Ischnocolus Ausserer 1871
Creators: name: Guadanucci, José Paulo Leite
name: Wendt, Ingo
Publisher: name: Zenodo
Year: 2013
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Araneae
Theraphosidae
Ischnocolus

description: Genus Ischnocolus Ausserer, 1871
(Figures 1– 2)
Ischnocolus Ausserer 1871: 185; 1875: 168; Pavesi 1880: 362; Simon 1892: 135; 1903: 925; 1909: 9; Thorell 1899: 9; Strand 1907: 13; 1908: 22; Petrunkevitch 1911: 74; 1928: 78; Mello-Leitão 1923: 385; Bacelar 1932: 171; Roewer 1942: 233; Bonnet 1957: 2302; Gerschman de Pikelin and Schiapelli 1973; Raven 1985; Smith 1990: 122.
Type species. Ischnocolus holosericeus Koch, in Ausserer 1871 by original designation.
Species included. I. valentinus, I. hancocki Smith 1990, I. jickelli Koch 1875, I. ignoratus sp. nov.
Diagnosis
Representatives of the genus can be distinguished from the remaining Ischnocolinae by the clavate tarsal trichobothria with small barbs on the surface and arranged in a short, median apical row (Figure 1A, B) and by the maxillae having a lighter colour on the prolateral edge on the ventral surface than on the retrolateral edge (Figure 2A), in both live and preserved specimens. It is characterized by the absence of a maxillary serrula, posterior lateral spinnerets shorter than the abdomen (contrasting with representatives of the genus Heterothele Pocock), and by the absence of an unpaired claw. Males of Ischnocolus are also recognized by the following features: presence of intercheliceral intumescence (Figure 2B), sigmoid ventral furrow on palpal tibia (Figure 2C), unequal cymbium lobes (Figure 2D), tibial apophysis absent, great number of spines on tibia I (Figure 2E), male superior tarsal claws with two rows of teeth (Figure 2F), and all tarsi cracked (Figure 2G). Females may be also recognized by the narrow clypeus (narrower than the diameter of anterior median eyes) and tarsal scopula I–IV divided.
Description
Chelicerae without rastellum, intumescence present in males (Figure 2B). Cephalic region slightly raised. Eye tubercle weakly raised, small. Anterior eye row procurved, posterior recurved, clypeus narrower than the diameter of anterior median eyes. Thoracic fovea straight or slightly procurved. Labium varying from nearly as wide as long to twice as wide as long, bearing few (4) or several (40) cuspules. Maxillae with pronounced anterior lobe, serrula absent, several cuspules on the inner angle (ranging from 40 to 100 cuspules). Posterior sternal sigilla marginal. Cymbium bilobed, retrolateral lobe much larger than prolateral (Figure 2D). Palpal tibia with sigmoid ventral furrow (Figure 2C). Presence of several spines on male tibia I (Figure 2E). Tarsal scopula I–IV divided by a longitudinal band of thick setae. Male superior tarsal claws bi-pectinate (Figure 2G), claw tufts well developed. Retrolateral scopula on femur IV absent. Stridulatory setae absent. Urticating hairs absent. Posterior lateral spinnerets three-segmented, long, apical article digitiform or triangular. Palpal bulb with long and thin embolus, without keels. Spermathecae formed by two receptacles, with or without lobes.
description: Published as part of Guadanucci, José Paulo Leite & Wendt, Ingo, 2013, Revision of the spider genus Ischnocolus Ausserer, 1871 (Mygalomorphae: Theraphosidae: Ischnocolinae), pp. 387-402 in Journal of Natural History (J. Nat. Hist.) (J. Nat. Hist.) 48 (7 - 8) on pages 389-390, DOI: 10.1080/00222933.2013.809492, http://zenodo.org/record/4632171