Cuneimelita danielle

Senna, André R. & Serejo, Cristiana S., 2012, A new genus and species of Melitidae (Crustacea: Amphipoda: Hadzioidea) from Brazilian waters, Zootaxa 3433, pp. 60-68 : 61-66

Cuneimelita danielle gen. et sp. nov.

( Figs 1–4 )

Material examined. Holotype: 1 male, dissected and drawn in glycerol gel slide, Rio Grande do Sul, Brazil, 30º42’S 50º06’W, 70 m, 22-vi-1968, box-corer, GEDIP Project, N. Oc. Prof. W. Besnard col., MNRJ 23138.

Paratypes: three specimens, in ethanol 70%, Campos Basin, Rio de Janeiro, Brazil, 22º19’11”S 40º05’44”W, 404 m, 08-vi-2008, box-corer, Habitats Project (slope), R/V Gyre col., MNRJ 23139; 4 specimens, in ethanol 70%, Rio Grande do Sul, Brazil, 29º30’S 48º57’W, 20 m, xii-1968, box-corer, GEDIP Project, N. Oc. Prof. W. Besnard col., MNRJ 23140; 5 specimens, in ethanol 70%, Rio Grande do Sul, Brazil, 32º27’S 50º22’W, 57 m, 26-viii-1968, box-corer, GEDIP Project, N. Oc. Prof. W. Besnard col., MNRJ 23141; 1 specimen, in ethanol 70%, Rio Grande do Sul, Brazil, 30º10’S 48º58’W, 132 m, xii-1968, box-corer, GEDIP Project, N. Oc. Prof. W. Besnard col., MNRJ 23142; 2 specimens, in ethanol 70%, Rio Grande do Sul, Brazil, 30º42’S 50º06’W, 70 m, 22-vi-1968, box-corer, GEDIP Project, N. Oc. Prof. W. Besnard col., MNRJ 23143.

Etymology. The name of this species is a noun in apposition, and is dedicated to Danielle P. Cintra, wife and companion of the first author (ARS).

Diagnosis. Same as for the genus.

Description. Head as deep as long. Rostrum absent, lateral cephalic lobe rounded, anteroventral margin retracted, without notch or fissure. Eyes poorly developed, rounded. Antenna 1 elongate, more than half length of body, article 1 of the peduncle elongate, ventral margin with a thick distal seta. Antenna 2 about half of the antenna 1, with few setae. Mandible, incisor bifid and multi-cuspidate, lacinia mobilis well developed, apical margin with poorly defined cusps, molar well developed, subtriturative; palp 3-articulate, article 1 approximately 2× longer than wide, article 2 thin, about 6× longer than wide, article 3 thin, about 6× longer than wide, about 0.9 × the length of article 2. Lip with inner lobes poorly developed. Labrum rounded, minutely setose apically. Maxilla 1, inner plate subtriangular, inner margin without setae, with 2 simple apical setae; outer plate subrectangular, apical margin with 7 stout setae, palp 2-articulate, article 2 broad, apical margin setose. Maxilla 2, inner plate subrectangular, marginal row of setae absent, facial row of setae absent; outer plate slightly wider than the inner plate, outer margin distally setose, apical margin setose, posterodistal angle with a long thin seta.

Gnathopod 1, coxa wider than long, strongly produced anteriorly, anterior margin concave; base subrectangular, with 2 long setae and 1 small at posteroventral angle; merus, posterodistal angle produced and subacute; carpus about 1.3 × longer than wide, smaller than the propodus, ventrally setose, with a lateral row of setae; propodus about 1.3 × longer than wide, 1.5 × length of carpus, wedge-shaped, subtriangular, anterior margin convex, palm larger than posterior margin, carrying 7 stout setae irregularly distributed; dactyl stout, reaching palmar angle, outer margin without setae. Gnathopod 2, subequal in form to gnathopod 1 but slightly larger; coxa subquadrate; carpus subtriangular, approximately 1.2 × wider than long, dorsal margin with medial concavity; propodus robust, about 1.9 × length of carpus, palm with 9 stout setae irregularly distributed; dactyl, inner margin setose, outer margin with single thin seta. Pereopod 3, coxa slightly elongated; base subrectangular; merus and carpus, posterior margins densely setose; propodus thin, posterior margin with row of stout setae; dactyl simple, slender and elongate. Pereopod 4, subequal to pereopod 3, coxa subquadrate with posteroventral lobe poorly defined. Pereopods 5–7, base with distal anterior margin setose, posterior margin smooth, posteroventral lobe absent; basis of pereopods 5–6 unexpanded posteriorly; base of pereopod 7 moderately expanded posteriorly.

Pleon and urosome dorsally smooth. Epimeral plates 1–2, ventral margin setose, posteroventral angle slightly produced, subacute. Epimeral plate 3, ventral margin setose, posteroventral angle produced in a spine strong and sharp, curved upwards. Urosomites 1–3 without dorsal setae or spines. Uropod 1, peduncle about 2.8 × longer than wide, basofacial stout seta present, dorsal margin covered by thick row of setae, distolateral angle bearing strong, stout seta, rami subequal in length, approximately 0.7 × length of peduncle, dorsal margin distally setose. Uropod 2, approximately 0.7 × length of uropod 1; peduncle subrectangular, rami carrying stout setae dorsally, outer ramus slightly smaller than inner ramus and approximately subequal in length to peduncle. Uropod 3, inner ramus reduced, outer ramus 1-articulate, apically truncated, approximately 4 × length of inner ramus and 2 × length of peduncle. Telson wider than long, deeply cleft, approximately 60% of length, lobes rounded, without apical setae, with 2 small thick dorsolateral setae and a little thin curved seta on lateral margin of each lobe.

Figures

FIGURE 1. Cuneimelita danielle gen. et sp. nov., male, holotype, Rio Grande do Sul, Brazil, 30 º 42 ’ S 50 º 06 ’ W, MNRJ 23138. Scale bars: 0.5 mm for Hd; 0.1 mm for the remainder.

FIGURE 2. Cuneimelita danielle gen. et sp. nov., male, holotype, Rio Grande do Sul, Brazil, 30 º 42 ’ S 50 º 06 ’ W, MNRJ 23138. Scale bars: 0.5 mm.

FIGURE 3. Cuneimelita danielle gen. et sp. nov., male, holotype, Rio Grande do Sul, Brazil, 30 º 42 ’ S 50 º 06 ’ W, MNRJ 23138. Scale bars: 0.5 mm.

FIGURE 4. Cuneimelita danielle gen. et sp. nov., male, holotype, Rio Grande do Sul, Brazil, 30 º 42 ’ S 50 º 06 ’ W, MNRJ 23138. Scale bars: 0.1 mm for T; 0.5 mm for the remainder.