Meotipa sahyadri, Kulkarni, Siddharth, Vartak, Atul, Deshpande, Vishwas & Halali, Dheeraj, 2017

Kulkarni, Siddharth, Vartak, Atul, Deshpande, Vishwas & Halali, Dheeraj, 2017, The spiny theridiid genus Meotipa Simon, 1895 in India, with description of a strange new species with translucent abdomen and a phylogenetic analysis about the genus placement (Araneae, Theridiidae), Zootaxa 4291 (3), pp. 504-520 : 506-515

Meotipa sahyadri new species

( Figs. 1–38 )

Diagnosis. The eXceptionally tall and thin abdominal projection is characteristic for female Meotipa sahyadri n. sp. ( Figs. 12, 13 ). This species is morphologically and geographically distributed close to Meotipa picturata ; morphologically for presence of rod-shaped projection in epigynal atrium, but distinguishable by its trifid ( Figs. 19, 22 ) (vs. flat, quandrangular ( Figs. 43, 44 )) shape, shorter and wider copulatory ducts (vs. narrow, long) and spermathecae being separated by less than their diameter. Copulatory duct 2.1 times longer than spermatheca width ( Figs. 18, 23 ) (vs. 3.5 times longer ( Figs. 42 )). Width of epigynal projection at tip 0.5 times atrium radius ( Fig. 22 ), (vs. equal to atrium radius ( Fig. 43 )). Males of M. sahyadri n. sp. have straight embolus ( Figs.29–31 ) (vs. coiled in Meotipa bituberculata Deeleman-Reinhold, 2009 , Meotipa impatiens Deeleman-Reinhold, 2009 ) eXceeding 1.7 times conductor length (vs. about 1.3 times in Meotipa spiniventris (O. Pickard-Cambridge, 1869) , 1.1 times in Meotipa vesiculosa Simon, 1895 , receding in Meotipa argyrodiformis (Yaginuma, 1952) , Meotipa pulcherrima (Mello-Leitão, 1917) and Meotipa thalerorum Deeleman-Reinhold, 2009 ).

For differential diagnosis to female Meotipa species, refer Table 1.

Etymology. The species is named after ‘Sahyadri’ (noun in apposition), a Sanskrit vernacular name for the northern Western Ghats which comprise all localities of the new species.

Type material. Holotype female, ( BNHS Sp. 358), 12.i.2016, Botanical Garden , Yashavantrao Chavan Institute of Science, Satara (17.685 N, 74.011 E, 707 m), INDIA, coll. S. Kulkarni & V. Deshpande.

Additional material studied. 1 male, 1 female (BNHS), Xi.2011, (type locality), coll. S. Kulkarni; 1 female (BNHS Sp. 71), (type locality), iX.2013, coll. S. Kulkarni and Y. Koli; 1 female (BNHS Sp. 98), (type locality), viii.2012, coll. S. Kulkarni; 3 females, (BNHS) X.2016, (type locality), coll. S. Yadav. 1 male, 1 female ( BNHS Sp. 357), 16.Xi.2014, Sanguem (15.229 N, 74.150 E, 58.9 m), Goa, INDIA, coll. D. Halali . 1 female, iX. 2014, near Bharuch (21.658 N, 72.956 E, 30.9 m), Bharuch District , Gujarat, INDIA, coll. P. Patel . 2 male, 9 females, ( BNHS Sp. 359), 14.i.2015, near Boisar (19.800 N, 72.707 E, 13 m), Maharashtra, INDIA, coll. A. Vartak . 1 female, ( BNHS), iX. 2013, Devihansol (16.744 N, 73.427 E, 140.5 m), Ratnagiri District , Maharashtra, INDIA, coll. S. Kulkarni .

Description. Female (holotype).

Measurements. Total length— 5.4 mm, Carapace length— 1.93 mm, width— 1.5 mm, height— 1.08 mm. Abdomen length— 3.3 mm, height— 5.1 mm, Leg I—5.38/0.55/3.56/4.42/0.69, Leg II—3.78/0.55/2.21/3.14/0.71, Leg III—2.8/0.51/1.8/2.3/0.7, Leg IV—4.98/0.67/3.07/4.56/0.85.

Medium-sized, grossly yellowish-white spider.

Cephalothorax: Carapace with dark brown inverted ‘Ψ’ (psi) mark, lateral margins brown ( Fig. 1 ). Clypeus with mid-longitudinal brown stripe, narrowed at base, four times longer than AME diameter. AME dark eXcept on lateral sides, all other eyes pearly white ( Fig. 2 ). Chelicerae white, surface smooth, bearing one anterior, two promarginal, one retro-marginal tooth; whiskered PES at base and stridulatory ridges on dorso-lateral and ventrolateral surface ( Fig. 3 ). Fang surface dorsally smooth, ventrally serrated ( Figs. 3, 4 ). Labium trapezoid, maXillae oval, both pale white; sternum sub-triangular, folded inwards at coXae ( Fig. 5 ). In lateral view, cephalic region flat, thoraX elevated distally ( Fig. 6 ).

Legs: Legs slender, with brown, discrete rings on femora, tibia distally brown, metatarsus apically darker; black FS on patella to tibia ( Fig. 7 ); these setae longitudinally striated, bearing spinules and sharp apically ( Fig. 9 ). Cylindrical, forwardly pointed setae bearing spinules on all legs ( Fig. 9 ). Tibia, metatarsus bearing row of slit sensilla ( Fig. 9 ) and short trichobothria ( Figs. 9, 10 ). Tarsal comb with elevated base, straight serrations, distinctly notched ( Fig. 11 ) typical to that of Theridiinae ( Agnarsson 2004).

Abdomen: tall, colour pale yellow, mottled with pearly white guanine spots, scattered brown, black pattern on dorsum ( Fig. 12 ); laterally white, basal one-third white translucent in live specimens ( Fig. 13 ) (turned opaque white in ethanol); back side of abdominal apeX margined with dark brown lines; black FS on apeX and base ( Fig. 8 ).

Spinnerets: Spinnerets white with pair of brown dots and lines laterally. Arrangements of spigots on ALS, PMS, PLS similar to that of other Theridiinae ( Fig.14 ). About 40 piriform spigots on ALS ( Fig.15 ). One cylindrical spigot on PMS ( Fig.16 ) and two on PLS ( Fig.17 ), each with short base. Flagelliform spigot on PLS longer than its cylindrical spigot length. Two aciniform spigots on PMS. Shaft of minor ampullate spigot longer than cylindrical spigot on PMS.

Epigynum: small, CD longer than spermatheca diameter ( Fig.18 ). Epigynal projection emerging out medially from atrium ( Fig.19 ), perpendicularly ( Fig.20 ); its length slightly eXceeding rim of atrium, lateral margins curved up to middle margin, converged apically ( Fig.21 ), its head trifid ( Fig. 22 ). CO located underside of this projection.

Epigynal projection: Deeleman-Reinhold (2009) referred this term as ‘rod-shaped projection’ in M.picturata . In both, M. sahyadri n. sp. and M.picturata , it arises from the inward fold of upper margin of atrium ( Figs. 22 , 43 ) and CO located underside of it.

Variation (in females). Total length in 15 other females: 4.5 mm – 5.6 mm, abdominal height: 4.7 mm – 6.1 mm. The inverted ‘Ψ’ (psi) mark on carapace discrete in 9 females. Flattened setae on legs and abdomen detach easily in alcohol.

Description. Male. Measurements. Total length— 1.25 mm, Carapace length— 0.59 mm, width— 0.39 mm, height— 0.35 mm. Abdomen length— 0.66 mm, height— 0.83 mm, Leg I—1.28/0.18/0.9/1.17/0.48, Leg II—0.8/ 0.51/1.8/2.3/0.7, Leg III—0.77/0.20/0.52/0.66/0.32, Leg IV—0.85/0.16/0.45/0.87/0.39.

Small-sized, grossly yellowish-white at life, pattern similar to female ( Fig. 24 ).

Cephalothorax: Carapace with complete mid-longitudinal brown stripe ( Fig. 25 ), flat, covered with long setae. Clypeus with mid-longitudinal brown stripe, 2.2 times longer than AME diameter. Eye arrangement and colour similar to female. Chelicerae, labium, maXillae pale white ( Fig. 26, 27 ). Labium trapezoid, maXillae oval, both pale white; sternum sub-triangular, 1.7 times longer than wide, uniform margin at coXae ( Fig. 27 ).

Legs: Colour pattern similar to female, with cylindrical forwardly pointed setae, devoid of flattened setae.

Abdomen: pale white devoid of any translucence, with dark green spots on dorsum and venter, white guanine patches laterally. Abdominal shape triangular in lateral view, not elevated in comparison to female ( Fig. 28 ).

Palp: Conductor mostly membranous, folded along length, broader and chitinous apically ( Figs. 29, 30 ). Embolus eXceeding conductor length ( Figs. 29–31 ), broader at base, narrow apically ( Fig. 32 ). Tegulum and subtegulum separated by thin margin ( Fig. 33 ).

Distribution. Known from localities in the northern Western Ghats in India (see material eXamined, map Fig. 45 ).

Natural History. Females were observed with egg cases during post-monsoon months of September-October ( Fig. 34 ). We observed more than one male on a female’s web. The rarity of males is known in Meotipa , where seX ratio is biased towards females ( Deeleman-Reinhold 2009). We collected 3 males and 18 females, however since our sampling was occasional, seX ratio in M. sahyadri n. sp. was not quantified.

The sampling sites included a botanical garden (type locality) and secondary forest (other localities) where we found that M. sahyadri n. sp. constructs web only on broad leaved plants viz. Fig Ficus sp., Teak Tectona grandis and Chapha Plumeria sp., at a height between 1–3 metres above the ground, but we did not locate them above 3 metres height. Each leaf had only one female web, although a branch with three leaves had a female on each. A caterpillar was observed captured in the web and being fed by female spider ( Fig.35 ).

The resting position of adult and sub-adult female M. sahyadri n. sp. ( Fig. 36 ) is similar to other Meotipa species during the day as described by Deeleman-Reinhold (2009); males are active diurnally. It remains motionless during the day, active during dark and has small web restricted to underside of leaf.

On a teak tree leaf located in busy industrialized region, a darker colour morph of M. sahyadri n. sp. was collected ( Fig. 37 ). We could not locate any more specimens in that region or such darker forms in other localities. In spite of the darker body colour, the translucent part of abdomen and legs observed. Eggs were visible from the translucent part of abdomen.

There is no significant ontogenic colour variation based on our observations of first, second, third instars and adults of 28 live specimens from the type locality. We are not sure if the white translucence at part of abdomen is devoid of pigments and eXploring that is beyond the scope of this paper. Some females had black deposition below the hypodermis of abdomen ( Fig.38 ), possibly eXcretory product; however, we could not determine its nature.

Figures

FIGURE 45. Distribution of specimen records of Meotipa sahyadri n. sp. and Meotipa picturata.

FIGURES 1 – 6. Meotipa sahyadri n. sp., female from India, holotype. 1 Carapace, dorsal vieW 2 Cephalothorax, frontal vieW 3 Chelicera base, dorsal vieW 4 Chelicera base, ventral vieW 5 Cephalothorax, ventral vieW 6 Cephalothorax, lateral vieW. Scale lines: 0.75 mm (Figs. 1 – 2); 0.5 mm (Figs. 5 – 6).

FIGURES 7 – 11. Meotipa sahyadri n. sp., female 7 Flattened setae on Leg IV 8 Flattened setae at abdomen base 9 Flattened, Cylindrical setae, Slit sensillum (inset and arroW) on leg IV 10 trichobothrium on leg IV 11 Tarsal comb on tarsus IV, close-up (inset). Scale lines: 0.75 mm (Fig. 7 – 8).

FIGURES 12 – 17. Meotipa sahyadri n. sp., female 12 Live female, anterior vieW 13 Live female, lateral vieW (note the translucent part of abdomen) 14 Spinnerets 15 Anterior lateral spinnerets 16 Posterior median spinnerets 17 Posterior lateral spinnerets.

FIGURES 18 – 23. Meotipa sahyadri n. sp., epigynum 18 dorsal vieW 19 antero-ventral vieW tilted at 45 degrees 20 Ventral vieW 21 Posterior vieW 22 Epigynal projection 23 glands on spermathecal surface. Scale lines: 0.1 mm (Figs. 18 – 21).

FIGURES 24 – 28. Meotipa sahyadri n. sp., male 24 live on female Web 25 habitus, dorsal vieW 26 cephalothorax, anterior vieW 27 Habitus, ventral vieW 28 Habitus, lateral vieW. Scale lines: 0.5 mm (Figs. 25, 27 – 28); 0.2 mm (Fig. 26).

FIGURES 29 – 33. Meotipa sahyadri n. sp., male, left palp 29 ventral vieW 30 retro-lateral 31 pro-lateral vieW 32 Mesal vieW 33 Dorsal vieW. Scale lines: 0.1 mm (Figs. 29 – 30).

FIGURES 34 – 38. Meotipa sahyadri n. sp., live female 34 With egg sac, underleaf 35 feeding on caterpillar 36 typical ‘ Meotipa’ resting position 37 melanized form 38 unknoWn deposition in translucent part of abdomen.

FIGURES 39 – 44. Meotipa picturata, female. 39 habitus dorsal vieW 40 habitus, lateral vieW 41 habitus, ventral vieW 42 epigynum, dorsal vieW 43 epigynum, ventral vieW 44 copulatory openings at base of atrium. Scale lines: 1 mm (Figs. 39 – 41); 0.1 mm (Fig. 42).