Trilacuna meghalaya Grismado and Piacentini 2014, new species
Creators: name: Grismado, Cristian J.
name: Deeleman, Christa
name: Piacentini, Luis N.
name: Izquierdo, Matías A.
name: Ramírez, Martín J.
Publisher: name: Zenodo
Year: 2014
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Araneae
Oonopidae
Trilacuna
Trilacuna meghalaya

description: Trilacuna meghalaya Grismado and Piacentini, new species
Figures 15–31, 39A–B
TYPES: Male holotype and five paratype males from India: Meghalaya: Garo-Hills: above Tura, 700 m, 25.56000 ° N, 89.49000 ° E, Nov. 1, 1978, C. Besuchet, I. Löbl (MHNG PBI_OON 15401); 10 paratype females with same data (MHNG PBI_OON 15404).
ETYMOLOGY: The specific name is a noun in apposition taken from the type locality.
DIAGNOSIS: Males of this species are similar to those of T. mahanadi by their relatively simple paraembolic projections, but the copulatory bulb has a more truncate shape in the distal part, from where the embolus and accompanying elements arise (figs. 28A–B, 31C–E, 39B), and lack stout epigastric setae. Females are easily recognized by their internal genitalia, with a medium-sized, cylindrical (sinuous in lateral view) posterior receptacle, and curved lateral projections of the anterior sclerite (figs. 22C, D, 39A).
DESCRIPTION: Male (holotype, PBI_OON 15401). Total length 1.66. Cephalothorax: Carapace sides granulate; nonmarginal pars cephalica setae light; marginal setae light, needlelike. Clypeus setae light, needlelike. Eyes ALE, PME subequal, larger than PLE, ALE circular, PLE oval; ALE–PLE separated by less than ALE radius, PME touching for less than half their length. Sternum without radial furrows between coxae I–II, II–III, III–IV, microsculpture covering entire surface, lateral margins unmodified, orange; setae sparse, but densest medially. Mouthparts: chelicerae orange; setae light. Labium with two short, laterally directed ridges. Endites orange, with a set of black, flattened, enlarged setae pointing medially (figs. 24C– D, 30 E). Abdomen: Book lung covers round. Dorsal scutum orange. Epigastric scutum not protruding. Postepigastric scutum covering about 3/4 of abdominal length, orange. Spinneret scutum absent. Dorsum setae light. Epigastric area setae uniform, light. Postepigastric area setae light. Legs: Patella plus tibia I shorter than carapace. Leg spination (all spines longer than segment width): leg I: femora: pv0-0-1-0, tibiae: v2-2-2-2-0, meta-tarsi: v2-2-0, leg II: tibiae: v2-2-2-2-0, meta-tarsi: v2-2-0. Trichobothria: tibia: each with three; metatarsus: each with one; opening longitudinally narrowed; hood covered by numerous low, closely spaced transverse ridges; basal expansion of trichobothrial setae with annular ridges (fig. 26C–G). Tarsal organ with two sensilla visible in the palp (fig. 26H), three in the leg I, one of them very small (fig. 26I). Genitalia: Epigastric region with sperm pore oval, situated at level of anterior spiracles, unmodified. Palp: distal part of the bulb with a truncate shape, with an indentation on the prolateral side, covered with setiform structures, some of them bifid (fig. 28D). Two elongated projections run parallel to the embolus at its prolateral side (fig. 28D), retrolateral surface of embolus bearing numerous spinules (fig. 28H). Two other similarly ‘‘haired’’ projection flank the embolus dorsally and retrolaterally (fig. 28E–F).
Female (paratype, PBI_OON 15404). Total length 1.78. As in male except as noted. Cephalothorax: Carapace nonmarginal pars cephalica setae in U-shaped row. PME circular. Sternum orange. Mouthparts: chelicerae orange; paturon distal region abruptly narrowed. Labium with 3–5 setae on anterior margin. Palp without spines. Abdomen: Dorsal scutum covering full length of abdomen, orange. Spinneret scutum slightly sclerotized. Legs: Femora darker than the subsequent articles. Leg spination as in male. Tarsal organ with two sensilla visible on palp and leg IV (fig. 20A, C), three on leg I, one of them very small (fig. 20B). Spinnerets (fig. 21): ALS and PMS with three spigots, PLS with five spigots. Genitalia: Copulatory opening a small slit posteriorly situated and separated from the epigastric furrow, in the middle of the transverse plates, between them lies a field of presumably glandular tissue (figs. 22E, 39A, we cannot find the external openings). The copulatory opening leads to a more or less cylindrical, medium-sized, posterior receptacle that extends anteriorly (after a short posteriorly directed part) to the vicinity of the epigastric furrow, leading to the uterus externus. The T-shaped anterior sclerite (figs. 22C, 39A), apparently without lumen, has conspicuously curved lateral bars for the attachment of muscles connecting to the lateral parts of one of the transverse plates. Transverse bars with two relatively long, lateral apodemes serve as attachment for other muscles.
OTHER MATERIAL EXAMINED: INDIA: Meghalaya: Khasi Hills: Mawphlang, 1800 m, Oct. 28, 1978, C. Besuchet, I. Löbl, 1♂ (MACN-Ar 28839, PBI _OON 15502); Khasi Hills; below Cherrapunjee, 1200 m, Oct. 26, 1978, C. Besuchet and I. Löbl, 1♀ (MHNG PBI_OON 15392), 1♀ (MACN-Ar 28838, PBI_OON 42097); Khasi-Hills: Nongpoh, 700 m, Nov. 5, 1978, C. Besuchet and I. Löbl, 3♂ (MHNG PBI_OON 12808), 1♂ (MHNG PBI_OON 12876), 2♀ (MHNG PBI_OON 15324), 1♂ (MHNG PBI_OON 16158); Garo-Hills: Songsak, forest floor, bamboo litter, 400m, Nov. 02, 1978, C. Besuchet and I. Löbl, 1♀ (MHNG PBI_OON 15411). Assam: Manas, Manas Wildlife Sanctuary, 200 m, 26.72500 ° N, 91.03600 ° E, Oct. 21, 1978, to Oct. 22, 1978, C. Besuchet, I. Löbl, 1♂ (MHNG PBI_OON 15338).
DISTRIBUTION: Known only from Meghalaya and Assam, northeastern India.
description: Published as part of Grismado, Cristian J., Deeleman, Christa, Piacentini, Luis N., Izquierdo, Matías A. & Ramírez, Martín J., 2014, Taxonomic Review Of The Goblin Spiders Of The Genus Dysderoides Fage And Their Himalayan Relatives Of The Genera Trilacuna Tong And Li And Himalayana, New Genus (Araneae: Oonopidae), pp. 1-108 in Bulletin of the American Museum of Natural History 2014 (387) on pages 30-40, DOI: 10.1206/843.1, http://zenodo.org/record/5379126