Hemitelsella, Smith, 2016

Smith, Graeme B., 2016, On some Silverfish Taxa from Tasmania (Zygentoma: Lepismatidae and Nicoletiidae), Records of the Australian Museum 68 (2), pp. 45-80 : 72-73

Hemitelsella n.gen.

Type species. Acrotelsella transpectinata Smith, 2015 .

Diagnosis. Medium-sized silverfish. Body shape as in Fig. 164 . Pigment present. Macrochaetae variably plumose. Scales multiradiate of variable shape as well as lanceolate. Antennae with both poculiform and rod-like basiconic sensillae. Chaetotaxy of frons consisting of weak bushes of pectinate macrochaetae in the anterolateral corners between the antennae, with the macrochaetae not aligned in distinct rows, with a small gap between this group and further marginal macrochaetae running along the lateral margin and above the eyes; with small 1+1 isolated groups of macrochaetae posterior to the antennal bases. Clypeus and labrum each with 1+1 bushes of pectinate macrochaetae. Eyes of 12 ommatidia.

Apical article of labial palp with long row of sensory papillae. Pronotum with narrow setal collar. Thoracic nota each with several lateral bristlecombs and 1+1 posterolateral combs of one or two macrochaetae positioned quite laterad; all trichobothrial areas open (type 1 of Mendes, 1986) and each associated with a bristlecomb. Thoracic sternites subtriangular to broadly parabolic with posterolateral bristlecombs. Tibiae with many long strong pectinate macrochaetae. Tarsi with four articles all with roundtipped setae below, pretarsus with two claws and a medial empodial claw. Urotergite I with 1+1 and II– VII each with 3+3 bristlecombs, urotergite VIII with 2+2 bristlecombs (lacking the sublaterals), IX glabrous. Urotergite X short, subtriangular with many marginal macrochaetae and with submarginal bristlecombs. Urosternites I –II glabrous and III– VIII with 1+1 bristlecombs. Coxites IX in both sexes with transverse bristlecombs across the inner process. One pair of styli only ( IX). Parameres absent. Penis typical for family; large, two segmented, apically with many short glandular setae each set on a protuberance. Cerci with both broad and lanceolate scales .

Female, in the one species where it is known, with secondary type ovipositor with apical spines.

Etymology. The genus is close to Acrotelsella Silvestri but carries only half the number of styli. The name is composed of the Greek prefix “hemi” meaning half combined with— telsella. It is treated as grammatically feminine.

Remarks. Short transverse combs on coxites IX have previously been reported for several species of Ctenolepisma (Sceletolepisma) Wygodzinsky, 1955 sensu Irish, 1987 including C. albid a Escherich, 1905, C. guadianica Mendes, 1992 , C. maroccana Mendes, 1980 , C. serranoi Mendes, 1985 , C. silvestrii Stach, 1946 , C. luederitzi, Irish, 1987 , C. namibensis Irish, 1987 , C. placida Irish, 1987 and C. spinipes Irish, 1987 . Several of these species are not that different to species of Ctenolepisma (Sceletolepisma) without such combs (Mendes pers. comm.) and hence the presence of such combs may not be of high taxonomic importance. In the case of Hemitelsella , these combs are much more substantial and the inner processes of the coxites quite wide rather than elongated. Hemitelsella would appear to be closely related to Acrotelsella Silvestri with which it shares the same dorsal chaetotaxy and shape of urotergite X, however in the chaetotaxy of the head, the rounded tipped setae on the tarsi and the sensillae of the distal antennal intervals it would appear to be closer to species of Qantelsella Smith, 2015 .

Figures

Figures 164–177. Hemitelsella clarksonorum n.sp. holotype ♂ (164) habitus, with loose antennae drawn as if attached; (165) smooth, apically bifurcate seta of prementum; (166) pectinate macrochaetae of coxa of PIII; (167) round-tipped macrochaeta from apex of tibia of PIII; (168) darker scale from face of pronotum; (169) darker scale from margin of pronotum; (170) hyaline scale from mesonotum; (171) head (cross-hatched area obscured by eye pigment; (172) antenna, scape, pedicel and basal intervals of flagellum (graphically reconstructed joining loose antennae to scape); (173) idem, most distal surviving interval showing poculiform sensillae (ps); (174) mandible; (175) idem, incisor and molar regions; (176) maxilla, smaller setae omitted; (177) idem, ultimate article of palp showing possible poculiform sensilla (ps?) and thin-walled sensilla (tws). Scale bars = 0.1 mm unless otherwise indicated.