Prionocrangon pectinata Faxon, 1896

Kim, Jung Nyun & Chan, Tin-Yam, 2005, A revision of the genus Prionocrangon (Crustacea: Decapoda: Caridea: Crangonidae), Journal of Natural History 39 (19), pp. 1597-1625 : 1605-1608

publication ID	https://doi.org/ 10.1080/00222930400016788
persistent identifier	https://treatment.plazi.org/id/03DC87A7-FF88-2F3E-DBEE-FA8DFCFE2CF1
treatment provided by	Felipe
scientific name	Prionocrangon pectinata Faxon, 1896
status

Treatment

Prionocrangon pectinata Faxon, 1896 View in CoL

( Figure 3 View Figure 3 )

Prionocrangon pectinata Faxon 1896, p 157 View in CoL , Plate 2 Figures 4–7 View Figure 4 View Figure 5 View Figure 6 View Figure 7 [type locality: Caribbean Sea off Martinique]; de Man 1920, p 257 (list); Chace 1984, p 56 (key).

Material examined

Caribbean Sea. Holotype: ‘‘ Blake’ ’, stn 201, off Martinique, Lesser Antilles, 14 ° 349400N, 61 ° 89250W, 1033 m, 1877–1880 survey, 1 ovig. ♀ (CL 8.2 mm), MCZ 4436.

Type material

See above.

Description

Rostrum broken distally in holotype. Mid-dorsal carina of carapace armed with eight spines ( Figure 3A View Figure 3 ). Fourth and fifth abdominal somites without median carina ( Figure 3D View Figure 3 ); sixth somite 0.50 times as long as carapace, posterior margin of posterolateral process subtruncate, lacking minute tooth but slightly produced ventrally ( Figure 3A View Figure 3 ). Telson slightly shorter than sixth abdominal somite ( Figure 3D View Figure 3 ), 0.44 times as long as carapace, posterior half strongly convergent; posterior margin subtruncate, armed with two pairs of spines but lacking median denticle ( Figure 3E View Figure 3 ). Eyestalks triangular, shortly drawn out to acute extremities, lateral margin sinuous ( Figure 3B, C View Figure 3 ). Antennular peduncle with proximal segment moderately long, 0.61 times as long as carapace ( Figure 3B View Figure 3 ). Stylocerite with tip elongate and sharp ( Figure 3B View Figure 3 ). Palm of first pereopod moderately slender, 4.61 times as long as wide ( Figure 3F View Figure 3 ). Dactyli of fourth and fifth pereopods broken or missing. Holotype ovigerous female with endopod of second pleopod moderately short, 0.33 times as long as exopod; pleopods with endopods and protopods lacking lateral lobe or distal projection.

Size

Only one ovigerous female CL 8.2 mm known.

Distribution

Caribbean Sea, at depth of 1033 m.

Colour in life

Not known.

Remarks

The holotype, and only, specimen from the Caribbean Sea is somewhat damaged ( Figure 3A, B View Figure 3 ). Faxon (1896) described the telson of the holotype as short, but this was because he did not realize that the uropods are damaged basally ( Figure 3A View Figure 3 ). The posterior margin of the telson was also described as setiferous by Faxon (1896) but the type actually bears only two pairs of spines ( Figure 3E View Figure 3 ). Supplementary characters observed in the holotype are: telson armed with three pairs of dorsolateral spines ( Figure 3E View Figure 3 ); the eyestalk bearing a small ventral denticle ( Figure 3C View Figure 3 ); and the carpus and merus of the first pereopod are armed with small distolateral and dorsodistal spines, respectively ( Figure 3G View Figure 3 ).

Prionocrangon pectinata is most similar to the new species P. demani in having triangular eyestalks, the posterolateral process of the sixth abdominal somite only sharply produced ventrally, telson armed with two pairs of posterior spines, proximal antennular segment moderately elongate, and stylocerite with elongate and sharp tip. Nevertheless, these two species can be separated by the following characters: (1) the sixth abdominal somite is shorter in P. pectinata ( Figure 3A View Figure 3 ) than in P. demani ( Figure 9D View Figure 9 ) (0.50 versus 0.60 times as long as carapace); (2) the telson is shorter and more strongly convergent in P. pectinata ( Figure 3D, E View Figure 3 ) than in P. demani ( Figure 9D View Figure 9 ) (telson 0.44 times as long as the carapace and shorter than sixth abdominal somite versus 0.64 times and longer than sixth abdominal somite); (3) the second to fifth pleopods with the endopods having a small proximolateral lobe and the protopods bearing a small distoventral projection in P. demani ( Figure 9I, J View Figure 9 ), but these lobes and projections are absent in P. pectinata .