Glyphocrangon singularis, Han, Qingxi & Li, Xinzheng, 2014

Han, Qingxi & Li, Xinzheng, 2014, Two new species of Glyphocrangon (Decapoda: Caridea: Glyphocrangonidae) from the East China Sea and the Philippines, Zootaxa 3852 (4), pp. 438-444 : 439-440

Glyphocrangon singularis sp. nov.

( Figs. 1 , 2 )

Glyphocrangon fimbriata— Han & Li, 2007: 547, fig. 2.

Type material. Holotype, male (cl 12.6 mm), East China Sea, MBM188838, CN V567B-16, stn. 27, 26°35′N, 126°35′E, 1680–1710 m, soft mud, AT, 8 Jun 1978.

Description (Holotype). Body slender. Integument of carapace and abdomen covered with very short, sparse setae.

Rostrum ( Fig. 1 A, B) long, about 0.85 times of carapace length, somewhat upturned in distal 0.3; dorsal surface without transverse septa, with long middorsal carina; lateral margin with 2 teeth, anterior tooth anterior to cornea. Carapace ( Fig. 1 A, B) about 1.3 times longer than wide. Anterior first carina composed of 6–7 blunt and subacute tubercles; posterior first carina composed of 4 blunt teeth. Intercarinal space between anterior first carina bearing row of about 10 small tubercles, posterior intercarinal space between posterior first carina bearing only 2 tubercles. Anterior second carina composed of 3 acute teeth, anteriormost tooth largest and most acute. Posterior second carina composed of 7–8 continuous tubercles. Anterior third carina confined to antennal spine, tracing represented by 3 small tubercles present on upper part of hepatic region. Posterior third carina entire, terminating in smooth projection. Anterior fourth carina notched by shallow groove, not continuous with branchiostegal spine. Posterior fourth carina almost paralleled with posterior third carina, without tooth on anterior end, continued by some small disperse tubercles. Posterior fifth carina composed of irregular tubercles. Intercarinal space bearing small and inconspicuous tubercles, arranged in 2–3 rows.

All abdominal somites ( Fig. 1 A, B) bearing middorsal carina, notched from second abdominal somite to sixth abdominal somite. Middorsal carina of first abdominal somite terminating anteriorly in acute, large spine, bearing row of tubercles arranged at posterior margin; submedian carina terminating anteriorly in blunt tooth; intercarinal space bearing some small and inconspicuous tubercles. Pleuron of second abdominal somite armed with 3 ventral spines, with middle spine largest. Pleuron of third abdominal somite armed with 2 ventral spines, posterior spine larger and more acute. Middorsal carina of fourth abdominal carina notched at anterior 1/3, pleuron armed with 2 ventral spines. Middorsal carina of fifth abdominal somite notched at anterior 1/5, pleuron armed with 2 ventral spine; posterior tooth 2.0 times larger than anterior one. Middorsal carina of sixth abdominal somite notched by transverse at anterior 0.4; lateral carina composed of 3–4 tubercles. Telson ( Fig. 1 A, B) about 0.8 times as long as carapace.

Eye ( Fig. 1 A, B) moderately large, maximum diameter about 0.25 times of carapace length.

Antennal scaphocerite ( Fig. 1 A, B) about 0.45 times as long as carapace, with lateral tooth.

Third maxilliped ( Fig. 2 A) slightly overreaching distal margin of scaphocerite; marginal spines on distal 2 segments slender.

First pereopod ( Fig. 2 B) without tufts of short setae on lateral surface of palm. Second pereopod ( Fig. 2 C, D) with dactylus distinctly longer than immovable finger; left carpus composed of 22 articles, right composed of 24 articles. Third pereopod ( Fig. 2 E, F) with dactylus bearing fringe of setae. Fourth to fifth pereopods ( Fig. 2 G, H) with dactylus simple, acuminate, bearing fringe of seate. Second pleopod ( Fig. 2 I) with endopod shorter than appendix masculine.

Coloration in life. Unknown.

Distribution. So far only known from the type locality in the East China Sea, at the depths of 1680–1710 meters.

Etymology. Drived from the Latin singularis , meaning single or alone, in reference to the rarity of this species.

Remarks. The new species closely resembles Glyphocrangon fimbriata Komai & Takeuchi, 1994 ( Komai & Takeuchi, 1994; Komai, 2004) in the presence of fringe of setae on dactyl of the third to fifth pereopods. In fact, we misidentified the specimen as G. fimbriata ( Han & Li, 2007) . The new species differs from G. fimbriata by the following characters: 1) the rostrum is distally moderately upturned, distinctly overreaching the anterior margin of the scaphocerite, about 0.85 times as long as the carapace length, with a longer median carina extending from apex of rostrum to the anterior groove on carapace, whereas in G. fimbriata , the rostrum is strongly upturned anteriorly, about 0.55–0.72 times as long as the carapace length, somewhat descending and then noticeably upturned in distal 0.3, and median carina extending from apex of rostrum level of anterior pair of lateral teeth; 2) two rows of tubercles are present between the two first carinae, each one close to each of these carinae on the carapace, whereas in G. fimbriata , the median area between the first carinae is smooth except for few tubercles in anterior area on the carapace; 3) anterior fourth carina on the carapace notched by shallow groove, without tooth on the anterior end, whereas in G. fimbriata , the anterior fourth carina on the carapace is separated into 2 sections by a distinct notch and posterior section terminated anteriorly in blunt tooth; 4) posterior end of first carina is not overhanging posterodorsal margin of carapace, whereas in G. fimbriata , the posterior end of first carina is distinctly overhanging the posterodorsal margin of carapace.

Figures

FIGURE 1. Glyphocrangon singularis sp. nov., holotype, male (cl 12.6 mm), MBM 188838, East China Sea, body. A, lateral view; B, dorsal view. Scale bar = 1 mm.

FIGURE 2. Glyphocrangon singularis sp. nov., holotype, male (cl 12.6 mm), MBM 188838. A, right third maxilliped, lateral view; B, right first pereopod, ventral view; C, right second pereopod, lateral view; D, palm of second pereopod, lateral view; E, left third pereopod, lateral view; F, dactylus of third pereopod, lateral view; G, left fourth pereopod, lateral view; H, left fifth pereopod, lateral view; I, second male pleopod, ventral view. Scale bars = 1 mm (A – C, E, G – I); 0.2 mm (D, F).