Gonycranaus pluto, Bragagnolo & Hara & Pinto-Da-Rocha, 2015

Bragagnolo, Cibele, Hara, Marcos R. & Pinto-Da-Rocha, Ricardo, 2015, A new family of Gonyleptoidea from South America (Opiliones, Laniatores), Zoological Journal of the Linnean Society 173 (2), pp. 296-319 : 316-317

GONYCRANAUS PLUTO SP. NOV.

( FIGS 6 ; 9D–F )

Etymology

After Pluto, one of the six Olympian gods and the god of the underworld previously named as Hades. In reference to the fact its species is restricted to cave environments.

Type material

BRAZIL. Minas Gerais: Morro do Pilar , Gruta MP 01B, 881337mN/667890mE SAD′69, 03–06.X.2011, Bessi et al. leg, ♂ holotype ( MZSP 57196 ) . Paratypes : BRAZIL. Minas Gerais: Morro do Pilar , Gruta MP 01B, 7881337mN/667890mE SAD′69, 28.II.2012, Bessi et al. leg., 1 ♀ ( MZSP 57197 ) ; idem, 1 ♀ ( MZSP 57192 ) ; idem, 1 ♀ ( MZSP 57242 ) , idem, 1 ♂ ( MZSP 57243 ) ; idem, 1 ♀ ( MZSP 57244 ) ; idem, 1 ♂ ( MZSP 57245 ) ; idem, 1 ♀ ( MZSP 57246 ) ; idem, 03–06.X.2011, R. Bessi et al. leg., 1 ♀ ( MZSP 57247 ) ; idem, 1 ♂ ( MZSP 57248 ) .

Diagnosis

Gonycranaus pluto is very similar to G. androgynus and differs by legs I–IV elongated, body coloration lightened, and absence of ventral process of penis.

Description

Male (holotype): Dorsum ( Fig. 6A, B ): Measurements: DSL 3.6; DSW 2.95; LI 15.2; LII 26.3; LIII 21.0; LIV 28.9. Leg IV/body length ratio: 8.02. Anterior margin of carapace with frontal hump covered by tubercles. Ocularium far from anterior margin of carapace, tuberculate, unarmed. Scutal area I entire; scutal areas I–IV unarmed. Scutal groove II complete. Dorsal scutum outline type alpha, entirely tuberculate. One ozopore (anterior opening), covered by integumentary dome with slit-like opening obstructed by prolateral apophysis of coxa II (on lateral view). Posterior margin of dorsal scutum densely tuberculate, unarmed. Free tergites I– III each with a row of tubercles. Anal operculum tuberculate, unarmed.

Venter. Coxa I–IV, genital and free sternites tuberculate.

Chelicera. Enlarged. Segment I completely covered with pointed tubercles on bulla, segment II very enlarged with six teeth, segment III with six teeth (the basalmost largest).

Pedipalp ( Fig. 6E, F ). Coxa with one ventral pointed apophysis. Trochanter inflated, dorsally with four or five pointed tubercles, ventrally with one tubercle and one pointed apophysis. Femur dorsally with a median row of nine or ten pointed tubercles, one apical prolateral row of six tubercles, one apical retrolateral row of between three and five tubercles, and one prolateral apical pointed apophysis. Ventrally with a row of nine or ten high, enlarged pointed tubercles, the basalmost largest. Patella dorsolaterally with scattered tubercles, ventrally smooth. Tibia dorsolaterally with scattered tubercles; tibial setation, mesal IiiIiIi, ectal IiIiIi. Tarsus dorsolaterally smooth; tarsal setation, mesal iIiiIii, ectal iIiIiii. Tarsal claw as long as tarsus length.

Legs ( Fig. 6C, D ). Coxa I with one prolateral and one retrolateral apophyses (retrolateral largest); coxa II and III with one prolateral and one retrolateral apophyses; coxa IV tuberculate, with one short bifid prolateral apical apophysis and one small apical retrolateral pointed tubercle (visible ventrally). Trochanters – tibiae I–IV tuberculate; trochanter IV with one retrolateral apical enlarged tubercle. Femur III densely tuberculate, ventrally with one retrolateral and one prolateral row of tubercles increasing in size apically. Femur IV straight and densely tuberculate, with one prodorsal and one retrodorsal apical enlarged, pointed tubercles; a row of retrolateral spiniform tubercles (increasing in size apically); ventrally with one retrolateral and one prolateral row of tubercles increasing in size apically, with one apical pointed apophysis. Patella III ventrally with one median enlarged tubercle and one apical pointed apophysis. Patella IV with four dorsoapical enlarged, pointed tubercles and ventrally with one apical pointed apophysis. Tibia IV with a retroventral row of tubercles increasing in size apically. Basitarsus I not inflated. Tarsal counts: 9(3), 18(3), 7, and 8.

Penis ( Fig. 9D–F ). Ventral plate distal margin straight, its width a quarter of the basal portion, basally as wide as truncus apex; with three subapical pairs of unbranched setae, three basal pairs of unbranched long setae (longest set). Truncus apex slightly inflated. Glans sac subcylindrical. Stylus short, slightly curved. Without ventral process.

Coloration. Background colour yellowish brown.

Female (paratype MZSP 57197; Fig. 6G, H ): Measurements: DSL 3.30; DSW 2.95; LI 16.6; LII 27.0; LIII 22.8; LIV 28.5. Leg IV/body length ratio: 8.6. Pedipalp: tibial setation, mesal IIiIi, ectal IiIiIi; tarsal setation, mesal iIiiI, ectal iIiIii. Tarsal counts: 8(3), 19(3), 7, and 8.

Variation in males (N = 3): Measurements: DSL 3.3– 3.5; DSW 2.80–2.85; LI 17.1–19.9; LII 30.5–31.0; LIII 21.7–22.3; LIV 28.9–29.4. Leg IV/body length ratio: 8.3–8.9. Pedipalp: femur dorsally with a median row of between nine and 11 pointed tubercles; tibial setation, mesal IiIiiI/IiIiIi, ectal IiIiIi/IiIIi; tarsal setation, mesal iIiiIii, ectal iIiIi. Tarsal counts: 9–10(3), 18–20(3), 7, and 8.

Variation in females (N = 2): Measurements: DSL 2.9– 3.0; DSW 2.6–2.65; LI 16.0–16.1; LII 27.0–33.5; LIII 21.5– 21.9; LIV 28.5–29.95. Leg IV/body length ratio: 10.1. Pedipalp: tibial setation, mesal IiiIiI/IiIiIi, ectal IiIiIi; tarsal setation, mesal iIiiIii, ectal iIiIi. Tarsal segmentation: 8–9(3), 19(3), 7, and 8.

Notes. Gonycranaus pluto presents elongate appendages and depigmentation of the body and legs. It was only collected from dark areas of just one limestone cave (from the entrance to the deepest regions), despite thorough collecting efforts outside the entrance. These features are typical characteristics of Neotropical obligate cave-dwelling harvestmen (see for example Pérez-Gonzalez & Kury, 2002; Hara & Pinto-da-Rocha, 2008).

Figures

Figure 6. Gonycranaus pluto sp. nov. A–F, male holotype: A, habitus, dorsal view; B, habitus, right lateral view; C, right trochanter–patella IV, dorsal view; D, right trochanter–patella IV, ventral view; E, right pedipalp, retrolateral view; F, right pedipalp, prolateral view. G, H, female paratype (MZSP 57197): G, habitus, dorsal view; H, habitus, right lateral view. C and D at same scale; E and F at same scale. Scale bars: 1 mm.

Figure 9. Distal part of penis. A–C, Gonycranaus androgynus sp. nov. (holotype): A, dorsal view; B, left lateral view; C, ventral view. D–F, Gonycranaus pluto sp. nov. (holotype): D, dorsal view; E, left lateral view; F, ventral view. Scale bars: 0.1 mm.