Rhopalurus crassicauda paruensis, Lourenço, 2008

Lourenço, Wilson R., 2008, The geographic pattern of distribution of the genus Rhopalurus Thorell, 1876 in the Guayana-Amazon region (Scorpiones: Buthidae), Euscorpius 73 (73), pp. 1-14 : 7-9

Rhopalurus crassicauda paruensis ssp. n.

( Figs. 5–9 )

Male holotype: Brazil, state of Pará , Campos de

Paru, South of the Serra do Tumucumaque, border with Suriname, X/1966 (F. Petter). Deposited in the Muséum national d’histoire naturelle, Paris (RS-8630).

Etymology: The subspecific name makes reference to the Campos of Paru in state of Pará.

Diagnosis: Small scorpion in relation to the species of the genus, with 41.2 mm in total length. Very pale coloration, yellowish to pale yellow. Pectinal tooth count 25–25; fixed and movable fingers of pedipalps with 7–8 rows of granules.

Relationships: This subspecies is clearly related to R. crassicauda . It is distinguished, however, by a much paler general coloration with the absence of a solid blackish stripe on the ventral aspect of metasomal segments.

Description based on male holotype. Measurements in Table 1.

Coloration. Basically yellowish to pale yellow. Prosoma: carapace yellowish with an inverted triangular pale reddish spot stretching from the median eyes to the lateral eyes; eyes surrounded with black pigment. Mesosoma: yellowish. Metasoma: segments I to IV yellowish; V reddish-yellow; segments IV–V moderately infuscate. Vesicle of same color as segment V. Venter pale yellow. Chelicerae yellowish with a pale thread; fingers reddish-yellow. Pedipalps: pale yellow; granulations on the edge of fingers reddish. Legs pale yellow.

Morphology. Carapace moderately granular; anterior margin with a median concavity. Anterior median and posterior median carinae moderate to weak. All furrows moderately deep. Median ocular tubercle distinctly anterior to the center of the carapace. Eyes separated by one ocular diameter. Three pairs of lateral eyes. Sternum subtriangular. Mesosoma: tergites moderately to strongly granular. Median carina moderate in all tergites. Tergite VII pentacarinate. Venter: genital operculum divided longitudinally, forming two oval plates. Pectines: pectinal tooth count 25–25. Sternites smooth with elongate spiracles; sternite VII with four carinae and a thin granulation. Metasoma: segments I to III with 10 carinae; IV with 8 carinae; V with 5 carinae. Intercarinal spaces moderately granular on segments I to III; strongly granular on IV–V. Telson roughly granular with a long and curved aculeus. Subaculear tooth reduced and conical. Cheliceral dentition characteristic of the family Buthidae ; ventral aspect of both fingers and manus with dense, long setae ( Vachon, 1963). Pedipalps: femur pentacarinate; patella with 7 carinae; chela with 9 carinae, moderate to vestigial; internal aspect of patella with spinoid granules; all faces weakly granular. Fixed and movable fingers with 7–8 oblique rows of granules. Internal and external accessory granules intensely marked. Trichobothriotaxy; orthobothriotaxy A-α (Vachon, 1974, 1975). Legs: tarsus ventrally with numerous short fine setae.

Ecology: The type specimen of R. crassicauda paruensis ssp. n. was collected in a “Campo firme” formation. A gradient of Cerrados also defined as “dry campo”. This gradient can present trees and shrubs forming a sparse to open cover (Eiten, 1978). The scorpion was collected under the bark of a tree ( Bowdichia sp. ), about 1.5 m from the ground.

Figures

Figures 5–9: Rhopalurus crassicauda paruensis ssp. n., male holotype. 5–7. Chela, dorso-external, ventral and internal aspects, showing trichobothria. 8–9. Tarsi of leg IV, lateral and ventral aspects, showing setation.