Sesarma rubinofforum Abele 1973

Sesarma rubinofforum Abele, 1973

Sesarma (Holometopus) rubinofforum Abele, 1973b:333.

Sesarma rubinofforum.—Abele, 1976:268.—Hagen, 1978:51.—Abele, 1981:438.

MATERIAL EXAMINED.—Panama: Pacific coast, Canal Zone, Diablo Heights, mangrove swamp on east bank of Panama Canal, 18 Feb 1969, L.G. Abele, LGA 69–30, 1 paratype, cb 6.7 mm, UPRC; 1 ovigerous paratype, cb 8.4 mm (illustrated, Figure 21), USNM; Panama, locality data as above, salinity 22.4‰, temperature 27.9°C, 25 Jan 1971, L.G. Abele, T.A. Biffar, LGA 71-5, male holotype, cb 8.8 mm, 5 paratypes, cb 3.3–10.4 mm, 4 paratypes, cb 6.0–8.8 mm, USNM; 1 cb 8.0 mm, 1, cb 7.8 mm (paratypes), RMNH; 1, cb 6.8 mm, 1, cb 7.0 mm (paratypes), AHF.

DESCRIPTION.—Carapace broader than long (c1/cb= 0.858±0.31 in males, 0.853±0.43 in females), narrowing posteriorly. Frontal region subparallel about 0.60 of carapace width; frontal margin sinuous with broad median depression.

Interorbital region with four distinct lobes; lateral (outer) lobes indistinctly subdivided into two lobes by two patches of pubescence. Regions of carapace distinct. Dorsal and lateral surfaces of the carapace with patches of short, brown pubescence. Outer orbital angle acute; no tooth or lobe posterior to it. About four granular ridges on lateral surfaces of carapace.

Eyes well developed and pigmented.

Merus of chelipeds with margins distinctly serrate; subdistal lobe present on lateral margin. Many subacute granules along border of carpus and dorsal surface; no tooth or lobe at medial angle. A strong granulate ridge extends length of dorsal surface of palm; weakly bifurcate proximally. Other poorly defined rows of granules arise from this ridge and extend onto medial surface of palm. Lateral surface of palm smooth except for a few scattered granules. Movable finger subequal in length to palm; about seven strong, acute tubercles along dorsal surface of finger, median ones strongest.

Walking legs robust with the third (fourth pereiopod) being longest. Length of merus of third about 1.9 times width; superior borders with minute widely spaced teeth and a strong, acute subdistal tooth; inferior border smooth. Short horizontal rows of granules present on meri of walking legs. Carpus with scattered setae on dorsal surface of propodus and less on ventral surface; three pairs of strong, black spines on distal inferior margin. Dactylus with three dorsal and two ventral poorly defined rows of pubescence. Merus slightly less than twice length of carpus; carpus subequal in length to propodus. Dactylus slightly shorter than both propodus and carpus.

Male abdomen subtriangular in shape, narrowing distally from third segment. Telson broadly rounded; length and width subequal. Male gonopod simple, unarmed; endpiece (amber-colored apex) rectangular, directed laterally and covered with simple setae. Female abdomen subcircular in outline. Gonopore small, crescent-shaped area adjacent to operculum.

VARIATION.—Females have less pubescence on the carapace than males; the female chelae are not as robust as those of males, the tuberculation is weaker, and there are three or four rather than seven or eight tubercles on the dorsal surface of the movable finger.

MEASUREMENTS.—Immature males have a cb of about 3.3 mm; immature females, cb 6.0 to 6.3 mm; mature males, cb 6.2 to 10.4 mm; mature females, cb 7.0 to 8.4 mm; ovigerous females, cb 8.8 to 9.0 mm; eggs small and numerous, diameter 0.3 to 0.5 mm.

TYPE LOCALITY.—Pacific coast of Panama on the east bank of the Panama Canal in a mangrove swamp near Diablo Heights, Canal Zone.

TYPE.—The male holotype is deposited in the National Museum of Natural History.

DISTRIBUTION.—Pacific coast of Costa Rica and Panama.

HABITAT.—The specimens were collected from damp areas beneath litter deep inside a mangrove swamp composed primarily of Rhizophora mangle L. Salinity in the swamp varies from 16‰ to 24‰. Air temperature varies from about 27°C to 29°C.