Pagurus exilis ( Benedict, 1892 )

Nucci, Paulo Ricardo & Melo, Gustavo Augusto Schmidt De, 2007, Hermit crabs from Brazil. Family Paguridae (Crustacea: Decapoda: Paguroidea): Genus Pagurus, Zootaxa 1406, pp. 47-59 : 50-53

Pagurus exilis ( Benedict, 1892)

(Figs. 1C, 2C, 3C, 4C)

Eupagurus exilis Benedict, 1892: 6 .— Barattini & Ureta, 1960: 53.

Pagurus exilis .— Forest & Saint Laurent, 1968: 135, figs 102–106.— Coelho & Ramos, 1972: 165.— Scelzo & Boschi, 1973: 208.— Boschi, 1979: 138.— Coelho & Ramos-Porto, 1986: 41.— Hebling & Rieger, 1986: 68, fig. 3.— Rieger, 1998: 414.— Melo, 1999: 126, fig. 70.

Diagnosis. Shield slightly broader than long. Rostrum triangular, with rounded tip. Ocular peduncles with median constriction; corneae dilated. Ocular acicles large, with rounded tips and small submarginal spine; dorsal face remarkably concave. Antennular and antennal peduncles overreaching corneae, approximately 2/3 as long as ultimate segment. Right cheliped elongate; palm with several conical or flattened tubercles on dorsal face, more developed near mesial margin. Left cheliped smaller than right; fingers 1.5 length of palm; dorsal face of carpus slightly convex, with midline of strong conical tubercles. Second and third pereopods strong; on dorsal and ventral faces of meri and on propodi transversal granulated grooves with short setae inserted; dactyls slightly turned inside, with median grooves on lateral faces. Telson with posterior lobes short and broad, left lobe more developed than right; posterior margins armed with irregular strong spines.

Shield and cephalic region: A, Pagurus brevidactylus ; B, P. criniticornis ; C, P. exilis ; D, P. heblingi ; E, P.

leptonyx ; F, P. limatulus ; G, P. longimanus ; H, P. provenzanoi .

Distribution. Western Atlantic — Brazil (from Rio de Janeiro to Rio Grande do Sul), Uruguay and Argentina.

Habitat. From shallow waters to 50 metres, on sandy and muddy bottoms.

Material examined. Brazil: Rio de Janeiro – Cabo Frio, 30 m, 1 male: 6.4 mm ( MZUSP –8635); 45 m, 1 male: 4.9 mm ( MZUSP –8637); 30 m, 1 female: 4.8 mm ( MZUSP –8638); Proj. Ilha Grande, st. 335, 1 male: 3.6 mm ( MZUSP –4700); st. 268, 2 males: 4.8, 3.1 mm ( MZUSP –4702); st. 294, 15 m, 1 female: 3.1 mm ( MZUSP –4696); st. 273, 2 males: 4.7, 3.6 mm ( MZUSP –4704). São Paulo – Ubatuba, Proj. Integrado, st. 29, 1 male: 4.5 mm ( MZUSP –8751); st. 15, 3 males: 5.1, 4.6, 4.7 mm ( MZUSP –8745); st. 22, 4 males: 5.5, 5.4, 5.3, 4.2 mm ( MZUSP –8749); st. 26, 3 males: 5.5, 5.0, 4.7 mm ( MZUSP –8750); st. 33, 2 females: 3.7, 3.6 mm ( MZUSP –8753); st. 14, 1 male: 5.3 mm ( MZUSP –8744); st. 20, 4 males: 4.6, 4.8, 5.5, 4.9 mm ( MZUSP – 8747); st. 42, 3 males: 5.1, 4.9, 4.5 mm ( MZUSP –8754); fixed st. 4, 3 males: 5.9, 4.8, 5.7 mm ( MZUSP – 8757); st. 18, 1 male: 6.5 mm ( MZUSP –8746); Ilha da Moela, 1 male: 4.9 mm, 1 female: 4.5 mm ( MZUSP – 7363); 2 males: 5.2, 5.2 mm ( MZUSP –7362); Santos, 36 m, 1 female: 4.6 mm ( MZUSP –7360); 1 male: 5.2 mm ( MZUSP –7361); 3 females: 4.7, 4.4, 3.5 mm, 1 male: 3.9 mm ( MZUSP –13346). Rio Grande do Sul – Proj. GEDIP, st. 409, 32 m, 1 male: 5.1 mm ( MZUSP –4698).

Remarks. Pagurus exilis is relatively close to P. longimanus (which is only found in Amapá), P. limatulus and P. heblingi . The four species are similar in the aspect of the cephalic region, but can be quickly distinguished by differences in the shape and ornamentation of the chelipeds and ambulatory legs.