Nematocarcinus altus Spence Bate 1888

Nematocarcinus altus Bate, 1888

Nematocarcinus altus Bate, 1888:809, pl. 132: fig. 4 [type-locality: eastern Celebes Sea; 2°55′N, 124°53′E; 3931 m].

DIAGNOSIS.—Rostrum slightly overreaching antennal scale, armed dorsally with 10 close-set teeth above and posterior to orbit and about 8 much more widely spaced teeth on rostrum proper, armed ventrally with 5 inconspicuous teeth; abdomen with 3rd somite noticeably produced posteromesially; telson short, not overreaching mesial branch of uropod; carapace length 35 mm.

RANGE.—Known only from the unique type-specimen from the Celebes Sea.

*33. Nematocarcinus bituberculatus, new species

DIAGNOSIS.—Rostrum curving slightly dorsad, reaching about to level of distal end of antennular peduncle, armed dorsally with 2–4 teeth posterior to orbit and 6 teeth becoming more widely spaced anteriorly on rostrum proper, ventral margin unarmed or with single subapical tooth; abdomen with 3rd somite rounded posteriorly, only moderately produced, pleuron of 5th somite armed with sharp posteroventral tooth, 6th somite with paired tubercles near posterior end of ventral midline; telson reaching about as far as distal end of lateral branch of uropod; maximum carapace length about 25 mm.

DESCRIPTION.—Rostrum (Figure 37a) curving slightly dorsad, reaching about to level of distal end of antennular peduncle; dorsal margin armed with 8–10 basally articulated, somewhat appressed teeth becoming more widely spaced anteriorly, 2–4 teeth of dorsal series situated on carapace posterior to level of orbital margin; ventral margin unarmed or with single small fixed tooth near apex. Carapace without prominent grooves or ridges except for rather broad groove on anterior extending posteriorly and slightly ventrad from orbital region. Antennal and pterygostomial spines well developed, sharp. Abdomen with pleura rounded on 4 anterior somites; 3rd somite (Figure 37b) rounded posteriorly, not much produced posteromesially, 5th somite (Figure 37c) with pleuron armed with sharp posteroventral tooth; 6th somite with paired tubercles near posterior end of ventral midline (Figure 37d); pre-anal tooth (Figure 37e) sharp, curved spine extending posteriorly from rather deep flange between bases of uropods. Telson (Figure 37f) reaching about as far as distal end of lateral branch of uropod, armed with 9 or 10 pairs of dorsolateral spinules and 2 pairs of posterior spines (Figure 37g), lateral pair more than twice as long as mesial pair.

Eyes about as broad as long.

Antennular peduncle with stylocerite reaching about as far as dorsodistal margin of first segment, deeply and rather sharply notched dorsally in lateral view.

Antennal scale (Figure 37h) nearly 3 times as long as wide, distomesial angle of scale reaching fully as far as distolateral spine.

Mouthparts as illustrated (Figures 37i–n). Incisor process of mandible armed with 7 teeth. Third maxilliped reaching almost as far as end of antennal scale, exopod nearly reaching distal of antepenultimate segment.

First pereopod overreaching antennal scale by chela and about of carpus. Remaining pereopods detached or missing in all specimens.

Eggs small and numerous, measuring about 0.5 mm in major diameter.

SIZE.—Carapace length of nonovigerous female holotype, 24.8 mm; of nonovigerous female paratype, 24.2 mm; of ovigerous female paratypes, 24.3 and 25.4 mm.

MATERIAL.—PHILIPPINES. Lagonoy Gulf, east of southern Luzon: sta 5447; 13°28′N, 123°46′18″E; 567 m; green mud; 7.4° C; 4 Jun 1909 (0614–0935); 12′ Agassiz beam trawl: 1 [24.2].

INDONESIA. West of Halmahera: sta 5624; 0°12′15″N, 127°29′30″E; 527 m; fine sand, mud; 29 Nov 1909 (1058–1118); 12′ Agassiz beam trawl: 3 [24.3–25.4], 2 ovig [24.3, 25.4], nonovigerous is holotype (USNM 211375).

TYPE-LOCALITY.—West of Halmahera, Indonesia; 0°12′15″N, 127°29′30″E; 527 m.

RANGE.—Known only from the type-series from Lagonoy Gulf, Philippines, and west of Halmahera, Indonesia, in depths of 527 and 567 m.

MATERIAL.—PHILIPPINES. Off Arangasa Islands, eastern Mindanao: sta 5236; 8°50′45″N, 126°26′52″E; 203 m; fine gray sand; 5.1°C; 11 May 1908 (1027–1102); 12′ Agassiz beam trawl, 3 mud bags: 1 [19.0].

INDONESIA. Ceram Sea south of Pulau Obi: sta 5634; 1°54′00″S, 127°36′00″E; 602 m; 3 Dec 1909 (0625–0702); 12′ Agassiz beam trawl: 5 ovig [17.9–20.8]; sta 5635; 1°53′30″S, 127°39′00″E; 732 m; coral, rock, soapstone; 3 Dec 1909 (0956–1001); 12′ Agassiz beam trawl: 1y [10.5] 1? [?].

RANGE.—Arabian Sea to Hawaii; 165–1170 meters.