Longistylus ygapema, Indicatti, Rafael Prezzi & Lucas, Sylvia Marlene, 2005

Indicatti, Rafael Prezzi & Lucas, Sylvia Marlene, 2005, Description of a new genus of Nemesiidae (Araneae, Mygalomorphae) from the Brazilian Cerrado, Zootaxa 1088, pp. 11-16 : 12-16

Longistylus ygapema n. sp.

( Figs. 1–18 )

Types. Male Holotype from Chapada dos Guimarães, Mato Grosso, Brazil, Sept. 20, 1999, C. Strüssmann leg., deposited in IBSP 9731. Paratypes: 4 males, Cáceres, Mato Grosso, Brazil, Dec., 1997, M.E.V. Calleffo leg. (IBSP 8318); 1 male, Campus da Universidade Federal de Corumbá, Corumbá, Mato Grosso do Sul (IBSP 8322); 1 male, Brasília, Distrito Federal, Brazil, Oct. 29–31, 1999, G.G. Montigelli leg. (IBSP 8009); 1 male, Parque Nacional das Emas, Mineiros, Goiás, Brazil, Aug., 1999, P. Valdujo & C. Nogueira leg. (MZSP 24082); 1 male, Cáceres, Mato Grosso, Brazil, Dec., 1997, M.E.V. Calleffo leg. (MEPG 1188).

Other Material examined. BRAZIL. Goiás: Mineiros, Parque Nacional das Emas, 1 male, Sept. 0 5, 1997, C. Nogueira & P. Valdujo leg. ( IBSP 8319); Distrito Federal: Brasília, 1 male, Oct. 29­31, 1999, G.G. Montigelli leg. ( IBSP 8007).

Etymology. The specific name is a noun in apposition taken from the Tupi­Guarani indian language that means sword, and refers to the shape of the embolus. Diagnosis. See diagnosis of the genus.

Description. Male (holotype). Coloration pattern: Cephalothorax and legs dark yellow ( Figs. 4–5 ). Abdomen dorsally yellow with two paramedian dark stripes and ventrally yellow with dark stripe ( Figs. 6–8 ). Total length, excluding chelicerae, 15.04. Cephalothorax 7.40 long, 3.00 wide, with fovea short and procurved ( Fig. 5 ). Clypeus present narrow. Anterior eye row procurved, posterior slightly recurved. AME smaller than ALE, ALE larger than PLE and PME smaller than PLE. Overall shape of eye group trapezoidal, wider than long in ratio ( Fig. 5 ). Basal segment of chelicerae with eight teeth in a row and rastellum with very strong setae. Intercheliceral tumescence small, pale covered by few hairs. Labium 0.60 long, 1.13 wide, with three cuspules ( Fig. 11 ). Endites with 22 cuspules. Sternum 3.90 long, 2.75 wide. Posterior sternal sigilla median and submarginal; median and anterior sigilla present, slightly noticeable ( Fig. 11 ). Palp: measurements: femur 3.18/ patella 1.62/ tibia 2.34/ cymbium 1.17/ total 8.31; spination: femur p0­0­1, patella p2, tibia r0­0­1, v0­1­0, p0­1­1, cymbium 0. Legs: measurements: I: femur 5.52/ patella 3.24/ tibia 3.90/ metatarsus 4.32/ tarsus 2.46/ total 19.26; II: 5.10/ 2.88/ 3.48/ 4.20/ 2.52/ 18.18; III: 5.10/ 2.67/ 3.48/ 5.52/ 3.18/ 19.95; IV: 6.24/ 3.06/ 4.08/ 7.29/ 3.30/ 24.69; spination: I: femur d2­3­3, patella p3, tibia v3­2 ­1 (1ap), p1­1­0, p0­0­1, patella d3, tibia v3­2 ­0 (2ap), p1­1­0, metatarsus d0­2­2, r0­1­1, v2­1 ­2, p0­1­1; megaspine absent, metatarsus d0­1­0, r0­1­1, v2­2 ­0, p2­0­1, tarsus 0; II: femur d2­3­4, p0­0­1, patella d3, tibia v3­2 ­0 (2ap), p1­1­0, metatarsus d0­2­2, r0­1­1, v2­1 ­2, p0­1­1; III: femur d2­4­4, patella d1, p3, tibia d3­0­2, v2­2 ­3ap, p1­0­1, metatarsus d2­3­3, v2 ­0­ 5, tarsus r0­0­1; IV: femur d1­3­5, patella r1, p2, tibia d2­0­1, r1­0­1, v2­2 ­0 (2ap), p1­0­1, metatarsus d2­2­3, v1­3 ­5, p1­1­1, r0­1­0, tarsus 0. Scopulae present in all tarsi. Scopulae of tarsi IV divided by a row of thin setae. Scopulae present on 2/3 of metatarsi I–II. Tarsi I–IV with inconspicuous pseudosegmentation. Superior tarsal claws large with a double row of 5–6 teeth on tarsi I and IV and 6–8 on tarsi II and III. Third claw absent on tarsi I–IV. Four spinnerets ( Fig. 6 ). Apical segment of the PLS triangular ( Fig. 7 ). Total length of PLS 2.65. Palp with elongate tibia.

Variation. Total length: 14.22–20.30. Coloration of carapace and legs varies from dark yellow to dark brown. Coloration pattern abdomen dorsum yellow with two paramedian dark stripes ( Figs. 7–8 ), brown with cream colored stripes ( Figs. 9–10 ), or uniformly dark brown. Endites with 20–29 cuspules and labium with 2–4. Few specimens with ventralretrolateral preening comb on metatarsi IV. Few specimens with scopulae of tarsi IV divided by thick setae; Few males with conspicuous pseudosegmentation ( Fig. 13 ).

Female: Unknown.

Distribution. Central Brazil. Mato Grosso, Mato Grosso do Sul, Goiás, Distrito Federal.

Figures

FIGURES 1 – 3. Longistylus ygapema n. sp. 1 – 3. Left male palpal bulb. 1, Prolateral view; 2, Dorsal view; 3, Retrolateral view. Scale bars = 1 mm.

FIGURES 4 – 10. Longistylus ygapema n. sp. 4 – 10. 4, Male body, dorsal view; 5, Cephalothorax, dorsal view; 6, Abdomen, ventral view; 7, Lateral view; 8, Ventral view; 9, Lateral view, showing color variation; 10, Dorsal view, showing color variation. Scale bars = 2 mm. Photos: R. P. Indicatti.

FIGURES 11 – 18. Longistylus ygapema n. sp. 11 – 18. 11, Male sternum, endites and ratellum. 12, Tibia I, retrolateral view; 13, Tarsus IV pseudosgmentation, lateral view; 14, Tarsus IV pseudosegmentation, variation, lateral view; 15, Tarsus IV pseudosegmentation, variation, lateral view; 16, Male palpal bulb, prolateral view; 17, Retrolateral view; 18, Ventral view. Scale bars = 2 mm. Photos: R. P. Indicatti.