Magulla obesa Simon 1892
Creators: name: Indicatti, Rafael P.
name: Lucas, Sylvia M.
name: Guadanucci, José P. L.
name: Yamamoto, Flávio U.
Publisher: name: Zenodo
Year: 2008
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Araneae
Theraphosidae
Magulla
Magulla obesa

description: Magulla obesa Simon 1892
(Figs 1; 2 A–E; 4 A–C; 5 A–I; 6 A–B; 7H, J; 8)
Magulla obesa Simon 1892a: 276; Simon 1892b: 137; Mello-Leitão 1923: 136; Bücherl 1949: 263; Gerschman de Pikelin & Schiapelli 1973: 75, figs 14–15.
Cyclosternum obesum: Raven 1985: 155; Platnick 2008.
Type material: Holotype female, Teresópolis, Rio de Janeiro, Brazil, MNHN 1041, examined.
Additional material examined: BRAZIL. Rio de Janeiro: Teresópolis, (Parque Nacional da Serra dos Órgãos, 22º27`S, 42º59`W) 1 female, 18–22.VIII.2001, Equipe Biota leg. (IBSP 12713); 1 male, 11– 12.III.2005, D.R. Pedroso & V.G.D. Orrico leg. (MNRJ 14996); 1 female, 19.III.1962, A.L. Peracchi, E. Izecksohn, I. Campos & C.P. Nena leg. (MNRJ 13254); 1 female, Petrópolis, 22°30'S, 43°11'W, (Fazenda Ranchinho da Roça), 15–16.VIII.2001, Equipe Biota leg. (IBSP 12714); 1 male, São Pedro da Aldeia, 22°51'S, 42°6'W, 03.VII.1968, S. Machado leg. (IBSP 4685); São Paulo: Jaboticabal, 21°16'S, 48°19'W, 2 males and 1 female, 2006, F.J. Cividanes leg. (IBSP 13025; IBSP 13027; FCE-MY 733); 1 male, Caconde, 21°33'S, 46°37'W, 13.X.2001, R. Bertani leg. (IBSP 9545); São Paulo, 23°31'S, 46°37'W, 1 female, X.1999 (MCN 43294); 1 male, (Centro Tecnológico da Marinha, Universidade de São Paulo - USP), 19.XII.2003, C. Braga leg. (IBSP 13016); 1 male, (Parque Estadual do Jaraguá), 20.II.2002, R.P. Indicatti leg. (IBSP 10339); 1 male, Mairiporã, 23°19'S, 46°34'W (IBSP 12948); Jundiaí, (Estação Ecológica Serra do Japi, 23º13`S, 46º56`W), 1 male, X.2002, A.D. Brescovit et. al. leg. (IBSP 12680); 2 males, 15.VIII.2002 (MCN 43293, MCTP 19543); 1 male, Itupeva, 23°8'S, 47°4'W, 29.V.00, I.S. Montesso leg. (IBSP 8367); 1 male, Vinhedo, 23°1'S, 46°58'W, 27.VII.1977, F. Alberti leg. (IBSP 4273); 1 male, Louveira, 23°4'S, 46°58'W, 14.VI.1988, A.C. Silvino leg. (IBSP 12701); 1 male, Jarinu, 23°6'S, 46°43'W, E. Muscat leg. (IBSP 10784); Cotia, 23°37'S, 46°55'W, 1 male (IBSP 8910); 1 male, 28.V.1990, R.J. da Cunha leg. (IBSP 12705); 1 male, Pinhalzinho, 22°46'S, 46°36'W (IBSP 8913); 1 female, Tatuí, 23°21'S, 47°51'W, 08.XII.2005, V. Russo leg. (IBSP 12951); 1 female, Angatuba, (Estação Ecológica de Angatuba, 23º24`S, 48º21`W), 11–16.XI.2002, Equipe Biota leg. (IBSP 13038); Itú, 23°16'S, 47°19'W, 2 males, 30.IX.2003, Centro de Animais Peçonhentos Renê D’ávila leg. (IBSP 12704); 09.IX.1993 (MZSP 27810); 1 male, Ribeirão Grande, 22°48'S, 45°27'W, III.2004, F.S. de Oliveira leg. (IBSP 12703); 1 male, Peruíbe, (Guaraúzinho, Estação Ecológica Juréia-Itatins, 24°18'S – 24°32'S, 47°00'– 47°30'W), 23.II.1997, O.A.V. Marques leg. (IBSP 12702); Paraná: 1 female, Porto Amazonas, (Caiacanga), 25°32'S, 49°53'W, IV.1954, S.S. Silva leg. (IBSP 9732).
Common name: Mickey spider (Figs 1, 2B, E).
Diagnosis: Males of M. obesa differ from those of M. brescoviti n. sp. and M. buecherli n. sp. by the palpal bulb having less developed keels and presenting a ventral curvature along the embolus (Fig. 2 A, C); females of M. obesa differ from those of M. brescoviti n. sp. by the long seminal receptacle with the apical region less dilated (Fig. 4 A–C).
Description: Male (IBSP 4685). Color in ethanol: carapace reddish-brown (Fig. 5 A), legs brown. Abdomen yellowish-brown, urticating hair patch triangular, dark-brown with light reddish setae (Fig. 5B). In life, carapace reddish-brown, abdomen and legs dark-brown. Total length 13. Carapace 7.20 long, 6.90 wide. Clypeus 0.24. Diameter of AME 0.36, ALE 0.34, PLE 0.30, PME 0.18. Cheliceral furrow with 10 teeth, with 22–23 basal smaller teeth. Labium 0.75 long, 1.30 wide, with seven cuspules. Each endite with ca. 90 cuspules. Sternum 2.85 long, 3.00 wide. Posterior sigilla twice size of anterior pair. Measurements: palp: femur 3.60, patella 2.20, tibia 2.70, cymbium 1.30, total 9.80. Legs: I: femur 5.50, patella 3.60, tibia 3.70, metatarsus 2.90, tarsus 1.95, total 17.65; II: 5.00, 3.20, 3.10, 2.90, 2.00, 16.20; III: 4.20, 2.50, 2.70, 3.60, 2.05, 12.05; IV: 5.40, 2.90, 3.70, 5.70, 2.50, 20.02. Spines: none on palp. Legs: I: tibia v1 ap, metatarsus v1 ap; II: tibia v2 ap, metatarsus v1 ap; III: tibia d0-1p-0, v1 p (ap), metatarsus d0-1p-2, v0-2-0-3ap; IV: tibia d0-2-0, metatarsus d1r-1r-2-1r-1r-1p, v0-1r-1r-1p-2r-4ap. PLS: basal, median and apical segments 0.85, 0.60, 1.00 long, respectively. Palpal bulb piriform with long embolus (ca. 3/5 of bulb length), bearing two prolateral keels weakly developed (ca. 2/5 of embolus apical length) (Fig. 2A).
Female. (IBSP 12713). Color as in male (Figs 1, 5 D–E). Total length 24. Carapace 10.80 long, 10.40 wide. Clypeus 0.52. Diameter of AME 0.34, ALE 0.36, PLE 0.35, PME 0.28. Cheliceral furrow with 17 teeth, with 23 basal smaller teeth. Labium 1.05 long, 2.00 wide, with 16 cuspules. Endites with ca. 130 cuspules. Sternum 4.40 long, 4.90 wide. Posterior sigilla three times size of anterior pair. Measurements: palp: femur 5.50, patella 3.90, tibia 3.40, tarsus 2.90, total 15.70. Legs: I: femur 6.80, patella 5.00, tibia 4.50, metatarsus 3.00, tarsus 2.10, total 21.40; II: 5.90, 4.60, 3.70, 3.00, 2.10, 19.30; III: 5.50, 3.60, 3.30, 4.00, 2.35, 10.75; IV: 6.70, 4.10, 4.60, 6.20, 2.60, 24.20. Spines: palp: tibia v1 ap. Legs: I: metatarsus 1ap; II: metatarsus v1 ap; III: tibia 1p (ap), metatarsus d0-1p-2, v0-1p-3ap; IV: tibia v2 ap, metatarsus d1r-1r-1r-1r-1r, v0-0-2-2r-3ap, p0-0- 0-1. Trichobothria: two asymmetric filiform rows not curved and not separated by setae on anterior 2/3 of metatarsi I (n=16) and one filiform row on anterior half of metatarsi II (n=20). Scopula of tarsi IV with very wide division for length, scopula restricted to both lateral sides; metatarsi: I apical half occupied, II apical 2/5 occupied, III apical 1/4 occupied, IV without scopula. PLS: basal, median and apical segments 1.45, 1.10, 1.25 long, respectively.
Variation: Males (n=20): total length 9.80–18.20. Carapace 4.90–9.10. Cuspules on labium 1–17, cuspules on endites 82–115. Females (n=8): total length 12.50–23.70. Carapace 5.00–11.20. Cuspules on labium 5–17, cuspules on endites 70–130. The shape of the urticating hair patch varies throughout the spider's life, being small and rounded in juveniles and triangular in adults. In some adult males, the patch may be rounded.
Note: Simon (1892) diagnosed female of Magulla as having anterior metatarsi shorter than tarsi. Gerschman de Pikelin & Schiapelli (1973) also used such feature as diagnostic. However, we observed that the metatarsi are shorter than the tarsi only if measured ventrally. When the dorsal surface is used to measure the segments, tarsi are longer than metatarsi.
Natural History: Spiders of this species can be found under rocks and fallen trunks in high altitudes (900–2000m) of the Atlantic Forest (Fig. 6 A–B), as well as in lowlands (0–900m) in the country side and coastal region of Rio de Janeiro and São Paulo states and in the countryside of Paraná state. A female of M. obesa in captivity was observed digging its burrow with palps and legs I–II, as occurs in some other Theraphosidae (Pérez-Miles et al. 1993) and most other mygalomorphs (Coyle 1995; Bond & Coyle 1995; Goloboff 1995; Lucas et al. 2005). These spiders are not easily disturbed to the point they flick their urticating hairs.
Distribution: Known from Southeastern and Southern Brazil, states of Rio de Janeiro, São Paulo and Paraná (Fig. 8).
description: Published as part of Indicatti, Rafael P., Lucas, Sylvia M., Guadanucci, José P. L. & Yamamoto, Flávio U., 2008, Revalidation and revision of the genus Magulla Simon 1892 (Araneae, Mygalomorphae, Theraphosidae), pp. 21-36 in Zootaxa 1814 on pages 26-27, DOI: 10.5281/zenodo.182866