Losdolobus xaruanus, Lise, Arno A. & Almeida, Luciano, 2006

Lise, Arno A. & Almeida, Luciano, 2006, A new species of Losdolobus Platnick & Brescovit, 1994 (Araneae: Dysderoidea: Orsolobidae) from southern Brazil, Zootaxa 1277, pp. 23-27 : 24-27

Losdolobus xaruanus n. sp.

Figs 1–18

Types. Male holotype and female allotype from Palmas, Bagé, Rio Grande do Sul, Brazil, Luciano Almeida leg., deposited in MCTP 17.550 and MCTP 17.551, respectively.

Etymology. The specific name is a Latinized adjective taken from the Brazilian Xarrua Indians that were the earlier inhabitant of the area.

Diagnosis. This species is similar to L. ybypora . The males can be differentiated of it by the presence of an elongated tibia of palpus and filiform embolus. Females with non conspicuous secretory glands on the genitalia, by shape of the epigynum and by a not inflated tibia of the palpus and by the presence of a very narrowed rod.

Description. Male (holotype). Conditions. missing right leg IV. Carapace, labium, endites and sternum yellow. Chelicerae yellow, fang fulvous with some bristles on the anterior face and long ones on the apical promargin. Legs yellow. Abdomen yellow with dusky almost circular spots of different sizes on dorsum and laterals ( Figs 1, 3 ), venter yellow ( Fig. 2 ). Spinnerets yellow, bristly.

Total length 2.60. Carapace oval, 1.00 long, 0.84 wide, 0.40 high ( Fig. 1 ) Chelicerae 0.40 long, 0.20 wide. Clypeus 0.06 high. Labium triangular, 0.16 long, 0.16 wide. Endites 0.34 long, 0.14 wide at the apical third. transversely excavated, bristly. Sternum 0.60 long, 0.60 wide, not produced anteriorly, truncated posteriorly, marginated by a narrow fulvous band, with precoxal triangles on each leg ( Fig. 2 ). Legs yellow with long slender dark bristles. Abdomen ( Figs 1–3 ), 1.50 long, 1.00 wide, 1.00 high. Eyes pearly white, surrounded with black. Eye diameter and interdistances ALE 0.08 long, 0.07 wide, PME 0.08 long, 0.05 wide, PLE 0.09 long, 0.08 wide, PME–PME 0,0 4, PME–PLE 0.07, PME –ALE 0.04, PLE–PLE 0.26, ALE–PLE touching. Leg spination. III femur 1v apical; tibia d0­1­0; r0­0­.1; v0­0­2; metatarsus p1­0­1, r1­0.1; IV fêmur p1 apical; tíbia p1­1­1­; r0­0­ 1; metatarsus p1­1­1­; r1­0­1; v2 ­0­2. Leg measurements I femur 1.10/patella 0,50/tibia 1.00/metatarsus 0.98/tarsus 0.46/total 4.04; II 1.10/0.50/1.00/1.00/0.46/4.06; III 0.86/0.40/ 0.74/0.80 /0.36 /3.16; IV 1.24/0.42/1.10 / 1.24 /0.40/4.40. Palpus femur 0.64 long, 0.14 wide, patella 0.30 long, 0.14 wide, tibia 0.56 long, 0.16 wide, cymbium 0.50 long, 0.08 wide, bulb plus embolus 0.56 long, 0.20 wide. Palpal bulb longer than wide, simple with long and acuminate embolus and sinuous reservoir ( Figs 5–7 ).

Female (allotype). Conditions. right leg II missing from patella to tarsus; left leg II only has atrophied coxa and trochanter; from right leg I and III it was removed tibia, metatarsus and tarsus for SEM purposes. Carapace, chelicerae, labium, sternum and endites yellow. Abdomen yellow grayish without the gray spots observed on the male. Spinnerets yellow.

Total length 2.90. Carapace 1.20 long, 0.88 wide, 0.44 high. Abdomen 1.66 long, 1.20 wide, 1.20 high. Eye diameters and interdistances ALE 0.09 long, 0.05 wide, PME 0.09 long, 0.07 wide, PLE 0.08 long, 0,0 7 wide, PME–PME 0.02, PME–PLE 0.07,PME–ALE 0.02, PLE–PLE 0.28. Chelicerae 0.50 long, 0.20 wide. Labium 0.16 long, 0.24 wide. Endites 0.34 long, 0.16 wide. Sternum as long as wide, 0.60. Leg spination: I femur d1 median, tibia v1; III tibia d1 median, p1.1, r1.1, v2.2; metatarsus p1.1, v2.2; IV tibia p1.1, r1.1, v2.1.1.2; metatarsus p1.1.1, r1.0.1, v1.1.2. Leg measurements I femur 1.04/patella 0.50/tibia 0.86/metatarsus 0.90/tarsus 0.36/total 3.66; II femur 1.00; III. 0.84/0.40/ 0.64/ 0.80/0.30/2.98; IV 1.20/0.46/0.94/1.12/0.40/4.12. Tarsal organ ( Figs15–16 ) with three short central receptor lobes and six very long and acuminate cuticular ones. Claws long with few long teeth on the lateral flange. Claw tuffs constituted by different types of bristles and hairs ( Figs 13–15 ). On top of tarsus, above the claws, there are two long curve chaetae pointed forward, ventrally two more, shorter than the dorsal ones ( Fig. 13 ). Bothrium smooth with elliptical tricheme aperture and transversely depressed forming two widely spaced transverse ridges. Trichobothriae typical for family ( Fig. 18 ). Proprioreceptors bristle plumose ( Figs 11–17 ). Gland pore plate as in figure 12. Palpal tibia not dilated ( Fig. 8 ). Internal genitalia as in ( Fig. 10 ).

Distribution. Known only from the type locality.

Figures

FIGURES 1 – 10. Losdolobus xaruanus n. sp. 1 – 7 male. 1 – 3 habitus (1 dorsal, 2 ventral, 3 lateral); 4 carapace and chelicerae, frontal; 5 – 7 palpus (5 prolateral, 6 retrolateral, 7 ventral); 9 – 10 female genitalia (9 ventral, 10 dorsal).

FIGURES 11 – 18. Female leg details. 11 metatarsus III and joint with tarsus, dorsal, showing gland pore plate and proprioreceptor; 12 gland pore plate, detail; 13 tarsus, lateral, showing claws with dense claw tufts of spatulated hairs; 14 right tarsus I, distal view; 15 tarsus with tarsal organ and proprioreceptors; 16 tarsal organ, detail; 17 proprioreceptor; 18 trichobothria.