Ischnotelson guanambiensis (Lenarducci, Pinto-da-Rocha and Lucas, 2005), comb. nov.

Figures 1 B, 2C, 9A, 10A, 12E, 15A, 19A, 21C, 22C, 23O–R, 36A, B, 37A, C, 38A, 39

Rhopalurus guanambiensis: Lenarducci et al., 2005: 1, 2, 7, tables 1, 2, figs. 1–11; Lourenço, 2008: 3; Prendini et al., 2009: 222; Brazil and Porto, 2010: 50; Porto et al., 2010: 293, 295, table 1; Lourenço, 2014: 69; Ubinski et al., 2016: 122.

TYPE MATERIAL: Rhopalurus guanambiensis: Holotype ♂ (IBSP-SC 3404), 3 ♂ paratypes (IBSP-SC 3406-3407, MZSP-22590), paratype ♀ (IBSP-SC 3405), BRAZIL: Bahía: Guanambí, 14°11′15″S 42°48′45″W, 1985, V.F. Neves.

DIAGNOSIS: Ischnotelson guanambiensis differs from its sister species, I. peruassu, sp. nov., as follows. Ischnotelson guanambiensis is smaller, varying from 35–45 mm in total length, than I. peruassu, which varies from 48–59 mm. Metasomal segments IV, V, and telson are darker in I. guanambiensis than in I. peruassu . The pedipalp chela fingers are noticeably darker than the chela manus in I. guanambiensis, but similar in color to the manus in I. peruassu . The pedipalps and legs are covered by fine setae in I. guanambiensis, but sparsely setose in I. peruassu . The granulation of the carapace of I. guanambiensis is coarser than that of I. peruassu, and the dorsal intercarinal surfaces of the metasoma are shagreened in I. guanambiensis, but smooth in I. peruassu . The carinae of the carapace are more pronounced in I. guanambiensis than in I. peruassu . Sternite III is elevated anteriorly in I. guanambiensis unlike in I. peruassu (fig. 10A). Finally, the sexual dimorphism of the adult male I. guanambiensis is more pronounced than that of the adult male I. peruassu: the pedipalps are more incrassate, the fixed and movable fingers of the pedipalp chela are markedly curved proximally and the posterior broadening of the metasoma is more pronounced in the former.

DISTRIBUTION: Ischnotelson guanambiensis is endemic to the Brazilian state of Bahía, and known only from the type locality, near the city of Guanambí.

ECOLOGY: The type and only known locality is situated on the ecotone of Brazilian caatinga and cerrado (fig. 2C). Personally collected specimens were found at night with UV light detection. The habitat and habitus are consistent with the lapidicolous ecomorphotype (Prendini, 2001b).

MATERIAL EXAMINED: BRAZIL: Bahía: Município Ceraíma: Aeroporto de Guanambí, Guanambí, 14°13′0 0″S 42°46′60″W, 15.viii.2007, H.Y. Yamaguti et al., 1 ♀ (MZSP 70872), 17. xii.2007, H.Y. Yamaguti et al., 1 subad. ♀ (MZSP 30864/AMCC [LP 9669]), 1 subad. ♂ (MZSP 30865/AMCC [LP 9670]), 21.i.2009, H.Y. Yamaguti et al., 1 ♂ (MZSP 70873) .