Sesarma crassipes Cano 1889

Sesarma crassipes Cano, 1889

Sesarma crassipes Cano, 1889:93.

Ses[arma]. crassipes.—De Man, 1892a:261.

Sesarma crassipes.—Rathbun, 1897a:90.

Sesarma (Sesarma ss.) crassipes.—Tesch, 1917:142.

Sesarma (Sesarma) crassipes.—Rathbun, 1918:294.—Coelho and Ramos, 1972:204.

Sesarma crassipes Abele, 1979:178, figs. 1, 2.

?Sesarma crassipes.—Coelho and Ramos-Porto, 1981:178, fig. 1 [= ?S. curacaoense].

MATERIAL EXAMINED.—Costa Rica: Tortuquero, about two miles [3.2 km] above the mouth of the Tortuquero River at Leós 1, USNM 113280; Tortuquero, about two miles [3.2 km] above mouth of Tortuquero River, 1 (ovigerous), 1984, J. Rudloe.

DESCRIPTION.—Carapace broader than long (cl/cb = 0.89), indistinct granules, each with a small amount of pubescence, present on anterior and lateral regions of the carapace; sparse medially and posteriorly. Lateral margins widening slightly posteriorly. Interorbital region subdivided into four distinct lobes; median sinus deeper than submedial pair. Frontal region about 0.56 of carapace breadth; concave medially, oblique with a very small concave region to lateral margins, which flare very slightly. Distinct groove from lateral margin of frontal region extending posteriorly on the dorsal surface of carapace to about level of lateral tooth. Posterior orbital margin thickened, slightly sinuous, extending anteriorly forming a large acute, outer orbital angle. Distinct lateral tooth present on a higher level than outer orbital angle. About nine oblique granular ridges on lateral surface of carapace.

Eyes well developed, pigmented.

Basal antennular segment wide, short; palp slightly longer than width of basal segment. Basal antennal segment expanded laterally forming part of medioventral portion of orbit; ventrally forming part of Verwey's groove. Subtriangular area on pterygostomial region delimited dorsally by Verwey's groove. Suborbital region covered by short hairs.

Third maxillipeds gaping, exposing inner mouth parts; long setae present along medial edge; oblique row of pubescence on merus.

Male chelipeds strong, robust; in single specimen right slightly larger than left. Posterior mesial border of merus weakly toothed, ending in a distinct notch proximal to distal margin. Anterior mesial border strongly toothed, expanded distally. Two rows of pubescence present on mesial surface. Lateral border of merus toothed, ends in a notch proximal to distal margin. Mesial border of carpus delimited by row of tubercles at an acute angle; below angle two large and about three small tubercles; lateral border rounded and entire surface covered by short rugae. Dorsal surface of palm marked by distinct row of tubercles, extending beyond distal margin; lateral surface of palm smooth to very weakly marked by short rows of tubercles; mesial surface has about 10 large tubercles and 15 to 20 smaller tubercles that extend to and weakly delimit ventral border of palm; 8 to 12 tubercles on dorsal surface of movable finger extending from proximal margin, ending proximal to corneous, spooned tip of finger; ventrally a large, subbasal tooth and two to three smaller distal ones. Immovable finger armed with large basal tooth, subequal one distally and two weaker teeth proximal to corneous, spoon-shaped tip. Walking legs increasing in length from first, fourth, second, and third. For third walking leg (fourth pereopod) merus about twice length of carpus; carpus shorter than propodus; dactylus slightly shorter than carpus. Merus length about twice width; transverse rows of granules and large subdistal tooth on dorsal margin. Walking legs with ventral and dorsal row of thick pubescence extending from dorsal distal portion of carpus to distal margin of propodus where it extends as three narrow rows to distal portion of dactylus; ventrally row begins on distal portion of propodus and continues as three narrow rows on dactylus. Ventral surface of propodus armed with about three to five pairs of irregularly spaced dark-colored spines; on each side of ventral distal margin about four to five dark-colored spines.

Male abdomen subtriangular in outline; length and width of telson subequal. Endpiece of male gonopod short and subreclangular; shallow sinus on distolateral margin.

MEASUREMENTS.—The single available male is sexually mature and has a cb of 25.5 mm and cl of 22.2 mm. Cano (1889) stated that the male holotype has a cb of 22 mm and a cl of 18 mm. An ovigerous female has a cb of 23 and a cl of 20 mm.

TYPE.—The male holotype is presumed to be lost.

TYPE LOCALITY.—Pernambuco, Brazil.

DISTRIBUTION.—The species is known from near Tortuquero, Costa Rica, and Pernambuco, Brazil.

HABITAT.—The label accompanying the specimen from Costa Rica indicates that it was “dipnetted along shore” about two miles [3.2 km] above the mouth of the Tortuquero River at Leós (USNM 113280). Coelho and Ramos (1972) list the species from estuaries at Pernambuco. The female was found at almost exactly the same locality as the male. The surface salinity was 0°/oo, but the water at 3 m depth contained a marine fauna.