Cryptoperla pentagonalis Zwick & Sivec, 1980

Li, Hanyu & Li, Weihai, 2025, A new species and new record of Cryptoperla Needham, 1980 (Plecoptera: Peltoperlidae) from China, Zootaxa 5660 (2), pp. 273-278 : 276

Cryptoperla pentagonalis Zwick & Sivec, 1980

( Fig. 3 )

Cryptoperla pentagonalis Zwick & Sivec, 1980: 109

Cryptoperla pentagonalis : Stark 1989: 238

Cryptoperla pentagonalis : Chen 2020: 585

Supplementary description. Male ( Fig. 3 ). Body color dark brown ( Figs. 3a–c ). Body length 8.4 mm, forewing length 10.1 mm, hindwing length 8.9 mm (n=1). Sternum 9 rounded terminally, produced into a well-developed subgenital plate ( Figs. 3d–f ); vesicle present anteromedially, approximately as long as wide ( Fig. 3e ); two divergent arc lines extend to the posterior margin of vesicle, forming one median and two lateral areas ( Fig. 3e ). Basal cercal segment thin and long, ca. 5.3 X long as wide, inner margin with fringe of long setae, dorsal apex with a protuberance process ( Figs. 3d–f ). Tergum 10 with a posteromesal U-shaped sclerite; apex membranous ( Fig. 3d ). Aedeagus membranous, strongly ossified ( Figs. 3d–e ); apex divided into two petals with inner margins sclerotized, each basal petal with spines in ventral view ( Fig. 3e ); armature without dense, paired setal patches ( Figs. 3d–e ).

Material examined. Two males ( HIST); China: Xizang Autonomous Region, Motuo county , 29.2289° N, 95.1810° E, 1600 m, 2022.VIII.12, leg. Chuan Liu.

Remarks. There are two species of Cryptoperla distributed in the Himalayan region, C. pentagonalis and C. torva Needham, 1909 ( Zwick 1977; Zwick & Sivec 1980; Stark 1989). Cryptoperla pentagonalis differs from C. torva by the presence of a pentagonal sclerite on male tergum 10 with hairy areas and short cerci on nymphs ( Uchida & Isobe 1988). Cryptoperla pentagonalis is also similar to C. kumari Stark, 1989 from Assam, but the basal cercal segment of the former species is less than five times as long as the basal width, the aedeagus is armed with scattered fine setae, and the ventroapical aedeagal lobes are partially sclerotized ( Stark & Sivec 1999). In addition, the arrangement of setae of the male cerci of C. teana Li & Murányi, 2018 is most similar to C. pentagonalis . But, their everted aedeagi appear different: C. teana has more complex lobes and surface structures ( Li & Murányi 2018). For C. pentagonalis , its aedeagus has four apical lobes, a wide midventral depression, and the surface is covered with variably sized fine setae (figs. 9–12 in Stark & Sivec 1999).

In this study, we have discovered a new distributional record of C. pentagonalis from China (Motuo county, Xizang). Motuo is located along the lower Brahmaputra River at the southern slopes of Himalaya Mountains, which is a biodiversity hotspot of the Himalayas ( Myers et al. 2000). Due to its unique geographical location and topographic conditions, Motuo has a tropical rainforest climate with suitable temperature and abundant rainfall. The favorable ecological environment has endowed Motuo with abundant biodiversity. Besides, local microenvironmental differences lead to genetic and phenotypic adaptive variation in organisms ( Zhong et al. 2022; Jiang et al. 2023), and we need more samples to detect potential geographic-based population-level differences in the future.

Figures

FIGURE 3. Cryptoperla pentagonalis Zwick & Sivec, 1980, adult male. a: adult habitus, dorsal view. b: adult habitus, ventral view. c: head and pronotum, dorsal view. d: terminalia and aedeagus, dorsal view. e: terminalia and aedeagus, ventral view (red arrow points to vesicle). f: terminalia and aedeagus, lateral view.