Tigidia fasciata, Mirza, 2023

Mirza, Zeeshan A., 2023, Notes on the trapdoor spider genus Tigidia Simon 1892 (Araneae: Barychelidae: Barychelinae) with the description of three new species from India, Journal of Natural History 57, pp. 159-174 : 168-171

Tigidia fasciata sp. nov.

urn:lsid:zoobank.org:act:47C2FBD6-DBDA-4BEF-88E3-107059AC61BA

( Figures 6 , 7 (a–f))

Type material. Holotype ♀ (NRC-AA-1608), INDIA: Kerala, District, Neyyar Wildlife Sanctuary (8.548032°N, 77.145361°E, 143 m), leg. Rajesh Sanap and Zeeshan Mirza, 21.12.2013 . Paratypes: 2♀, NCBS AG803, same data as holotype, and NCBS AG804, Peppara Wildlife Sanctuary (8.672902°, 77.151279°, 380 m) leg . Rajesh Sanap and Zeeshan Mirza, 24.12 .2013 .

Etymology. The specific epithet ′ fasciata ̍ refers to the bands present on the legs of the new species.

Diagnosis. Differs from all Indian congers in bearing spines on all legs in addition to a digitiform spermatheca and chevron abdominal pattern.

Description. Female, total length 11.65. Carapace 4.91 long, 3.52 wide. Fovea 0.48 wide, distance from anterior border 3.08. Abdomen 5.63 long, 3.48 wide. Spinnerets: PLS, total length 1.36 (0.10 basal, 0.40 middle, 0.86 apical; mid widths 0.56, 0.36, 0.17, respectively), 0.24 apart.

Colour in life ( Figure 6 ). Carapace dark blackish brown covered with golden hairs; all legs yellow with distinct black band present on tarsus, metatarsus 2/3 and tibia ¼ on the basal region. Abdomen yellowish with brown chevron marking running from dorsal to lateral sides. Ventral side light yellowish, two small black lines between spinnerets and book lungs. Colour in alcohol paler than in fresh specimen.

Carapace covered with golden hairs all over. Intermixed with black short and long bristles on caput. Bristles: 2–3 long and 3 short on the caput in mid-dorsal line; 3–4 long and 11–12 short between PME; two glabrous bands emerging from fovea and running either side of caput.

Eyes ( Figure 7 (c)). Ocular group front width, mid-width, back width, length, 0.83, 0.71, 0.91, 0.84, respectively. Anterior row strongly procurved, posterior row straight; posterior eyes opaque, rest transparent. MOQ square, front width 0.63, back width 0.68, length 0.47. Diameter of AME 0.19, ALE 0.26, PME 0.10, PLE 0.20. Eye interspaces: AME–AME 0.11, AME– ALE 0.14, PME–PLE 0.07 adjacent, PME–PME 0.29, ALE–PLE 0.24.

Sternum ( Figure 7 (b)). 2.40 long, 2.22 wide. Covered with hair and bristles. Sigilla indistinct.

Chelicerae ( Figure 7 (d)). 3.00 long. Prolateral face glabrous, yellowish orange with a few small hairs; 10 promarginal teeth and 17–18 basomesal teeth in 2–3 parallel lines; rastellum on low mound, consists of ca. 35–40 short thick curved spines, of which 15 on the mound and 13–15 in anterior line, several normal pointed thin spines on dorsal and vertical face and upward; dorsally two glabrous bands for length.

Labium ( Figure 7 (b)). 0.39 wide, 0.57 long; labiosternal groove broad with two sigilla joined medially. Cuspules absent.

Maxillae ( Figure 7 (b)). 1.23 long in front, 1.37 long in back, 0.94 wide; 4/4 cuspules on inner angle. Posterior heel slightly produced; anterior lobe distinct.

Legs. Formula 4123, lengths (femur, patella, tibia, metatarsus, tarsus, total): I: 3.08, 1.84, 2.30, 1.47, 1.26, 9.95. II: 3.07, 1.83, 1.93, 1.25, 1.14, 9.22. III: 2.47, 1.15, 1.63, 1.54, 1.21, 8. IV: 3.57, 1.53, 3.22, 2.60, 1.40, 12.32. Palp: 2.21, 1.09, 1.34, -, 1.40, 6.04. Mid widths: femora I–IV = 1.04, 1.07, 1.05, 0.84, palp = 0.70, tibia I–IV = 1.00, 0.85, 0.93, 0.88, palp = 0.99.

Legs. Brown, moderately hairy; femora III and tibia I thicker than rest; all legs of similar thickness; preening comb on ventrolateral metatarsi III and IV; coxae IV widest; two glabrous bands longitudinal on femora, patellae and tibiae (very prominent on patellae).

Leg spination. Legs I and II: 3 v; leg III: mt, 3p, 2 r, 5 v; ti, 2p, 2 r, 5 v; pa, 4p; leg IV: mt, 2p, 2 r, 8 v; ti, 2 r, 6 v.

Scopulae. Ta: I–II, full, thick, lateroventral, divided with thin long hair for length, multiple hair mixed with scopulae at the base; III–IV, full, lateroventral, divided with 3–4 rows of spines for length. Mt III: well developed scopulae on distal half; III–IV, a few scopuliform hairs intermixed with bristles on distal ¼.

Trichobothria. Ta: I, 8 clavate, 8–9 long and short filiform; II, 8 clavate, 10–11 long and short filiform; III, 7 clavate, 15–16 long and short filiform; IV, 7 clavate, 11–12 long and short filiform; palp, 10 clavate, 12–13 long and short filiform. Mt: I, 5–6 long and short; II, 6–7 long and short; III, 14–15 long and short; IV, 12–13 long and short; palp, 12–13 long and short. Ti: I and II, 10–11 long and short; ti: III and IV 7–8 long and short; palp, 12–13 long and short; III, 7 long and short; Clavate trichobothria is confined to proximal half of ta. Short filiform confined to mid-dorsal distal half in a single row, long filiform in V-shaped pattern confined to distal half on ta. Mt, only filiform in curved single row in 2/3 length.

Claws. Claw tufts on all legs and palp. All claws edentate, claws of legs I and II clearly smaller than on legs III and IV.

Abdomen ( Figures 7 (a–b)). Yellow with brown chevron mark dorsolaterally, uniformly covered with short brown hairs intermixed with a few black bristles.

Spinnerets ( Figure 7 (e)). PLS, apical segment dome-shaped. Covered with goldenbrown hair. PMS absent.

Spermathecae ( Figure 7 (f)). 2 digitiform stalks, each with a lateral balloon-like lobe supported by a twisted sclerotised structure emerging outward from close to the base.

Natural history. Specimens were found on mud slopes leading to the Neyyar Lake in Neyyar Wildlife Sanctuary in southern Kerala ( Figure 8 ). The area is dominated by Tectona grandis and is a degraded patch meant for recreational activities for tourists. Burrows were short and in hard soil, usually vertical in orientation. Burrows were short, with two trapdoors leading to a tubular burrow.

Figures

Figure 6. Tigidia fasciata sp. nov. showing colouration in life.

Figure 7. Tigidia fasciata sp. nov. NRC-AA-1608: (a) dorsal, (b) ventral, (c) eyes, (d) prolateral face of chelicerae, (e) spinnerets, (f) spermathecae.

Figure 8. Map showing the distribution of Tigidia spp. in India.