Belisana gowindahela, Huber, 2019

Huber, Bernhard A., 2019, The pholcid spiders of Sri Lanka (Araneae: Pholcidae), Zootaxa 4550 (1), pp. 1-57 : 8-9

Belisana gowindahela sp. n.

Figures 6–7 , 31–33 , 38–39

Diagnosis. Easily distinguished from most congeners by long retrolateral process (‘flap’) of procursus pointing in proximal-ventral direction and curved at tip ( Figs 32–33 ); from very similar B. ratnapura Huber, 2005 by more slender procursus with different shape of prolateral distal sclerite (compare Figs 32–35 ), by wider distance between distal male cheliceral apophyses (~80 µm versus 15 µm in B. ratnapura ; compare Fig. 31 with fig. 604 in Huber 2005), and by epigynum without posterior extension and with pockets wider apart (~60 µm versus 10–15 µm in B. ratnapura ; compare Figs 38–41 ).

Etymology. The specific name is derived from the type locality (noun in apposition).

Type material. SRI LANKA: ♂ holotype, ZFMK (Ar 20006), Uva Province, near Gowindahela (7.041°N, 81.538°E), 130–180 m a.s.l., 12.iii.2017 (B.A. Huber) .

Other material examined. SRI LANKA: 7♂ 7♀ 1 juv., ZFMK (Ar 20007), and 1♂ 1♀ in pure ethanol, ZFMK ( SL135 ), same data as holotype . 3♂ 5♀ 4 juvs, ZFMK (Ar 20008), and 1♂ 1♀ in pure ethanol, ZFMK ( SL131 ), Uva Province, Inginiyagala (7.225°N, 81.535°E), 110 m a.s.l., 12.iii.2017 (B.A. Huber) . 1♀, ZFMK ( Ar 20009), and 1♀ in pure ethanol, ZFMK ( SL127 ), North Central Province, Dimbulagala (7.860°N, 81.118°E), 140 m a.s.l., 11.iii.2017 (B.A. Huber) . 3♂ 5♀, ZFMK (Ar 20010), and 1♀ 1 juv. in pure ethanol, ZFMK ( SL121 ), Central Province, Kandalama Forest (7.859°N, 80.711°E), 220 m a.s.l., 10.iii.2017 (B.A. Huber) . 1♂ 4♀, ZFMK (Ar 20011), and 2♀ in pure ethanol, ZFMK ( SL115 ), North Western Province, Kurunegala, at base of Ethagala ( Athugala ) Mtn (7.490°N, 80.369°E), 170 m a.s.l., 9.iii.2017 (B.A. Huber) . 1♂ 1♀, NMSL , 8♂ 11♀, ZFMK ( Ar 20012–13), and 2♀ in pure ethanol, ZFMK ( SL110 ), Central Province, Kandy, Dunumadallawa Forest (7.282°N, 80.643°E), 600–680 m a.s.l., 8.iii.2017 (B.A. Huber) . 1♂ 1♀ 1 juv., ZFMK (Ar 5397), Central Province, Kandy, Udawattakele Sanctuary [7.300°N, 80.642°E], 17.iii.1998 (S.P. Benjamin) ; 2♀ 2 juvs, ZFMK ( Ar 5197), same data but 18.vii.2003 . 9♂ 10♀, ZFMK (Ar 20014), and 2♀ 1 juv. in pure ethanol, ZFMK ( SL152 ), Sabaragamuwa Province, above Dematagala (6.451°N, 80.751°E), 160 m a.s.l., 16.iii.2017 (B.A. Huber) .

Description. Male (holotype). MEASUREMENTS. Total body length 1.9, carapace width 0.6. Distance PME- PME 160 µm, diameter PME 60 µm, distance PME-ALE 15 µm; AME absent. Sternum width/length: 0.40/0.38. Leg 1: 15.7 (3.9 + 0.3 + 4.0 + 6.0 + 1.5), tibia 2: 2.5, tibia 3: 1.5, tibia 4: 2.3; tibia 1 L/d: 67.

COLOR (in ethanol). Entire spider whitish to pale ochre-yellow, legs without dark rings.

BODY. Habitus as in Fig. 6 ; ocular area not raised; carapace without median furrow; clypeus and sternum unmodified.

CHELICERAE. As in Fig. 31 , with pair of small apophyses proximally laterally, pair of short frontal apophyses distally, and pair of indistinct frontal apophyses proximally; distance between tips of distal apophyses 0.08.

PALPS. Proximal segments very similar to B. ratnapura (cf. Huber 2005: figs 602–603); coxa unmodified; trochanter with distinctive retrolateral apophysis; procursus as in Figs 32–33 , with long retrolateral flap and distinctive prolateral distal sclerite; bulb apparently indistinguishable from B. ratnapura .

LEGS. Without spines and curved hairs; few vertical hairs; retrolateral trichobothrium on tibia 1 at 9%; prolateral trichobothrium apparently absent on tibia 1; tarsus 1 with ~25 pseudosegments, distally distinct.

Male (variation). Tibia 1 in 32 other males: 3.2–4.3 (mean 3.7).

Female. In general similar to male; tibia 1 in 44 females: 2.8–3.4 (mean 3.1). Epigynum externally very simple, barely distinguishable from surrounding cuticle, with pair of pockets ~58–60 µm apart, not on posterior extension. Internal genitalia as in Figs 38–39 , with pair of small pore plates far apart.

Natural history. This leaf-dwelling species was very abundant at some sites (e.g. Kandy). Its web was attached to the underside of a leaf and was highly regular, consisting of long parallel vertical lines connected by short horizontal lines (i.e. without the zig-zag lines present in the webs of many other Belisana species).

Distribution. Widely distributed in central and eastern Sri Lanka, apparently excluding high elevation areas ( Fig. 221 ).

Figures

FIGURES 1–9. Belisana, live specimens. 1–3. B. minneriya sp. n., males and female with egg-sac from Minneriya. 4–5. B. keyti Huber, 2005, male and female with egg-sac from Hakgala. 6–7. B. gowindahela sp. n., male from Ethagala, female with egg-sac from Dematagala. 8–9. B. ratnapura Huber, 2005, male from Mapalena Ella, female with egg-sac from Viharekele.

FIGURES 31–35. 31–33. Belisana gowindahela sp. n. (ZFMK Ar 20007). 31. Male chelicerae, frontal view. 32–33. Left procursus, prolateral and retrolateral views. 34–35. B. ratnapura Huber, 2005 (ZFMK Ar 20015), left procursus, prolateral and retrolateral views (all procursi at same scale). Scale lines: 0.2 mm.

FIGURES 36–41. Cleared female genitalia in ventral and dorsal views. 36–37. Belisana minneriya sp. n. (ZFMK Ar 20000). 38–39. Belisana gowindahela sp. n. (ZFMK Ar 20007). 40–41. B. ratnapura Huber, 2005 (ZFMK Ar 20015). Abbreviations: po, pocket(s); pp, pore plate. Scale lines: 0.2 mm.

FIGURES 220–221. Known distribution of Belisana in Sri Lanka.