Davidius davidii yunnanensis Yang & Davies, 1996
|
publication ID |
https://doi.org/10.11646/zootaxa.5633.3.10 |
|
publication LSID |
lsid:zoobank.org:pub:B4947435-B9C7-4F0C-B6EC-A9A13E1387CA |
|
DOI |
https://doi.org/10.5281/zenodo.15463162 |
|
persistent identifier |
https://treatment.plazi.org/id/03D187F8-FF98-FFEF-4997-5156FEE2F872 |
|
treatment provided by |
Plazi |
|
scientific name |
Davidius davidii yunnanensis Yang & Davies, 1996 |
| status |
|
Davidius davidii yunnanensis Yang & Davies, 1996 View in CoL
( Figs 2a–n View FIGURE 2 ; 3c–d View FIGURE 3 ; 4c–e View FIGURE 4 ; 5b View FIGURE 5 )
Material examined
2 ♂♂ larvae, 2 ♀♀ larvae, 26. III. 2021, Xueshanhe Stream (25.69°N, 100.04°E, 2272 m a.s.l), Yangbi Town, Dali City, Yunnan Province, China, Guo-Hui Yang leg. GoogleMaps , 1 ♂ F-0, adult emergence 10. IV. 2021 ; 1 ♂ larva, 2 ♀♀ larvae, 19. III. 2022, Luopingshan Stream (26.00°N, 99.90°E, 2673 m a.s.l), Fenyu Town, Dali City, Yunnan Province, China, Guo-Hui Yang leg. GoogleMaps , 1 ♀ F-0, adult emergence 16. IV. 2022 , 1 ♀ F-0, adult emergence 18. IV. 2022 . Of these, 1 ♂, 2 ♀♀ larvae were successfully reared to adult in the laboratory.
Description
Moderately sized (18–23 mm length), body brown ( Figs. 2a View FIGURE 2 ; 4c View FIGURE 4 ), flattened, lateral spines present on S7–9 ( Figs. 2a, 2k; 2m –n View FIGURE 2 ), irregular dark in the living individual ( Fig. 4c View FIGURE 4 ).
Head. Mouthparts very similar to D. zallorensis ( Fig 2 View FIGURE 2 ), but head 2.0 times as wide as long. Occipital margin protrusion small and not projecting laterally ( Figs. 2a View FIGURE 2 , 3c View FIGURE 3 ). The third segment of antennae longer than wide, about 1.6 times as long as wide, length of each segment (mm): 0.25, 0.26, 1.26, 0.10 ( Fig. 2b View FIGURE 2 ). Ligula with five distinct blackish–brown teeth in the middle; labial palp roundly-pointed and movable hook long, about 1.9 times as long as end hook ( Fig. 2c–d View FIGURE 2 ).
Thorax. Very similar to D. zallorensis but wing sheaths parallel, forewing sheaths reaching to 1/2 of S5, hindwing sheaths extending to 1/4 of S6; and hind femur extending to middle of S4.
Abdomen. Elliptical, widest at middle, maximum width on S5 ( Fig. 2k View FIGURE 2 ). Dorsal hooks absent, posterolateral spines present on S7-9 ( Figs. 2a, 2k View FIGURE 2 ). Paraprocts approximately 1.2 times longer than epiproct. Cerci short, 1/2 epiproct’s length ( Figs. 2n View FIGURE 2 , 3d View FIGURE 3 ). Male with small protuberances on supra-anal plate, slightly elevated upwards near lateral margins ( Fig. 3d View FIGURE 3 ). The marks of male accessory genitalia are visible ventrally at S2-3 ( Fig. 2l View FIGURE 2 ); female gonapophyses rudimentary, visible at posterior margin of S8 ( Fig. 2m View FIGURE 2 ).
Measurements (mm) Larvae (in alcohol, N=7). Total length (including caudal appendages) 18–23; length of abdomen (including caudal appendages) 12–15; maximum width of head 4–5; length of hind femur 3–5.
Habitat
The larvae of D. davidii yunnanensis were found in shallow mountain streams with high forest vegetation coverage. In the laboratory, they pushed the gravel on both sides of their bodies with their feet, hiding themselves inside and captured prey by sudden attacks. The adult males exhibit territorial behavior by perching on the rocks or plants near water in sunny days ( Figs. 4c–e View FIGURE 4 ; 5b View FIGURE 5 ).
Differential diagnosis
Davidius zhoui Chao, 1995 , D. davidii yunnanensis , D. zallorensis and Davidius sp. n. have been recorded from Erhai Lake Basin, Yunnan Province, China ( Yang et al. 2008; Zhang 2019).
Nine larvae of Davidius have been described. The larva of D. zallorensis differs from that of D. truncus by prementum widening from the 1/3 of basal and the widest of abdomen in S5 (prementum constricted in basal twothirds and the widest of abdomen in S 6 in D. truncus ); from that of D. fruhstorferi by occipital margin protrusion large, protruding more laterally and the widest of abdomen in S5 (occipital margin protrusion small, not projecting much laterally and the widest of abdomen in S 6 in D. fruhstorferi ); from that of D. davidii yunnanensis by four teeth on the apex of prementum and long lateral spine of S9, about 0.46 times lateral spine on S9/S9 ratio (five teeth on the apex of prementum and 0.21 times lateral spine on S9/S9 ratio in D. davidii yunnanensis ); from that of Davidius spec 1 by wing sheaths divergent and male with a pair of larger protuberances on the supra-anal plate, distinctly protruding backwards (wing sheaths parallel and male with a pair of small projections on the supra-anal plate, inconspicuous in lateral view in Davidius spec 1 ); from that of Davidius spec 2 by four teeth on the apex of prementum and male with a pair of larger protuberances on the supra-anal plate, distinctly protruding backwards (with fourteen teeth on the apex of prementum and male supra-anal plate has no visible protuberances in Davidius spec 2 ); from that of D. fujiama by occipital margin protrusion large, protruding more laterally and the third segment of antenna long, about 2.3 times as long as wide (occipital margin protrusion small not projecting much laterally and the third segment of antenna about 2.0 times as long as wide in D. fujiama ); from that of D. nanus by male with a pair of larger protuberances on the supra-anal plate, distinctly protruding backwards and the third segment of antenna long, about 2.3 times as long as wide (male with small protuberances on supra-anal plate, slightly elevated upwards near lateral margins and the third segment of antenna about 2.0 times as long as wide in D. nanus ); from that of D. moiwanus by male with a pair of larger protuberances on the supra-anal plate, distinctly protruding backwards and the widest of abdomen in S5 (male with a pair of small projections on the supra-anal plate, inconspicuous in lateral view and the widest of abdomen in S 6 in D. moiwanus ).
The larva of D. davidii yunnanensis with five teeth on ligula, it can be distinguished from other eight larvae of this genus.
No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.