in part), MNRJ 14712; E – 0527, 19 o 50 ’ S / 39 o 10 ’ W, 1402 m, 1 ovigerous female (24.6), MNRJ 23454; E – 0551, 21 o 07´S / 39 o 49´W, 1642 m, 1 female (21.6), 3 ovigerous females (21.6 – 27.1), MNRJ 14698; E – 0552, 21 o 07 ’ S / 39 o 46 ’ W, 1694 m, 1 female (22.7), MNRJ 14703. MAR-ECO: Superstation 8, WR Local station 201, 30 o 00 ’ S / 02 o 49 ’ E, 1074 m, 2 males (8.2 – 22.9), 4 females (14.8 – 22.1), MNRJ 22585; Superstation 9, WR Local station 201, 32 o 50´S / 01 o 49´E, 1107 m, 5 females (11.2 – 23.7), 2 ovigerous females (17.4 – 29.0), MNRJ 22588; Superstation 4, SEMS Local station 201, 0 4 o 40
S / 12 o 16
W, 2014 m, 1 ovigerous female (19.0), MNRJ 22589; Superstation 7, WR Local station 201, 29 o 27´S / 0 1 o 08´E, 3721 m, 1 female (12.9), MNRJ 22590. Additional material: NMNH: 35 o 09N / 139 o 19
E, North Pacific, Japan, 1122 m, coll. Albatross, 4 females (13.3 – 17.0), id. Burukovsky, USNM 183440; North Pacific, Japan, 1057 m, coll. USFC, 1 ovigerous female (21.0); 32 o 34N / 132 o 21´E, id. Burukovsky, USNM 183537; 30 o 34
N / 129 o 19`E, North Pacific, Japan, 804 m, coll. USFC, 5 females (12.3 – 15.0), 1 ovigerous female (17.9), id. Burukovsky, USNM 183414.