Idiops piluso Ferretti, Nime and Mattoni, 2017

Ferretti, N., Nime, M. & Mattoni, C., 2017, Three new Idiops (Mygalomorphae: Idiopidae) from Argentina and redescription of the male of I. hirsutipedis Mello-Leitão, 1941, Journal of Natural History (J. Nat. Hist.) 51 (17 - 18), pp. 975-994 : 986-990

Idiops piluso Ferretti, Nime and Mattoni sp. nov.

( Figures 9–11 , 13 )

Type material

Holotype male. Argentina, Córdoba, Pocho, Parque Natural Provincial y Reserva Forestal Natural Chancaní , (31°21′0.35″ S – 65°29′20.89″ W), 12–19 January 2010, pitfall trap, M. Nime and M. G. Farías col. (LBRE-Ar) . Paratype female: Argentina, Córdoba, Bosque Alegre, Santa Rosa small farm, 9 October 1981, P . Goloboff col . (MACN-Ar36721).

Additional material examined

Argentina, Córdoba, Pocho, Parque Natural Provincial y Reserva Forestal Natural Chancaní (31°21′11.45″ S – 65°29′2.47″ W), 13–20 January 2010, pitfall trap, M . Nime and M . G. Farías col ., 1♂ ( LZI438 ); Argentina, Córdoba, Bosque Alegre (31°35′32.6″ S – 64° 31′38.2″ W), 27 September – 1 October 1981, P . Goloboff col ., 2 ♀, 1 juvenile (MACN- Ar 7425); Argentina, Córdoba, Chancaní (31°21′11.45″ S – 65°29′2.47″ W), 16 April 1987, P . Goloboff col ., 1 juvenile (MACN-Ar36722).

Diagnosis

Males of I. piluso sp. nov. resemble those of I. hirsutipedis in the presence of labial and maxillary cuspules ( Figure 9 (b)) and fovea almost straight ( Figure 9 (a)), but can be easily separated by the straight metatarsus I and absence of an apical prolateral process. They can be distinguished from all other Argentinean species by the palpal tibia more incrassate and shorter, being wider than half of its length (less than or almost as wide as half its length in other species), retrolateral spines concentrated on the basal and apical portion of the depression, where apical spines are very long ( Figure 9 (d)). Also, it can be distinguished from I. clarus and I. minguito sp. nov. by the shorter spine on apical branch of tibial apophysis and by the larger spine on the basal branch ( Figure 9 (e)), palpal bulb with slightly developed apical expansion and tip of the embolus without dorsal tooth ( Figure 10 (a–c)). The female differs from that of the other species by the spermathecae with oval receptacles almost equal the width of the ducts, which are straight and shorter, and a slightly sclerotised basal area ( Figure 11 (d)).

Etymology

The species is a name in apposition of ‘Capitán Piluso’, a famous TV character interpreted by the Argentine actor Alberto Olmedo (1933–1988) during the 1960s. The character was a comic man dressed as a sailor and was an idol for children.

Description

Male holotype (MACN-Ar36720). Colouration (in alcohol): carapace, chelicerae and legs uniformly light brown ( Figure 9 (a)), abdomen uniformly grayish without dorsal spots. Total length 7.80; carapace 3.81 long, 3.19 wide. Carapace oval with granules throughout ( Figure 9 (a)); fovea deep, slightly procurved, 0.75 wide. Ocular group 0.95 long, 1.01 wide. ALE situated far in advance of the rest ( Figure 9 (c)). Posterior row slightly procurved. Distance between AME and ALE 0.12. Eye sizes and interdistances: AME 0.19, PME 0.14, ALE 0.27, PLE 0.30, AME–AME 0.16, PLE–PME 0.11, PME–PME 0.28. Labium 0.41 long, 0.71 wide, with 2 cuspules (although holes indicate 5 cuspules), labiosternal groove shallow. Maxillae with 8/9 (right/left) cuspules. Chelicerae with 6 promarginal teeth and 8 retromarginal teeth, rastellum conspicuous on a distinct process. Sternum elongated; 2.23 long, 1.97 wide with thin long setae on entire surface ( Figure 9 (b)). Leg formula 4-1-2-3, morphometry (femur, patella, tibia, metatarsus, tarsus, total): I: 4.05, 1.06, 2.98, 3.04, 1.85, 12.98. II: 4, 1.32, 2.37, 2.73, 1.57, 11.99. III: 3.06, 1.51, 1.88, 2.63, 1.81, 10.89. IV: 4.6, 1.73, 3.55, 3.84, 1.87, 15.59. Palp: 1.1, 0.72, 2.19, –, 0.82, 4.83. Spines: Palp: femur 0, patella 0, tibia 23r, tarsus 0. I: femur 1-1-1-1d, patella 1v, tibia 1-1v, metatarsus 1-1r, 1-1-1-1p, tarsus 1-1-1-3r, 1-1-1- 1p. II: femur 1-1-1d, patella 0, tibia 1-1-2v, metatarsus 1-1-1-1r, 2v, 2p, tarsus 1-1-1-1r, 1-1-1- 1p. III: femur 1-2-1d, patella 1d, 2r, 1-1-1-1-1-2-2-3p, tibia 1-1d, 2-2v, 1-1-1-1-1p, 1-1-1r, metatarsus 2-2-3v, 1-1-2r, 1-1-1p, 1-2-2d, tarsus 1-1-1-1-1p, 2-1-1r. IV: femur 1-1-1d, patella 9-1-0p, tibia 1-1-2v, 1-1-1d, metatarsus 1r, 2p, 1-1-1-2v, tarsus 1-1-1p, 1-1-1r. Scopulae: legs I 1/2 scopulated divided by conical thick setae, legs II–IV with scopulae complete and entire. Tibia of leg I with double tibial apophysis; superior branch bigger than inferior with a long spine, the inferior branch has an apical big stout spine ( Figure 9 (e)). Metatarsus I straight. Palpal tibia very incrassate (wider than half of its length) with retrolateral concavity, crescent-shaped band of about 23 spines along the entire retrolateral side of concavity (larger spines are located apical and basal of concavity) ( Figure 9 (d)). Palp with a very long embolus broad at base abruptly tapering at distal end with small apical expansion ( Figure 10 (a–c)).

Female Paratype (MACN-Ar36721). Colouration (in alcohol): carapace, chelicerae and legs uniformly light brown ( Figure 11 (a)), abdomen grayish. Total length 9.72; carapace 3.80 long, 4.16 wide. Carapace oval; fovea deep, strongly procurved, 1.11 wide. Ocular group 1.19 long, 0.96 wide. ALE situated far in advance of the rest ( Figure 11 (c)). Posterior row slightly procurved. Distance between AME and ALE 0.20. Eye sizes and interdistances: AME 0.17, PME 0.16, ALE 0.26, PLE 0.31, AME–AME 0.13, PLE–PME 0.12, PME–PME 0.21. Labium 0.65 long, 0.90 wide, with 2 cuspules, labiosternal groove shallow. Maxillae with 25/27 (right/left) cuspules. Chelicerae with 7 promarginal teeth and 9 retromarginal teeth, rastellum conspicuous on a distinct process. Sternum elongated; 2.64 long, 2.55 wide with thin setae on entire surface ( Figure 11 (b)). Leg formula 4-1-2-3, morphometry (femur, patella, tibia, metatarsus, tarsus, total): I: 2.2, 1.42, 1.47, 1.45, 0.8, 7.34. II: 2.24, 1.4, 1.22, 1.17, 0.85, 6.88. III: 1.82, 1.33, 1.07, 1.26, 1.12, 6.6. IV: 3.22, 1.6, 2.24, 2, 1.51, 10.57. Palp: 2.21, 1.14, 1.58, –, 1.84, 6.77. Spines: Palp: femur 2p, patella 1v, tibia 3-5-9p, 2-6-9r, tarsus 7-7-5r, 10-8- 8p. I: femur 0, patella 0, tibia 4-3-9r, 1-4-5p, metatarsus 8-7-4r, 6-7-6p, tarsus 3-3-4r, 2-4- 3p. II: femur 0, patella 0, tibia 0-2-4p, 1-1v, metatarsus 1-4-2r, 4-8-8p, tarsus 1-3-1r, 3-2- 4p. III: femur 0, patella 2d, 3-4-7p, tibia 2-2-5p, 1-1-1-1r, metatarsus 3-2-1-1r, 4-2-3p, 1-2-2v, tarsus 0-3-3v, 1- 1p. IV: femur 1d, patella 20-4-0p, tibia 1-1-1v, metatarsus 1-1r, 1p, 1-1-1-2v, tarsus 3-2-1-2v, 1r, 1-3-2- 2p. Scopulae: absent on legs I–IV. Tibia of leg III normal. Spermathecae with globular apical receptacles and straight and short ducts ( Figure 11 (d)).

Natural history

This species was collected in the Chancaní Reserve, which is located in the southernmost portion of the Arid Chaco ecoregion (NT0701 in Olson et al. 2001) in Córdoba province, Argentina. Vegetation in the reserve comprises dry xerophyllous woodland. The canopy is discontinuous and ~ 15 m high, dominated by the trees Aspidosperma quebracho-blanco and Prosopis flexuosa . The shrub stratum (~ 4 m high) is thorny, dense, and almost continuous, dominated by Larrea divaricata, Mymozyganthus carinatus, and Acacia furcatispina ( Carranza et al. 1992) .

Distribution

Known from central Córdoba province, Argentina ( Figure 13 ).

Figures

Figure 9. Idiops piluso sp. nov., holotype male (LBRE-Ar). (a) Carapace, dorsal view. (b) Labium and sternum, ventral view. (c) Eye group, dorsal view. (d) Palpal tibia, retrolateral view. (e) Leg I, prolateral view. Scale bars = 1 mm.

Figure 10. Idiops piluso sp. nov., holotype male (LBRE-Ar), left palpal bulb. (a) Prolateral. (b) Retrolateral. (c) Dorsal. Scale bar = 1 mm.

Figure 11. Idiops piluso sp. nov., paratype female (MACN-Ar36721). (a) Carapace, dorsal. (b) Labium and sternum, ventral view. (c) Eye group, dorsal view. (d) Spermathecae, dorsal view. D = duct; R = receptacle; SA = sclerotised basal area. Scale bars = 1 mm.

Figure 13. Map showing the distribution of the Idiops species treated in this work.