Diplectrona Westwood, 1840

Zhou, Xin, 2009, The larvae of Chinese Hydropsychidae (Insecta: Trichoptera), Part I: Arctopsyche shimianensis, Parapsyche sp. A, and Diplectrona obscura, Zootaxa 2174, pp. 1-17 : 13

Genus Diplectrona Westwood, 1840

Diplectrona is the only genus of the subfamily Diplectroninae occurring in China ( Yang et al. 2005). A total of six Diplectrona species are recorded from China. No Chinese Diplectorna larvae have been associated with their adults. Because the original species descriptions were overly simplified for most Chinese Diplectrona species and a significant portion of Chinese fauna remains unknown, many individuals used in this larvaladult association work were not identified to named species. However, the male genitalic structures of these morpho-species are distinctive. Thus, the species boundaries among the included Chinese Diplectrona species are clear.

LARVA— HEAD. Genae on ventral side of head touching along mid-ventral ecdysial line. Ventral apotome divided into anterior and posterior parts, posterior ventral apotome at least half as long as mid-ventral ecdysial line. Frontoclypeal apotome greatly constricted opposite eyes and strongly expanded after eyes. Foretrochantins not forked (in all Chinese Diplectrona species examined so far). Prosternal plate large, posterior prosternal sclerites absent. In dorsal view, pronotum slightly constricted at posterior end. Meso- and metanota each with transverse ecdysial lines. Lateral (pleural) gills on abdominal segments simple, fingerlike. Abdominal terga and pleura densely covered by hair-like setae and elongated club-hairs. Abdominal segment VII without ventral tracheal gills.

LARVAL-ADULT ASSOCIATION. In this work, 44 individuals of Diplectrona , representing 22 provisional species (HPGP 13–34, Fig. 1 ), were extracted for DNA amplifications ( Table 1 and Fig. 1 ). One possible association was made for Diplectrona obscura Ulmer, 1930 (represented by individuals CNCAD_0109, 0 110 and 0 177 in Table 1 and Fig. 1 ). The D2 sequence of the larval specimen (CNCAD_0177) is identical to the two adult D. obscura (0109 and 0110), while its COI is only 0.8% different from the latter two specimens. Although this larval form is very likely the larva of D. obscura , additional materials are needed to confirm this association. The two specimens representing HPGP 31 and 32 share identical D2 sequence but are distinctively separated in COI tree. This is likely due to the relatively slow evolving rate in D2.

Figures

FIGURE 1 a – b. Larval-adult association of Chinese Arctopsyche, Parapsyche, and Diplectrona — 1 a. COI neighborjoining phylogram; 1 b. D 2 neighbor-joining phylogram. Specimens are labeled with taxonomy, followed by sample ID (corresponding to Table 1) and province location. Specimens of immature life stage are noted at the end (pp: pharate pupa; lv: larva). COI tree is constructed in the BOLD system using Neighbor-joining and K- 2 - P parameter. D 2 tree is constructed in PAUP * 4.0 b 10 using Neighbor-joining and K- 2 - P parameter. Numbers on the internodes represent the bootstrap values using Neighbor-joining / 1000 replicates. Species boundaries recognized in morphology and two DNA sequences are marked in brackets on the right of each DNA tree and noted as haplogroups (HPGP) 1 - 34 respectively.