Chelonus (Stylochelonus), Hellen, 1958

Zhou, Jin-Jin, Achterberg, Cornelis Van, Tang, Pu & Chen, Xue-Xin, 2024, A review of the subgenera Carinichelonus, Microchelonus, Parachelonus and Stylochelonus of the genus Chelonus Panzer (Braconidae: Cheloninae) with descriptions of twenty-one new species from China, Zootaxa 5412 (1), pp. 1-127 : 113-114

Subgenus Stylochelonus Hellén, 1958

Diagnosis. Head transverse; antennomeres of both sexes more than 16, often distinctly widened medially in females; eye densely setose; frons and vertex very coarsely rugose; face flat, either striate-rugose or reticulate-rugose; clypeus often finely punctate, with distinct setosity and shiny; mesoscutum and scutellum evenly convex, densely alveolate-rugose; propodeum coarsely rugose; vein 1-SR+M of fore wing absent; hind coxa, femur and apex of tibia distinctly robust; metasomal carapace of male with small apical opening, which may be filled by point-like sclerite; carapace of female usually with an apical tooth; carapace apically usually rounded in dorsal view, rarely narrowed posteriorly.

Biology. Parasitoids of Elachistidae and Tortricidae ( Yu et al. 2016) .

Distribution. Worldwide ( Yu et al. 2016).

Key to species of subgenus Stylochelonus Hellén, 1958

1 Females............................................................................................. 2

- Males............................................................................................. 14

2 Carapace of female without an apical tooth in dorsal view ( Fig. 102E )........................................... 3

- Carapace of female with an apical tooth in dorsal view ( Fig. 106E ).............................................. 4

3 Temples strongly narrowed behind eyes in dorsal view; head 2.5 × wider than long in dorsal view ( Fig. 102G ); legs dark ( Fig. 101 )............................................................................. C. ( S.) acaretrus sp. nov.

- Temple almost parallel-sided behind eyes in dorsal view; head 1.6 × wider than long in dorsal view; legs pale...................................................................................... C. ( S.) interpositus ( Tobias, 1995)

4 Legs pale or yellowish brown ( Fig. 105 )................................................................... 5

- Legs dark brown or black............................................................................... 9

5 Temples distinctly widened behind eyes in dorsal view; [vein 1-R1 of fore wing shorter than pterostigma]............... 6

- Temples parallel-sided or slightly narrowed behind eyes in dorsal view ( Fig. 106G )................................. 7

6 Length of 3 rd antennomere 4.0 × its width; mesosoma 1.3 × longer than high in lateral view................................................................................................. C. ( S.) mucronatus ( Thomson, 1874)

- Length of 3 rd antennomere 3.0 × its width; mesosoma 1.7 × longer than high in lateral view. C. ( S.) pedator ( Dahlbom, 1833)

7 Vein 1-R1 of fore wing shorter than pterostigma; vein r of fore wing straight ( Fig. 106A )...... C. ( S.) punctulosus sp. nov.

- Vein 1-R1 of fore wing as long as or longer than pterostigma; vein r of fore wing curved............................. 8

8 Mesosoma 1.5 × longer than high in lateral view; face 2.0 × wider than high............ C. ( S.) pusillus ( Szépligeti, 1908)

- Mesosoma 1.7 × longer than high in lateral view; face 1.5 × wider than high............. C. ( S.) elachistae ( Tobias, 1995)

9 Temples distinctly widened behind eyes in dorsal view....................................................... 10

- Temples parallel-sided or slightly narrowed behind eyes in dorsal view.......................................... 12

10 Vein 1-R1 of fore wing longer than pterostigma; penultimate antennomere shorter than wide.. C. ( S.) koponeni ( Tobias, 1995)

- Vein 1-R1 of fore wing as long as or shorter than pterostigma; penultimate antennomere as long as wide or longer....... 11

11 Penultimate antennomere as long as wide; antennomeres of female 21–22................ C. ( S.) karadagi ( Tobias, 1995)

- Penultimate antennomere longer than wide; antennomeres of female 23................ C. ( S.) subpedator ( Tobias, 1995)

12 Posterior excavation of head deep; antennomeres of female 17; sculpture at base of carapace reticulate-rugose................................................................................ C. ( S.) septemdecimplex ( Tobias, 1986)

- Posterior excavation of head shallow; antennomeres of female 20; sculpture at base of carapace longitudinally rugose................................................................................ C. ( S.) magadani ( Tobias, 1994)

14 Carapace of male with an apical tooth in dorsal view ( Fig. 108E )......................... C. ( S.) punctulosus sp. nov.

- Carapace of male without an apical tooth in dorsal view ( Fig. 104E )............................................ 15

15 Fifth-ninth antennomeres of male yellow and more distal antennomeres brown; antenna clearly widened beyond middle ( Fig. 104I ); [vein r of fore wing slightly curved ( Fig. 104A ); temples narrowed behind eyes in dorsal view ( Fig. 104H )]......................................................................................... C. ( S.) acaretrus sp. nov.

- Fifth-ninth antennomeres of male brown or dark brown as more or less distal antennomeres......................... 16

16 Legs pale or yellowish brown........................................................................... 17

- Legs dark brown or black.............................................................................. 19

17 Temples distinctly widened behind eyes in dorsal view; vein 1-R1 of fore wing shorter than pterostigma........................................................................................... C. ( S.) pedator ( Dahlbom, 1833)

- Temples parallel-sided or slightly narrowed behind eyes in dorsal view; vein 1-R1 of fore wing as long as pterostigma or longer............................................................................................. 18

18 Mesosoma 1.5 × longer than high in lateral view; metasomal carapace 2.0 × longer than wide in dorsal view....................................................................................... C. ( S.) interpositus ( Tobias, 1995)

- Mesosoma 1.7 × longer than high in lateral view; metasomal carapace 1.8–1.9 × longer than wide in dorsal view.................................................................................... C. ( S.) elachistae ( Tobias, 1995)

19 Apical aperture of carapace in posterior view large, occupying about 0.3 of carapace width.......................... 20

- Apical aperture of carapace in posterior view occupying 0.1–0.2 of carapace width................................ 21

20 Face narrow, about 1.6 × wider than high; mesosoma 1.5 × longer than high in lateral view.. C. ( S.) lissofossa ( Tobias, 2000)

- Face about 2.0 × wider than high; mesosoma 1.3 × longer than high in lateral view...... C. ( S.) cariniventris ( Tobias, 1996)

21 Apical aperture located in upper half of posterior part of metasomal carapace and oblique to horizontal plane; [vein 1-R1 of fore wing shorter than pterostigma; mesosoma 2.0 × longer than high in lateral view]............ C. ( S.) elongatus ( Papp, 1971)

- Apical aperture located in middle of posterior face of metasomal carapace and in vertical plane...................... 22

22 Vein 1-R1 of fore wing longer than pterostigma; [mesosoma 2.0 × longer than high in lateral view; apical aperture in posterior view occupying about 0.2 of metasomal carapace width].............................. C. ( S.) koponeni ( Tobias, 1995)

- Vein 1-R1 of fore wing as long as pterostigma or shorter..................................................... 23

23 Vein r of fore wing shorter than vein 3-SR; [antennomeres of male 23; apical aperture in posterior view occupying 0.18–0.23 of metasomal carapace width]................................................... C. ( S.) karadagi ( Tobias, 1995)

- Vein r of fore wing longer than vein 3-SR................................................................. 24

24 Face about 3.0 × wider than high; [antennomeres of male 25; mesosoma 1.5 × longer than high in lateral view]........................................................................................ C. ( S.) clausus ( Tobias, 1996)

- Face less than 2.0 × wider than high..................................................................... 25

25 Length of 3 rd antennomere 4.0 × its width; mesosoma 1.3 × longer than high in lateral view................................................................................................. C. ( S.) mucronatus ( Thomson, 1874)

- Length of 3 rd antennomere less than 3.5 × its width; mesosoma more than 1.5 × longer than high in lateral view......... 26

26 Face 2.0 × wider than high; metasomal carapace 1.8–1.9 × longer than wide in dorsal view..................................................................................................... C. ( S.) pusillus ( Szépligeti, 1908)

- Face 1.5 × wider than high; metasomal carapace 2.0–2.2 × longer than wide in dorsal view.................................................................................................... C. ( S.) subpedator ( Tobias, 1995)

Figures

FIGURE 101. Chelonus (Stylochelonus) acaretrus sp. nov., female, holotype, habitus, lateral aspect.

FIGURE 102. Chelonus (Stylochelonus) acaretrus sp. nov., female, holotype. A, fore wing; B, mesosoma, lateral aspect; C, mesosoma, dorsal aspect; D, metasoma, lateral aspect; E, metasoma, dorsal aspect; F, head, anterior aspect; G, head, dorsal aspect; H, head, lateral aspect.

FIGURE 104. Chelonus (Stylochelonus) acaretrus sp. nov., male, paratype. A, fore wing; B, mesosoma, lateral aspect; C, mesosoma, dorsal aspect; D, metasoma, lateral aspect; E, metasoma, dorsal aspect; F, metasoma, posterior aspect; G, head, anterior aspect; H, head, dorsal aspect; I, antenna; J, head, lateral aspect.

FIGURE 105. Chelonus (Stylochelonus) punctulosus sp. nov., female, holotype, habitus, lateral aspect.

FIGURE 106. Chelonus (Stylochelonus) punctulosus sp. nov., female, holotype. A, fore wing; B, mesosoma, lateral aspect; C, mesosoma, dorsal aspect; D, metasoma, lateral aspect; E, metasoma, dorsal aspect; F, head, anterior aspect; G, head, dorsal aspect; H, head, lateral aspect.

FIGURE 108. Chelonus (Stylochelonus) punctulosus sp. nov., male, paratype. A, fore wing; B, mesosoma, lateral aspect; C, mesosoma, dorsal aspect; D, metasoma, lateral aspect; E, metasoma, dorsal aspect; F, metasoma, posterior aspect; G, head, anterior aspect; H, head, dorsal aspect; I, antenna; J, head, lateral aspect.