Trichocaris, 2020

TRICHOCARIS VERESHCHAKA & KULAGIN , GEN. NOV.

LSID:

Z o o b a n k. o r g: a c t: 1 2 3 4 2 5 E B - 5 E 4 6 - 4 4 F 8- 8F 7F - F2754A295850.

Diagnosis: Integument membraneous; carapace with developed submarginal branchiostegal spine set behind anterior margin, no hepatic spine; pleon with fourth to sixth somites dorsally carinate, fourth somite posteriorly entire, sixth somite posterodorsally straight; telson with posterior, triangular end-piece between apical spines, with two to three pairs of moveable dorsolateral spines and a single pair of apical spines. First maxilliped with exopod distally gently tapering to tip; second maxilliped expanded moderately, more than three times as long as broad; third maxilliped with subrectangular dactylus bearing several strong spines at tip. First pereopod with basis and ischium unarmed; fourth and fifth pereopods with dactyl slender, entire. Thelycum without median tooth on S6 or S8, no posterior setose protuberances on S6, S7 as a trapezoid scutum covered with tufts of sensory setae, no additional posteriorly directed scutum, S8 with tufts of sensory setae extending from deep invaginations. Petasma as simple unarmed lamina, PE distally produced.

Species included: Trichocaris bartletti (Smith, 1882) , comb. nov., T. tanneri (Faxon, 1893) , comb. nov., T. tirmiziae (Crosnier, 1978) , comb. nov.

Type species: Benthesicymus bartletti Smith, 1882 .

Etymology: From Greek τριχωτός, hairy, and καρίς, shrimp, a reference to the characteristic dense tufts of setae covering thelyca of the species included.

Authorship of generic name: The phylogenetic basis for the erection of this genus was prepared by Vereshchaka & Kulagin, who are thus solely responsible for making the generic name Trichocaris available.

Remarks: The species included are similar in the morphology of the copulatory structures, especially of the petasma, and in other external characters. A remarkable difference between species is related to the armature of the fifth pleonic somite. Petasma and thelycum of T. bartletti are illustrated by Pérez Farfante & Kensley (1997: fig. 27) under the name Bentheogennema intermedia (mistake in the figure caption).

Geographical distribution: Three species show a distribution similar to parapatric: T. bartletti is known from the North and Central Atlantic and Indo-West Pacific, T. tanneri occurs in the East Pacific and T. tirmiziae has been recorded from the Indo-West Pacific. Thus, the only reported area where two species co-occur is the Indo-West Pacific ( T. bartletti and T. tirmiziae ).