Goreopagurus lemaitrei, Nucci, Paulo R. & De, Gustavo A. S., 2007

Nucci, Paulo R. & De, Gustavo A. S., 2007, First record of the genus Goreopagurus McLaughlin, 1988 (Crustacea: Anomura: Paguroidea) from Brazil, with description of a new species, Zootaxa 1520, pp. 51-56 : 52-55

Goreopagurus lemaitrei n. sp.

( Figs. 1 , 2 )

Material examined. Brazil, Ceará, Canopus Bank . Holotype: male 3.5 mm (MZUSP– 17645 ). Paratypes: 1 female 3.0 mm (MZUSP– 17646 ) ; 7 females 2.6 mm, 2.8 mm, 3.0 mm, 2.4 mm (ovigerous), 2.6 mm, 2.3 mm, 2.1 mm, and 1 female with shield broken ( MZUSP –17647). All specimens were collected at 350–400 m.

Description. Shield as long as broad ( Fig. 1 A). Anterior margins between rostrum and lateral projections somewhat concave to almost straight; dorsal surface slightly rugose in the anterior half. Rostrum obtusely triangular, with or without small terminal spinule. Lateral projections rounded or slightly triangular.

Ocular peduncles approximately 0.6 length of shield, moderately stout; dorsal face with row of 3 tufts of setae, 1 tuft of setae on mesial margins, near posterior margin of corneae; corneal diameter approximately 0.4 peduncular length. Ocular acicles triangular, with strong submarginal spine; dorsal surface concave. Antennular peduncles overreaching distal margins of cornea by approximately half-length of ultimate segment.

Antennal peduncles overreaching distal corneal margins by approximately 0.4 length of ultimate segments. Fifth segment with row of long stiff setae on ventral margin. Fourth segment with or without 2 stiff setae on ventromesial face. Third segment with scattered stiff setae on ventral margin and acute spine on ventrodistal margin. Second segment with dorsolateral distal angle produced, terminating in acute spine, mesial margin unarmed or slightly serrulate on distal region, and sometimes with very small setae; dorsomesial distal angle with well-developed spine. First segment with small tooth on dorsodistal margin, sometimes hidden below the shield. Antennal flagella long, reaching or slightly overreaching tip of right cheliped; articles each usually with 3 short setae.

Right cheliped very elongate. Dactyl approximately as long as palm in male (holotype) ( Fig. 1 B), approximately 0.8 or same length of palm in females ( Fig. 1 C); cutting edge with 3 or 4 calcareous teeth in proximal half, 1 broad calcareous tooth and row of very small corneous teeth in distal third, terminating in small corneous claw; dorsomesial margin with row of denticles and 3 small teeth on distal region (in male); row of tufts of setae near cutting edge. Palm shorter than carpus, smooth, glabrous in male and small females, with very small setae in large females; dorsomesial margin with row of very small spinules or denticles on anterior half; dorsolateral margin unarmed, dorsal surface smooth; cutting edge of fixed finger with 2 or 3 calcareous teeth, terminating in corneous claw, row of tufts of setae near cutting edge, and scattered tufts of setae on distal region. Carpus longer than merus, produced ventrally; dorsomesial margin expanded to strongly expanded, armed with row of very small spines, row of setae especially dense in more-expanded region, dorsal surface smooth and glabrous, dorsolateral margin not distinctly delimited. Merus subtriangular, dorsal surface with row of setae and some scattered setae; ventrolateral and ventromesial margins each with row of spines, stouter on ventromesial margin.

Left cheliped ( Fig. 1 D, 1E) long and slender; dactyl and fixed finger arched ventrally; dactyl approximately 3.0 length of palm; cutting edge with row of tiny corneous teeth, terminating in corneous claw; dorsolateral margin with row of setae, dorsal surface with some scattered setae; palm approximately 0.3 length of carpus; dorsomesial margin with few setae, dorsal surface smooth, convex and with few scattered setae; dorsolateral margin not distinctly delimited; ventrolateral margin with row of sparse setae; cutting edge of fixed finger with row of tiny corneous teeth, terminating in corneous claw; dorsomesial region with row of corneous spines proximally (in male, very small spines; or spines absent in females); scattered tufts of setae on dorsal and ventral surfaces; carpus approximately as long as merus; dorsal surface slightly flattened, dorsomesial and dorsolateral margins each with row of setae; mesial face with few scattered setae; ventrolateral margin with 3 spines distally (in male, only few protuberances; or unarmed in females); ventral surface with 2 rows of setae. Merus with sparse setae on dorsal surface; ventrolateral margin with row of stout spines; ventromesial margin with row of long setae on distal half and row of stout spines with interspersed long setae on proximal half in male, in females these spines are smaller and slender.

Ambulatory legs ( Fig. 2 ) similar from left to right. Dactyls approximately as long as or slightly longer than propodi; dorsal margins each with row of short stiff setae, dorsomesial face with row of small corneous spines increasing in size distally; ventral margins each with row of 10–15 corneous spines; lateral faces each with very weak longitudinal sulcus. Propodi 1.6–1.8 length of carpi, each with 1 or 2 corneous spines at ventrodistal angle; row of sparse small stiff setae on each ventral margin; dorsal surface with row of strong stiff setae. Carpi each usually with 2 stiff setae on ventral margin distally and medially; dorsal surface with few stiff setae. Meri with few tufts of stiff setae on dorsal surface and sparse strong stiff setae on ventral margins; lateral face with longitudinal sulcus (only in the first pair of ambulatory legs).

Anterior lobe of sternite of third pereopods semirectangular with rounded angles (in male) to subovate (in females), with stiff bristles on anterior margin.

Males without sexual tube on either coxa of fifth pereopods; unpaired left pleopods 3–5 with endopods reduced. Females with paired modified first pleopods; unpaired left pleopods 2–4 with endopods stout, fifth pleopod with endopod reduced. Uropods asymmetrical ( Fig. 1 G).

Telson ( Fig. 1 G) with posterior lobes separated by deep median cleft, terminal margins oblique, each usually with 3 small spines, lateral margins delimited by narrow chitinous band.

Etymology. It is a pleasure to name this species in honor of Rafael Lemaitre (National Museum of Natural History, Smithsonian Institution) in recognition of his great contributions to knowledge of the worldwide Anomura, especially the Paguroidea.

Distribution. Known only from the type locality, off Fortaleza, Ceará, Brazil.

Figures

FIGURE 1. Goreopagurus lemaitrei n. sp. A, Shield and cephalic region (paratype female, MZUSP- 17646); B, right cheliped (holotype male, MZUSP- 17645); C, right cheliped (paratype female, MZUSP- 17646); D, left cheliped (dorsal view, holotype male, MZUSP- 17646); E, left cheliped (ventral view, holotype male, MZUSP- 17646); F, left cheliped (paratype female, MZUSP- 17646); G, uropods and telson (paratype female, MZUSP- 17646).

FIGURE 2. Goreopagurus lemaitrei n. sp. A, Left third pereopod (lateral view); B, left second pereopod (lateral view); C, right second pereopod (lateral view); D, right third pereopod (lateral view); E, left second pereopod (mesial view); F, left third pereopod (mesial view); G, right third pereopod (mesial view); H, right second pereopod (mesial view). A-H (paratype female, MZUSP- 17646).