Trichadenotecnum sibolangitense Endang & New
Creators: name: Yoshizawa, Kazunori
name: Lienhard, Charles
name: Abd, Idris
Publisher: name: Zenodo
Year: 2014
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Psocodea
Psocidae
Trichadenotecnum
Trichadenotecnum sibolangitense

description: Trichadenotecnum sibolangitense Endang & New
(Figs 1N, 18, 19)
Trichadenotecnum sibolangitense Endang & New, 2005: 27.
Specimens examined. [Malaysia] 1 female, Gunung Jasar, Cameron Highlands, Pahang, 14.iii.2003, KY; 1 male (KY345) Gunung Berembun, Cameron Highlands, Pahang, 10.iii.2005, NT. [Singapore] 1 female, Botanic Gardens, Forest (low foliage), 6.xi.1981, DHM (MHNG).
Description of female genitalia. Egg guide (Fig. 19A) short, shorter than basal width, ventrally membranous and dorsally widely sclerotized, distal margin concave; body of subgenital plate broadly sclerotized, anteromedially with wide membranous region, posterior margin with pair of long, narrow and sharply pointed lateral processes. Gonapophyses (Fig. 19B). Ventral valve not exceeding external valve; dorsal valve broad, with deep pouch posteromedially, distal process long; external valve with broad membranous region anteriorly and with flap-like expansion posteriorly, posterior lobe broad, internal lobe narrow. Spermapore plate (Fig. 19C) symmetrical, pigmented around spermapore.
Remarks. This species was originally described from Sumatra, Indonesia based on a single male and is here recorded from Peninsula Malaysia for the first time. The male specimens examined here agree exactly with the original description except for the hypandrial structures being in mirror image (Fig. 18C). Given the exact similarity of each structure, we concluded that the illustration of the hypandrium of this species presented in Endang & New (2005) is drawn in dorsal (internal) view or reproduced in reversed position. This species is apparently closely related to T. alinguum Endang, Thornton & New, 2005 and, in T. sibolangitense, the right side of the hypandrium is strongly expanded, as illustrated in Fig. 18C. Given the lack of the hypandrial median tongue and the triangular shape of the hypandrium, this species is considered to be closely related to T. arciforme (Thornton, 1961; Yoshizawa & Lienhard, 2004). In contrast, these species are clearly different in the condition of the epiproct: strongly expanded over the clunium in T. sibolangitense (Fig. 18A) whereas almost flat and covered by the clunial flap in T. arciforme. The state as observed in T. arciforme is unique even among the tribe Ptyctini, in which Trichadenotecnum is classified. Because of this highly unusual feature, Yoshizawa & Lienhard (2004) did not assign T. arciforme to any species group, although they pointed out that T. arciforme is possibly closely related to T. apertum. The strongly expanded epiproct as observed in T. sibolangitense and similarities of the hypandrial structure between this species and T. arciforme corroborate the idea that T. arciforme (hypandrial median tongue absent and ventral valve of gonapophyses short) is closely related to T. apertum and its relatives, and that the highly specialized condition of the epiproct-clunium interface has to be considered as an autapomorphy of T. arciforme.
The female of T. sibolangitense is described here for the first time. As shown in Fig. 19A, it is characterized by possession of a pair of sharp processes arising from the posterior margin of the subgenital plate. Similar structures have been reported from some species such as T. suwai Yoshizawa & Lienhard, 2007 from Nepal or T. laticornutum Endang et al., 2002 and T. waykananense Endang & New, 2005 from Indonesia. The former species is phylogenetically distant (belonging to the spiniserrulum group) from T. sibolangitense so that presence of these processes can be recognized as convergence. In contrast, although the species-group assignments of T. laticornutum and T. waykananense have not been proposed in the original descriptions (Endang et al., 2002; Endang & New, 2005), their close affinity with T. sibolangitense is very likely.
description: Published as part of Yoshizawa, Kazunori, Lienhard, Charles & Abd, Idris, 2014, Trichadenotecnum species from Peninsular Malaysia and Singapore (Insecta: Psocodea: ' Psocoptera': Psocidae), pp. 469-500 in Zootaxa 3835 (4) on pages 487-488, DOI: 10.11646/zootaxa.3835.4.3, http://zenodo.org/record/4921623