Loxosceles karstica Bertani, von Schimonsky & Gallao

Bertani, Rogerio, Schimonsky, Diego M. von, Gallao, Jonas E. & Bichuette, Maria E., 2018, Four new troglophilic species of Loxosceles Heinecken & Lowe, 1832: contributions to the knowledge of recluse spiders from Brazilian caves (Araneae, Sicariidae), ZooKeys 806, pp. 47-72 : 47

Loxosceles karstica Bertani, von Schimonsky & Gallao sp. n. Figs 1, 18-21, 22-27

Material examined.

Female holotype (MZUSP 74432), male paratype (MZUSP 74433), 2 female paratypes (LES 14712), 2 male and 2 female paratypes (MZUSP 74434), 3 female paratypes (MZUSP 74435), 3 male and 3 female paratypes (LES 14595), BRAZIL: Minas Gerais, Januária, Janelão Cave (15°06'S, 44°14'W) 600 m a.s.l., M.E. Bichuette, P.P. Rizzato and J.E. Gallão leg., 22.vii.2012.

Other material examined.

BRAZIL, Minas Gerais: Januária, Janelão Cave (15°06'S, 44°14'W) 600 m a.s.l., 2 immatures, M.E. Bichuette, P.P. Rizzato and J.E. Gallão leg., 22.vii.2012 (LES 14596), 1 immature, same collectors and date (LES 14713); Bahia: Carinhanha, Gruna do Cocho Cave (13°36'S, 43°46'W) 514 m a.s.l., 3 females, M.E. Bichuette, N. Hattori and J.E. Gallão leg., 02.vi.2012 (LES 14597).

Diagnosis.

Males of Loxosceles karstica sp. n. resemble those of L. ericsoni sp. n. by the palpal tibia length more than 1.4 and less than 2.0 times the cymbium length. They can be distinguished from those of L. ericsoni sp. n. by the shorter cymbium and stouter embolus (Figs 26, 27). Females of L. karstica sp. n. resemble those of L. similis , L. chapadensis , and L. niedeguidonae by the spermathecae having the sclerotized transversal plate with two long and straight receptacles. They differ from the females of the species above by the short, sclerotized transverse plate with the receptacles positioned at an angle of 45° to the inner side (Figs 20, 21). Additionally, they can be distinguished from females of L. chapadensis by the dorsal part of the bursa copulatrix medially sclerotized (Fig. 21) and from L. niedeguidonae by the non-incrassated palpal tarsus (Fig. 19).

Description.

Female holotype: Total length 8.60. Carapace 3.58 long, 3.16 wide. Eye sizes and interdistances: ALE 0.24, PME 0.21, PLE 0.24, PME-PLE 0.05, PME-ALE 0.20; clypeus 0.32. Leg formula II, I, IV, III. Legs length: leg I: femur 7.49, patella 1.18, tibia 8.10, metatarsus 7.79, tarsus 1.79, total 26.35; II: 8.29, 1.25, 9.01, 9.05, 1.74, 29.34; III: 6.39, 1.28, 6.32, 7.17, 1.53, 22.69; IV: 7.41, 1.31, 7.43, 8.42, 1.58, 26.15. Palp: femur 1.44 long, 0.24 wide; patella 0.52 long, 0.34 wide; tibia 1.02 long, 0.29 wide; tarsus 1.41 long, 0.24 wide. Labium 0.80 long, 0.58 wide. Sternum 1.90 long, 1.74 wide. Femur I 2.1 times as long, tibia I 2.2 times as long, and leg I 7.3 as long as carapace. Palpal femur 6 times longer than wide; tibia 3.5 longer than wide; tarsus not incrassate (Fig. 19). Spermathecae sclerotized transverse plate short with almost-straight receptacles positioned at an angle of 45° to the inner side (Figs 20, 21). Dorsal part of the bursa copulatrix medially sclerotized (Fig. 21). Cephalic region of carapace with some sparse, long setae (Fig. 18). Carapace with dark-brown pars cephalica and border (Fig. 18). Legs brown, covered by short, greyish setae. Palp light brown, except for reddish brown tibia and tarsus (Fig. 19). Coxae and sternum light brown. Endites and labium brown.

Male paratype: Total length 6.56. Carapace 3.06 long, 2.76 wide. Eye sizes and interdistances: ALE 0.26, PME 0.21, PLE 0.20, PME-PLE 0.04, PME-ALE 0.17; clypeus 0.32. Leg formula II, I, IV, III (inferred from male MZUSP 74434; see below). Leg lengths: leg I: missing; II: femur 9.39, patella 1.22, tibia 10.58, metatarsus 11.69, tarsus 0.92, total 33.80; III: missing; IV: 7.91. 1.24. 8.06. 9.50. 1.64. 28.35. Palp: femur 1.72 long, 0.29 wide; patella 0.51 long, 0.35 wide; tibia 0.84 long, 0.48 wide; cymbium 0.57 long, 0.44 wide. Labium 0.52 long, 0.44 wide. Sternum 1.67 long, 1.57 wide. Femur I 2.6 times as long, tibia I 3.1 times as long, and leg I 9.9 as long as carapace (inferred from male MZUSP 74434; see below). Palpal femur 5.9 times longer than wide, tibia 1.7 times longer than wide, cymbium oval (Figs 26, 27). Bulb suboval and a little smaller than cymbium. Embolus curved from its basis, approximately 1.8 times longer than bulb length in retrolateral view, without carina (Figs 23-25). Cephalic region of carapace covered by some sparse setae (Fig. 22). Entire pars cephalica dark-brown, carapace border dark-brown but slightly faded (Fig. 22). Legs, palps, endites, coxae, sternum, and labium light brown.

Remarks.

The male specimen in better condition to be chosen as paratype lacks legs I and III. For this reason, another male (MZUSP 74434), not in condition to serve as type, had legs measured as follows: leg I: femur 8.25, patella 1.16, tibia 9.88, metatarsus 10.33, tarsus 2.10, total 31.72; II: 9.89, 1.23, 11.72, 13.07, 2.02, 37.93; III: 7.49, 1.06, 7.51, metatarsus broken, tarsus missing; IV: 8.21, 1.06, 8.72, 10.24, tarsus missing. Carapace: 3.20 long, 2.94 wide.

The new species L. karstica sp. n. has genitalic characteristics shared with other species of the gaucho group distributed in the southern regions of Brazil and Paraguay, as L. gaucho , L. similis , L. adelaida , and L. variegata , which have palpal tibia that are short and incrassate in males (Figs 26, 27) and the large spermathecae transverse plate in females (Figs 20, 21). It also shares characteristics with the species of the gaucho group that are more distributed in the northern part of Brazil, as L. chapadensis and L. niedeguidonae , as they have a longer palpal tibia in males and a spermathecae transverse plate that is almost as short as in the new species but with differences in the bursa copulatrix sclerotization and the size and shape of receptacles.

Etymology.

The specific name refers to karst, a word used to define terrain with distinctive hydrology and landforms that arise from a combination of high rock solubility and well-developed porosity. Loxosceles karstica sp. n. occurs in two important karst areas of Brazil ( Peruaçu and Serra do Ramalho).