Tigidia tangerina, 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 : 165-168

Tigidia tangerina sp. nov.

urn:lsid:zoobank.org:act:B880308A-48DF-4ABE-BB44-6B9800E2EFC2

( Figures 4 , 5 (a–f))

Type material. Holotype ♀ (NRC-AA-1607), INDIA: Karnataka, Chikkaballapur District, Nandi hills (13.372007°N, 77.680686°E, 1394 m), leg. Rajesh Sanap and Zeeshan Mirza, 28.08.2018 . Paratypes: 2 ♀ (NCBS AG805 and AG806), same data as holotype.

Etymology. The specific epithet ′ tangerina ̍ refers to the orange colouration of the new species in life.

Diagnosis. Differs from T. rutilofronis and T. sahyadri in possessing a digitiform stalk of spermathecae; differs from T. fasciata sp. nov. in bearing spines only on legs III and IV. Differs from T. jalgaonensis sp. nov. in bearing a twisted lateral spermathecal lobe.

Description. Female. Total length 11.44. Carapace 7.09 long, 6.30 wide. Fovea 1.15 wide. Distance from anterior border of carapace 2.65. Abdomen 9.35 long, 6.56 wide. Spinnerets: PLS, total length 1.75 (1.21 basal, 0.41 middle, 0.13 apical; mid widths 0.67, 0.50, 0.17, respectively), 0.39 apart.

Colour in life ( Figure 4 ). Carapace dark brown; legs orange except all legs of tarsus and metatarsus are light orangish brown. Abdomen overall dark blackish brown, darker anteriorly with yellowish-brown chevron marking running from dorsal to lateral side. Colour in alcohol paler than fresh specimens.

Carapace covered with black hairs equally spread all over. Intermixed with black short and long bristles on caput. Bristles: 6 long and 5–6 short on the caput in mid dorsal line; 13 long, 14–15 short between PME; 13–14 long and 3–4 on the border between ALE and ALE; 9–10 short between AME and ALE. Two glabrous bands emerging from fovea and running either side of caput.

Eyes ( Figure 5 (c)). Ocular group front width, mid-width, back width, length, 1.0, 0.90, 1.42, 1.10, respectively. Anterior row and posterior row straight; rest transparent. MOQ square, front width 0.76, back width 1.03, length 0.56. Diameter of AME 0.36, ALE 0.42, PME 0.20, PLE 0.36. Eye interspaces: AME–AME 0.16, AME–ALE 0.25, PME–PLE 0.06 adjacent, PME–PME 0.64, ALE–PLE 0.41.

Sternum ( Figure 5 (b)). 3.75 long, 3.20 wide. Covered with hair and bristles projecting from anterior border of sternum.

Chelicerae ( Figure 5 (d)). 3.00 long. Prolateral face glabrous, brown with a few small hairs; 8 promarginal teeth and 13 basomesal teeth in 2–3 parallel lines; rastellum on a mound, consists of ca. 50 short thick curved spines, of which 17–18 on the mound and 8–9 in anterior line, several normal pointed thin spines on dorsal and vertical face and upward.

Labium ( Figure 5 (b)). 1.30 wide, 0.62 long; labiosternal groove broad with two sigilla joined medially. Cuspules absent.

Maxillae ( Figure 5 (b)). 1.45 long in front, 1.95 long in back, 1.44 wide; 2/3 cuspules on inner angle. Posterior heel slightly produced; anterior lobe indistinct.

Sigilla ( Figure 5 (b)). Distinct/indistinct, posterior 0.20 diameter, 2.31 apart, marginal; median 0.19 diameter, 2.50 apart, marginal; anterior 0.05 diameter, 2.26 apart, marginal.

Legs. Formula 4123, lengths (femur, patella, tibia, metatarsus, tarsus, total) I: 3.30, 2.17, 2.55, 1.64, 1.10, 10.76. II: 3.29, 2.17, 2.22, 1.17, 1.12, 9.97. III: 2.57, 1.80, 1.57, 1.72, 1.28, 8.94. IV: 3.70, 2.34, 2.94, 3.04, 1.53, 13.55. Palp: 2.68, -, 1.71, 1.16, 1.72, 7.27. Mid widths: femora I–IV = 1.12, 1.23, 1.32, 1.09; palp = 0.70. Tibia I–IV = 1.14, 1.07, 0.95, 0.98, palp = 1.01.

Legs. Orange, 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. Leg III: mt, 2p, 1 r; ti, 1p; pa, 3p; leg IV: mt, 2p; ti, 1p; pa: mt, 2p.

Scopulae. Ta: I – II, full, thick, lateroventral, divided with thin long hair for length, multiple hairs mixed with scopulae at the base; III – IV, full, lateroventral, divided with 6 – 7 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, 11 calvate in 3–4 rows, 11 – 12 long and short filiform in two rows; ta: II, 11 calvate in 2–3 rows basal region; 10–11 long and short filiform in two row; ta: III, 8 calvate in two rows; 9–10 long and short filiform in 2–3 rows; ta: IV, 7 calvate in two rows; 8–9 short and long filiform in three rows; mt: I 4–5 long and short on the distal region; mt: II, 10–11 short and long filiform in two rows; mt: III, 7–8 long and short filiform in two rows; mt: IV, 16–17 long and short filiform in two rows; ti: I, 13–14 long and short filiform in three rows; ti: II, 9–10 long filiform in two rows; ti: III, 8–9 long and short filiform in two rows; ti: IV, 12–13 long and short filiform in two rows.

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 ( Figure 5 (a–b)). Blackish brown with yellowish chevron mark dorsolaterally; uniformly covered with short brown hairs intermixed with a few black bristles.

Spinnerets ( Figure 5 (e)). PLS, apical segment dome-shaped. Covered with golden brown hair. PMS absent.

Spermathecae ( Figure 5 (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. The type specimens were collected from Nandi hills along a trail leading to the highest point. Burrows were mostly constructed at the base of large trees in loose soil. The burrows are about 150 mm deep, with a single trapdoor.

Figures

Figure 4. Tigidia tangerina sp. nov. showing colouration in life.

Figure 5. Tigidia tangerina sp. nov. NRC-AA-1607, (a) dorsal, (b) ventral, (c) eyes, (d) prolateral face of chelicerae, (e) spinnerets, (f) spermathecae.