Aposthonia guizhouensis Chen 2022, sp. nov.
Creators: name: Chen, Zhi-Teng
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Embioptera
Oligotomidae
Aposthonia
Aposthonia guizhouensis

description: Aposthonia guizhouensis sp. nov.
Figs. 1–9
Type material. Holotype male, (ICJUST) China: Guizhou Province, Guiyang City, Guiyang Forest Park, 26.5499891° N, 106.766504° E, 1100 m, 6-VI-2019, Lu Qiu. Paratypes: four males and four females, same locality and data as holotype (ICJUST).
Etymology. The species is named after the type locality, Guizhou Province.
Distribution. This species is known only from Guiyang Forest Park, Guizhou Province, China.
Description
Alate male (n = 5). Head length 1.5–2.0 mm, width 0.9–1.2 mm; body length 10.0–11.0 mm, width 0.8–1.0 mm; forewing length 6.5–8.0 mm, hindwing length 6.5–7.0 mm. Head capsule dark brown (Figs. 1–3), near 1.5 times longer than broad with kidney-shaped small eyes, sides behind eyes near parallel, gradually converging posteriorly. Clypeus pale and near trapezoidal (Fig. 3A). Labrum membranous posteriorly and laterally, anteriorly with a dark brown, elliptical sclerite (Fig. 1). Maxillary palpi brown, five-segmented; labial palpi brown and short, threesegmented (Figs. 2, 3B). Submentum brown, near rectangular, with medial concave at both anterior and posterior margins, posterior corners slightly projected laterad (Fig. 3B). Mandible dark brown. Antennae brown throughout, at least 21-segmented (Figs. 1–2). Prothorax dark brown (Fig. 1), much shorter and narrower than head, near quadrate with subqual length and width, surface with deep transverse and longitudinal grooves; meso- and metathorax generally brown with dark margins. Wings brown with longitudinal pale stripes (Figs. 1–2); anterior medial vein (MA) not forked. All legs dark brown except the pale articulations. Hind leg with only one basitarsal papilla (Fig. 2).
Abdomen brown throughout with terminalia darker. Terminalia with left (10L) and right (10R) hemitergites of segment 10 of relatively equal size (Figs. 4A, B). Process of 10L (10LP) sickle-shaped, subapically with a triangular spine pointing laterad (Figs. 4A–D); process of 10R (10RP) slightly wider and much longer than 10LP, inner margin dentate, apex pointed and curved laterad (Figs. 4A–D); epiproct (EP) sclerotized, length ca. two times longer than width, with concave lateral margins and rounded posterior margin (Figs. 4A–B). Hypandrium (H = sternite 9) broad and rounded (Figs. 4C–D). Process of H (HP) broad and near trapezoidal. Left paraproct (LPPT) broad, sclerotized, acutely pointed and hooked posterolaterally (Figs. 4A–D). Left cercus-basipodite (LCB) less developed, forming a brown plate at base of left cercus. Basal segment of left cercus (LC 1) dilated distally and slightly lobed without echinulation (Figs. 4A–D).
Apterous female (n = 4). Head length 1.5–2.0 mm, width 1.0– 1.2 mm; body length 11.0–12.0 mm, width 1.2–1.5 mm. Head capsule dark (Fig. 5A–B), convex, slightly longer than wide. Eyes dark, smaller than in male. Submentum rectangular (Fig. 5B). Antennae with at least 22 segments, basal 14–17 segments brown, distal segments pale (Figs. 5A–B). Prothorax entirely pale; meso- and metathorax generally brown. Foreleg with pale femur, tibia and pale brown apical two tarsal segments; tibia of mid leg and hind leg with both ends conspicuously pale (Figs. 5A–B). Hind leg with only one basitarsal papilla (Figs. 5B). Abdomen brown throughout, similar to meso- and metathorax. Tenth tergum elongated posteriorly (Fig. 6A); tenth sternum symmetrically divided longitudinally into two lateral plates (Fig. 6B). Cerci entirely dark brown (Figs. 5A–B).
DNA barcode. The obtained COI sequence of A. guizhouensis sp. nov. was 678 bp in length. The genetic distance between A. guizhouensis sp. nov. and all other sequenced congeners is a high value of over 0.2 (Fig. 7A), which excludes its identity with these congeners. The NJ and ML trees generated very similar tree topology (Figs. 7B–C), where A. guizhouensis sp. nov. clustered with an unidentified species from Mexico, Aposthonia sp. KBMEB165 (accession No. JQ907087). However, the high sequence divergence (0.2) and the remarkable geographical isolation exclude conspecific status of the two species.
Remarks. The new species is assigned to genus Aposthonia instead of Oligotoma or Eosembia on the basis of the following combination of characters: absence of mesal lobing of the left cercus-basipodite (LCB) in the male; hind basitarsus with single ventral papilla in both male and female (Ross 2007, Poolprasert et al. 2011a, b). The presence of an outer subapical spine on 10LP in combination with the apically pointed and out-curved 10RP can easily separate A. guizhouensis sp. nov. from all other species of Aposthonia (Poolprasert et al. 2011a). The new species can be distinguished from A. borneensis, the only known Aposthonia species from China, by the small eyes, different shapes of 10LP, 10RP, HP and LPPT in the male and by the apparently different body color in the female (see Figs. 2–3 in Poolprasert et al. 2011a). The DNA barcode of A. guizhouensis sp. nov. also exhibits a high ratio of sequence divergence from all included sequences of A. borneensis (Fig. 7A), strongly supporting A. guizhouensis sp. nov. as a distinct different species from A. borneensis.
Aposthonia guizhouensis sp. nov. is common in Guiyang Forest Park, inhabiting various habitats from dirt road in wild jungle (Figs. 8A–C) to man-made stone railings and columns (Figs. 9A–C). There are also numerous examples of adults of A. guizhouensis sp. nov. in Guiyang City. Their abundance is evidence that Guiyang City is a warm area with a high humidity and plenty of vegetable matter such as dead leaves and lichens. The Embioptera fauna in China lacks systematic investigation and is apparently underestimated. More undescribed webspinners are expected to be discovered in this vast area.
description: Published as part of Chen, Zhi-Teng, 2022, Aposthonia guizhouensis sp. nov., a new webspinner of Oligotomidae (Insecta: Embioptera) from China, pp. 190-198 in Zootaxa 5213 (2) on pages 191-194, DOI: 10.11646/zootaxa.5213.2.7, http://zenodo.org/record/7354432