Oiclus purvesii (Becker, 1880)

Teruel, Rolando & Madden, Hannah, 2012, The scorpions (Arachnida: Scorpiones) of Sint Eustatius, Lesser Antilles, Euscorpius 145 (145), pp. 1-9 : 5-8

Oiclus purvesii (Becker, 1880)

Figures 6–7 , 8c–d

Records: The Quill (17°28.557N, 62°58.416W), 6 January 2010, A. Sánchez, J. Burgess, 1♀, 6 juveniles ( RTO: Sco-0459). September–October 2010, H. Madden, J. Morpeth, 2♂♂, 5♀♀, 3 juveniles ( RTO: Sco- 0521) .

Ecological Notes: so far specimens of this species have only been discovered in and around The Quill, with a distribution stretching from the lower slopes to inside the crater. In general, adult specimens were located in and around small burrows on the hiking trails, whereas juveniles were mostly located under rocks. It has been found in the following vegetation types: thorny woodland, dry evergreen forest, deciduous seasonal forest, semi-evergreen seasonal forest, evergreen seasonal forest, and pioneer forest.

Capturing specimens proved somewhat more difficult because of two factors. Firstly, Oiclus resides in burrows at ground level, waiting at the entrance for prey to pass, therefore giving them a quick escape route. Secondly, they can see the UV light (unlike the two buthids), which caused them to retreat into their burrow and made it difficult to make a capture. The same behavior has been observed in other Caribbean diplocentrines (R. Teruel, pers. obs.).

Comments: the genus Oiclus Simon, 1880 , was considered to include a single polytypic species until very recently, when two additional new species were described (Teruel, 2008; Teruel & Chazal, 2010). The specimens herein examined match the redescription of Oiclus purvesii purvesii given by Francke (1978), but we refrain from assigning the Sint Eustatius specimens to a subspecies because the validity and scope of the two subspecies of O. purvesii plus the supposedly hybrid population from Saint Kitts recognized by Francke (1978), are not satisfactory and need to be revised (Teruel & Francke, 2006).

This implies the first record of the genus Oiclus and the family Scorpionidae form Sint Eustatius. It was expected, however, because populations had already been recorded from the neighboring islands of Saba and Saint Kitts (Francke, 1978; Sissom & Fet, 2000; Teruel & Francke, 2006).

Key to the species of scorpions occurring in

Sint Eustatius

1.- Pedipalps and metasoma short and robust. Coloration basically brown, densely spotted with black, so the scorpion looks uniformly dark to blackish to unaided eye. Trichobothrial pattern C: femur with only three trichobothria, patella with three ventral trichobothria. Sternum type 2: widely hexagonal, with a posterior emargination and convex lateral lobes. Leg tarsomere II ventrally with two parallel rows of stout spiniform seta…………… …….…….…. ( Scorpionidae )………..… Oiclus purvesii - Pedipalps and metasoma long and slender. Coloration basically yellow, sparsely spotted with light to dark brown, so the scorpion looks pale and striped to unaided eye. Trichobothrial pattern A: femur with 10 trichobothria, patella without ventral trichobothria. Sternum type 1: narrowly pentagonal, with a posterior depression that does not bisect the posterior edge. Leg tarsomere II ventrally with dense and irregular cover of thin setae…………………..…….. ( Buthidae )………... 2

2.- Pedipalp fingers dark brown to black, conspicuously darker than hand. Trichobothrial pattern A-β (angle of femoral trichobothria d 1 -d 3 -d 4 opens towards internal surface). Pedipalp fingers with 5–6 principal rows of denticles, the basalmost much longer and extended over the basal half of the finger; supernumerary denticles absent. Telson with subaculear tubercle very large, sharp and triangular ……………………. Isometrus maculatus - Pedipalp fingers yellow, same-colored as, or lighter than hand. Trichobothrial pattern A-α (angle of femoral trichobothria d 1 -d 3 -d 4 opens towards external surface). Pedipalp fingers with 7–8 principal rows of denticles, all subequal and evenly distributed along the finger; supernumerary denticles flanking all principal rows of denticles internally and externally. Telson with subaculear tubercle obsolete to absent ………..…….…........ ………………………………. Centruroides barbudensis

Figures

Figure 6: Adult male Oiclus purvesii from Sint Eustatius, dorsal and ventral views.

Figure 7: Adult female Oiclus purvesii from Sint Eustatius, dorsal and ventral views.

Figure 8: Live scorpions from Sint Eustatius, in their natural habitat: (a) adult male Centruroides barbudensis; (b) adult female Centruroides barbudensis; (c) adult female Oiclus purvesii; (d) juvenile Oiclus purvesii. Photos courtesy Alejandro J. Sánchez.