Eusarcus capixaba, Júnior & Ázara & Ferreira, 2021

Júnior, Gilson Argolo dos Santos, Ázara, Ludson Neves de & Ferreira, Rodrigo Lopes, 2021, Three new species of Eusarcus Perty, 1833 (Opiliones, Gonyleptidae) from Brazilian caves, European Journal of Taxonomy 740 (1), pp. 36-54 : 38-42

Eusarcus capixaba sp. nov.

urn:lsid:zoobank.org:act:E67BD462-5F7E-49D2-AB50-1DE3202F947A

Figs 1–3 , 11

Diagnosis

Eusarcus capixaba sp. nov. can be distinguished from all species of the genus by having a pair of high (twice as tall and wide as surrounding granules), round tubercles on scutal area I. Eusarcus capixaba sp. nov. resembles E. aduncus , E. armatus Perty, 1833 , E. cavernicola , E. dandara Saraiva & DaSilva, 2016 , E. fulvus Soares & Soares, 1946 , E. mirabilis Pinto-da-Rocha & Hara, 2010 and E. oxyacanthus Koch, 1839 by the presence of one oblique, proapical, acute and conical apophysis on trochanter IV but can be distinguished by the following characters: low ocularium height, proapical apophysis of coxa IV shorter than trochanter IV length and trochanter IV with dorsally-curved and sinuous promedian apophysis.

Etymology

The specific epithet ʻ capixaba ʼ is derived from the TUpi langUage, meaning ʻfield landʼ, in allUsion to corn and mandioca fields cUltivated by local Indian tribes. It also refers to the natives of the Brazilian state of Espírito Santo.

Material examined

Holotype BRAZIL • ♂; Espírito Santo State, Ecoporanga MUnicipality, Lapa do Sítio Paraíso cave ; 18°27′49.5″ S, 40°49′52.2″ W; 22 JUl. 2004; R.L. Ferreira et al. leg.; ISLA 12966 (destroyed).

Paratype BRAZIL • 1 ♂; same collection data as for holotype; ISLA 66189 (destroyed).

Description

Male (holotype, ISLA 12966)

MEASUREMENTS. DSL 4.32, DSW 3.28, femur I 2.26, II 5.69, III 4.18, IV 5.24.

DORSUM ( Fig. 1A, C ). Acuminate PAM; median paracheliceral projection similar in size to PAM. Low ocularium with two low tubercles (half ocularium height). Carapace with scattered granules. Scutal areas I–IV with scattered tubercles; scutal area I with antero-lateral pair of tubercles (higher than the others of the other areas) with black inner pigmentation; scutal area III with median oblique spine that is bifurcate apically and longitudinally. Posterior margin of dorsal scutum with scattered granules. Free tergites I–III with a defined row of granUles. Anal opercUlUm with scattered granUles.

VENTER ( FIG. 1B ). Coxa I with irregular row of setiferous tubercles, coxae II–IV densely and irregularly granulated.

CHELICERAE. Segment I with three basal and one apical tubercle.

PEDIPALPS. Trochanter inflated with sparse tUbercles dorsally. FemUr with one mesal apical setiferoUs tubercle.

LEGS ( Fig. 2 ). Coxae I–IV with scattered granules; coxa IV with one oblique proapical apophysis, which is conical, short and curved posteriorly. Trochanters I–IV with scattered tubercles; trochanter IV with one promedian apophysis, which is conical, slightly curved dorsally and with a sub-basal granule. Femur III with retroventral row of about three main pointed tubercles on apical portion; femur IV slightly sinuous, with small PDS and RDS, with proventral and retroventral rows of tubercles similar to granUles. Patellae, tibiae and metatarsi I–IV granUlated withoUt defined armatUre.

COLOURATION (in alcohol) ( Figs 1–2 ). Background colour of body and appendages Deep Orange (51), pair of tubercles on scutal area I with black inner pigmentation, segments Brilliant Orange (49).

PENIS ( Fig. 3 ). Ventral plate with substraight lateral margins; distal margin slightly concave; ventral surface entirely covered with type T1 microsetae; with 3 pairs of lateral-distal MS C1–C3, one pair of A1 and B1 and one pair of minUte D1 and E1. StylUs smooth, ventrally tilted, with basis flattened, median region swollen and with an internal depression forming a distinct groove. Ventral process spatula-shaped, dorsally and basally tilted.

Female

Unknown.

Intraspecific variation

Males (n = 2): DSL 4.32–4.80; DSW 3.28–3.46; femur I 2.26–2.72; II 5.69–6.05; III 4.18–3.12; IV 5.24– 5.78. Spine of scUtal area III with apex single or bifid.

Geographical distribution

Known only from the type locality ( Fig. 11 ).

Ecological remarks

Caverna do Sítio Paraíso is a small granite cave at the base of a massive granitic outcrop located in the municipality of Ecoporanga (Espírito Santo State, southeastern Brazil). The cave corresponds to a straight-line conduit with 12 meters of horizontal projection. This conduit is quite narrow (around 1 meter), although it is quite high. At the time of collection, the cave was inhabited by a small colony of guano producing carnivorous bats [ Chrotopterus auritus (Peters, 1856) ]. The guano pile, apparently the only detectable organic resource within the cave, was located in the deepest portion of the cave. The specimen of Eusarcus capixaba sp. nov. was found freely walking around the faecal pellets that formed the guano pile. It is important to mention that one of the authors (R.L. Ferreira), who collected the specimen, contracted histoplasmosis (a disease caused by the fungus Histoplasma capsulatum Darling ) during the visit to this cave, and so caution should be taken during any future surveys. Since no sampling was conducted outside the cave, it is impossible to determine the habitat preference of this species. The landscape surrounding the cave is partially altered, although a forest occurs around the granitic outcrop. The external vegetation is of the Atlantic Forest domain, and the region presents an Aw5 climate according to the Köppen classification system, with an average annUal precipitation of aroUnd 1082 mm and an average annual temperature of 24.7ºC.

Figures

Fig. 1. Eusarcus capixaba sp. nov., ♂, holotype (ISLA 12966), habitUs. A. Dorsal view. B. Ventral view. C. Right lateral view. Scale bars: A–B = 1 mm; C = 0.5 mm.

Fig. 2. Eusarcus capixaba sp. nov., ♂, holotype (ISLA 12966). A–B. Femur IV, dorsal and ventral view, respectively. C–D. Patella and tibia IV, dorsal and ventral view, respectively. E–F. Femur III, dorsal and ventral view, respectively. G–H. Trochanter IV, dorsal and ventral view, respectively. Scale bars: A–F = 0.5 mm; G–H = 0.2 mm.

Fig. 3. Eusarcus capixaba sp. nov., ♂, holotype (ISLA 12966), distal part of penis. A. Dorsal view. B. Ventral view. C. Right lateral view. D. Left lateral view. Macrosetae highlighted in different coloUrs: light blUe = MS A; pUrple = MS B; pink = MS C; yellow = MS D; green = MS E. Scale bars = 50 μm.

Fig. 11. Known distribution of Eusarcus capixaba sp. nov., Eusarcus marmoreus sp. nov. and Eusarcus xambioa sp. nov. in Brazil.