Tissahamia karuna Huber 2019, sp. n.
Creators: name: Huber, Bernhard A.
Publisher: name: Zenodo
Year: 2019
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Araneae
Pholcidae
Tissahamia
Tissahamia karuna

description: Tissahamia karuna sp. n.
Figures 97–98, 107–111, 116–117, 120–121
Diagnosis. Males are easily distinguished from most similar species (T. maturata Huber, 2011) by details of palp: coxa with finger-shaped ventral process (Fig. 109); prolateral process of main bulbal process (‘appendix’) small and weakly sclerotized (Fig. 117); procursus shorter, without sclerotized prolateral process between proximal and distal elements and with larger distal elements (Fig. 110). Females are barely distinguishable from T. maturata but seem to have consistently more weakly sclerotized epigyna and the anterior epigynal margin more curved (Fig. 120).
Etymology. The species name is derived from the Pāli word karuṇā, one of the four Buddhist virtues or brahmavihāras (identifying the suffering of others as one's own); noun in apposition.
Type material. SRI LANKA: ♂ holotype, ZFMK (Ar 20065), Western Province, Labugama Forest (6.846°N, 80.175°E), 150 m a.s.l., 20.iii.2017 (B.A. Huber).
Other material examined. SRI LANKA: 1♂ 1♀, NMSL, 6♂ 8♀, ZFMK (Ar 20066–67), and 4♀ in pure ethanol, ZFMK (SL167), same data as holotype. 3♂ 3♀, ZFMK (Ar 20068), and 1♂ 2♀ in pure ethanol, ZFMK (SL97), Western Province, Mitirigala Forest (6.997°N, 80.175°E), 70 m a.s.l., 6.iii.2017 (B.A. Huber). 2♀ in pure ethanol, ZFMK (SL105), Sabaragamuwa Province, near Kitulgala (6.985°N, 80.430°E), 170 m a.s.l., 7.iii.2017 (B.A. Huber). 1♀, ZFMK (Ar 5088) (this female was erroneously assigned to Pholcus maturat a in Huber 2011), Western Province, Avissawella [6.953°N, 80.218°E], 3.viii.1996 (S.P. Benjamin).
Description. Male (holotype). MEASUREMENTS. Total body length 4.4, carapace width 1.0. Distance PME- PME 400 µm, diameter PME 100 µm, distance PME-ALE 40 µm; AME absent. Sternum width/length: 0.63/0.47. Leg 1: 37.9 (8.8 + 0.4 + 9.0 + 17.6 + 2.1), tibia 2: 5.9, tibia 3: 3.3, tibia 4: 5.3; tibia 1 L/d: 113. Femora 1–4 width (at half length): all 0.09.
COLOR (in ethanol). Carapace mostly dark brown to black, including ocular area and clypeus, only lateral margins and beside ocular area whitish; sternum brown; legs pale ochre-yellow, patellae and tibia-metatarsus joints dark brown to black; abdomen pale with dark marks dorsally and laterally, ventrally monochromous.
BODY. Habitus as in Fig. 97; ocular area slightly raised, each triad on short stalk, with curved pointed process (~100 µm long) arising from median margin of each PME; with small process (~20 µm long) in place of AME; carapace without median furrow; clypeus and sternum unmodified.
CHELICERAE. As in Fig. 116, with pair of weakly sclerotized processes proximally, without distal modification.
PALPS. As in Figs 107–109; coxa with finger-shaped ventral process (longer than in T. maturata and T. kottawagamaensis; cf. Huber 2011: figs 805–806; Dong et al. 2016: figs 5A–B); trochanter with short retrolaterodorsal and longer pointed retrolatero-ventral apophyses, very similar to T. kottawagamaensis; femur with dorsal hump and ventral process pointing toward proximal; tarsus with whitish elongation with tarsal organ at its tip; procursus complex (Figs 110–111), with bifid dorsal process partly covered retrolaterally by transparent membrane, prolateral tip of bifid process connected to strong ridge that leads to ventral ‘knee’ and borders ventral pocket; distally with ventral hinged sclerite; genital bulb with simple membranous embolus and large heavily sclerotized bulbal process (‘appendix’) with small weakly sclerotized prolateral process (Fig. 117).
LEGS. Without spines and curved hairs, few vertical hairs; retrolateral trichobothrium on tibia 1 at 3%; prolateral trichobothrium absent on tibia 1; tarsus 1 pseudosegments not seen.
Male (variation). Tibia 1 in 9 other males: 6.8–9.0 (mean 8.2). Males from Mitirigala with slightly wider tip of appendix and with small conical process on proximal part of bifid dorsal process of procursus (asterisk in Fig. 110).
Female. In general similar to male but carapace mostly light with small U-shaped dark mark (Fig. 98), triads closer together (distance PME-PME 210 µm), without processes arising from near PME, without small process in place of AME. Tibia 1 in 13 females: 6.4–7.2 (mean 6.8). Epigynum as in Fig. 120; with weakly sclerotized epigynal plate and finger-shaped semi-transparent process (‘knob’) arising at anterior margin on epigynal plate (not visible in Fig. 120); whitish rugose area in front of epigynal plate bordered anteriorly by dark internal arc (‘valve’) visible through cuticle. Internal genitalia as in Fig. 121, with pair of oval pore plates.
Natural history. This species built its domed web connected to the underside of live leaves. Webs were sometimes shared with many cecidomyiid flies. At Labugama, the spiders were found in the forest as well as in very disturbed secondary vegetation.
Distribution. Known from four localities in southwestern Sri Lanka (Fig. 225).
description: Published as part of Huber, Bernhard A., 2019, The pholcid spiders of Sri Lanka (Araneae: Pholcidae), pp. 1-57 in Zootaxa 4550 (1) on page 27, DOI: 10.11646/zootaxa.4550.1.1, http://zenodo.org/record/2625030