Siobla plesia Malaise, 1945

Niu, Gengyun & Wei, Meicai, 2021, Review of some Siobla (Hymenoptera: Tenthredinidae) species, Zoological Systematics 46 (3), pp. 208-224 : 218

Siobla plesia Malaise, 1945 stat. nov. ( Figs 11–13 )

Siobla sturmii plesia Malaise, 1945: 127 . Type locality: Sichuan, China.

Diagnosis. This species is similar to S. yunanensis , but differs from the latter by the following: mesoscutellum flat. Female: basal three antennomeres with black spots, abdominal sternites yellowish brown; Male: dorsum of flagellum without black stripe, posterior margin of pronotum reddish brown, outer of basal fumer of the hind leg with reddish spot, abdominal sternites reddish brown.

Distribution. China (Sichuan (Ganzi)).

Primary type examined. 1♀, Lectotype ( USNM, here designated): “ 9 mi. SW of Tatsienlu, Jun 25–7.23, 8500–13000ft ”; “Szechuen CHINA DCGraham”; “Type No. 27440, USNM ”; “ S. sturmii (Kl) , var. plesia n.var. Malaise det. 1936”; “ Siobla plesia , TYPE. Roh.”. 1♂, paralectotype ( USNM, here designated): “ 9 mi. SW of Tatsienlu, Jun 25–7.23, 8500–13000ft ”; “Szechuan CHINA DC Graham”; “Type No. 27440, USNM ”; “ S. sturmii (Kl) , var. plesia n. var. Malaise det. 1936”; “ Siobla plesia , allotype. Roh.”.

Other material examined. 1♀ 1♂, Maiba, Kangding , Sichuan, E101º34.856′, N30º03.631′, 3525 m, 2009-VII-01, Wei Meicai ; 1♀ 1♂, China, Kangding , 2800 m, Sichuan Prov. 18.VI.1990, F. S. Naito leg., F.S.Huang leg.; Exchange KUK ; 1♀ 1♂, China, Mt. Zheduoshan 3100 m, Sichuan Prov. 21.VI.1990. M. T. Naito leg. M. Takeda leg.; Exchange KUK .

Remarks. Malaise (1945) reported plesia as a subspecies of S. sturmii (Klug, 1817) . Here we treat plesia as an independent species as it is distinct from S. sturmii .

In S. sturmii , the female has following characters: abdominal tergites 2–4 and tergite 9 yellowish brown; pale margin of pronutum narrow; hairs on head and thorax brown; hind tarsi somewhat dark; the male abdominal tergites 2–3 yellowish brown; sternites 5–7 and basal plate black; the female lancet more slender with sharper serrulae, the area below pore line (aso of Ross, 1945) quite narrow and bent, dorsal margin round ( Figs 13f, h ); the inner margin of male harpe weakly incised ( Fig. 13j ); the dorsal margin of the valviceps convex above middle ( Fig. 13l ).

In S. plesia , the female has follwing characters different from S. Sturmii : abdominal tergites 2–5, and tergites 7–9 yellow ( Figs 11a–c ); pale margin of pronutum broad ( Fig. 13c ); hairs on head ( Figs 12a, c, e ) and thorax ( Figs 13a, c ) yellowish brown; hind tarsi yellow ( Figs 11a–c ); the male abdominal tergites 2–4 yellowish brown; sternites 5–7 and basal plate yellow with dark macula ( Figs 11e–g ); the female lancet less slender with obtuse serrulae, the area below pore line broad and not bent, dorsal margin almost truncate ( Figs 13e, g ); the inner margin of male harpe weakly convex ( Fig. 13i ); the dorsal margin of the valviceps convex below middle ( Fig. 13k ).

Figures

Figure 11. Siobla plesia Malaise, 1945. a–d. Lectotype of S. sturmii plesia Malaise, 1945, ♀. e–h. Paralectotype of S. sturmii plesia Malaise, 1945, ♂. a. Dorsal view. b–c. Lateral view. d. Labels. e. Dorsal view. f–g. Lateral view. h. Labels. Scale bars=1mm.

Figure 12. Siobla plesia Malaise, 1945, head, same specimens as Figure 11. a–b. Dorsal view. c–d. Frontal view. e–f. Lateral view. a, c, e. Lectotype of S. sturmii plesia Malaise, 1945, ♀. b, d, f. Paralectotype of S. sturmii plesia Malaise, 1945, ♂. Scale bars=1mm.

Figure 13. Siobla spp. a–b. Thorax in lateral view. c–d. Thorax in dorsal view. e–f. Lancet. g–h. Middle serrulae. i–j. Gonoforcep. k–l. Penis valve. a, c, e, g. Lectotype of S. sturmii plesia Malaise, 1945, ♀. b, d, f, h. Nontype of S. sturmii (Klug, 1817), ♀. i, k. Nontype of S. sturmii plesia Malaise, 1945, ♂. j, l. Nontype of S. sturmii (Klug, 1817), ♂. Scale bars=1mm.