Gyneleucon tripedium Brito & Serejo 2023, sp. nov.
Creators: name: Brito, Ayrton Do Ramo
name: Serejo, Cristiana Silveira
Publisher: name: Zenodo
Year: 2023
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Malacostraca
Cumacea
Leuconidae
Gyneleucon
Gyneleucon tripedium

description: Gyneleucon tripedium sp. nov.
(Figs. 14 and 15)
Material examined. Holotype (lost inthe 2018 fire): Figures 14 and 15, based in male, 1.9 mm, # AMB14 F3, MNRJ 28968.
Additional material (lost in the 2018 fire): male, 2.1mm, # AMB 7 C2, MNRJ 28965; male, 2 mm, # AMB 7 F3, MNRJ 28964; male, 2.0 mm, # AMB 14 C2 MNRJ 28966; male, 2 mm, #HAB17 B2; MNRJ 28969.
Development. Mature males longer than 1.9 mm.
Type locality: Espírito Santo Basin, Espírito Santo, Brazil, 18°53’31’’S – 39°6’21’’W, 51 m.
Distribution: Brazil; Campos Basin (RJ) and Espírito Santo Basin (ES), 39– 53 m.
Etymology. Tri from the Greek tria (three) + pedium from Latin (feet in genitive case) seeing that males present exopods only at pereopods 1–3.
Diagnosis. See diagnosis of genus.
Description: Based on holotype, 1.9 mm, MNRJ 28968.
Mature male, 1.9 mm. Carapace about 1.2 times pereon length including pseudorostrum, may present very small dorsal serration, frontal margin with single tooth; pseudorostrum acute, 0.3 times carapace length (measured from frontal lobe to posterior margin), with distal setae and teeth; antennal notch absent; anteroventral corner rounded with 2 teeth (Fig. 14 and 15).
Pleon longer than 0.5 times total body length (Fig. 15).
Antenna 1, geniculate between articles 1 and 2; article 1, as long as article 2 and 3 together, naked; article 2 and 3 subequal in length, both with few distal simple setae; main flagellum of 3 articles, article 1 naked, article 3 with 3 simple setae and 2 aesthetascs; accessory flagellum of 1 article, longer than main flagellum article 1 (Fig. 14 a 1).
Antenna 2 with brush of setae on article 4 and 5 outer margin, flagellum extending until pereonite 2 (Fig. 14 a 2).
Mandibles, basis truncate, incisor with 2 distal simple setae, lacinia mobilis with 3 cusps (Fig. 14 md).
Maxilla 1 with 2 endites, palp with one bristle (broken during dissection) (Fig. 14 mx1).
Maxilla 2 with 3 endites; broad endite with row of distal plumose setae; narrow endites with simple setae (Fig. 14 mx2).
Maxilliped 1, accidentally destroyed during dissection.
Maxilliped 2, basis broken during dissection; merus with plumose setae on distal inner margin; carpus with 5–6 plumose setae along inner margin; propodus with long plumose seta and distal simple setae; dactylus with strong terminal and subterminal simple setae (Fig. 14 mxlp2).
Maxilliped 3, basis 1.4 times length of remaining articles together, with plumose setae on inner margin, distolateral corner with 3 plumose setae; ischium naked; merus with plumose setae at outer distal corner; carpus with plumose seta at outer corner and plumose setae on inner margin; dactylus with strong terminal seta and 2 subterminal simple setae; exopod flagellum with 5 articles (Fig. 14 mxlp3).
Pereopod 1, basis 0.7 times length of remaining articles together, with plumose setae; ischium, with tooth at inner corner; merus, carpus and propodus, with plumose and simple setae; dactylus with pair of terminal setae and pair of subterminal setae. Exopodal flagellum, with 6 articles (Fig. 15 p 1).
Pereopod 2, basis 1.25 times length of remaining articles together, with plumose setae; ischium absent; merus, with simple setae; carpus, with simple setae; propodus naked; dactylus, with simple setae. Exopodal flagellum, with 5 articles (Fig. 15 p 2).
Pereopod 3, basis 1.5 times length of remaining articles together with plumose setae; ischium with simple seta; merus, with simple setae; carpus, with simple and annulate setae; propodus, with simple seta; dactylus small, with long simple setae. Exopod, flagellum with 5 articles (Fig. 15 p 3).
Pereopod 4, basis as long as remaining articles together, with plumose setae; ischium, with plumose setae; merus, with simple seta; carpus and propodus with simple seta; dactylus small with long simple seta. Exopod absent (Fig. 15 p 4).
Pereopod 5, basis 0.5 times length of remaining articles together, with simple seta; ischium naked; merus, carpus and propodus, with simple seta; dactylus small, with simple long seta (Fig. 15 p 5).
Uropod, peduncle longer than pleonite 6 with 4 cuspidate setae on inner margin; endopod 2-articulate, article 1, 2.5 times article 2 length, with 6 cuspidate setae on inner margin, article 2 with 2 cuspidate setae on inner margin and 3 terminal setae; exopod as long as endopod, with 5 distal simple setae and simple seta on inner margin (Fig. 15 u).
Remarks: See remarks on the genus.
description: Published as part of Brito, Ayrton Do Ramo & Serejo, Cristiana Silveira, 2023, Leuconidae Sars, 1878 (Crustacea: Cumacea) from the southwestern Atlantic, filling the distribution gap along the Brazilian coast, pp. 101-134 in Zootaxa 5383 (2) on pages 126-128, DOI: 10.11646/zootaxa.5383.2.1, http://zenodo.org/record/10350586