Chelonus (Megachelonus) Baker 1926
Creators: name: Ranjith, A. P.
name: Priyadarsanan, Dharma Rajan
Publisher: name: Zenodo
Year: 2023
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hymenoptera
Braconidae
Chelonus

description: Subgenus Megachelonus Baker, 1926
(Figures 6–15)
Diagnosis. Head transverse (Figs 6B–C, 8B–C, 10B, E, 14B–C); antennomeres of apical half broadened or same width (Figs 6A, 13B); face striate (Figs 6B, 10B, 14B) or reticulate-rugose (Fig. 8B); clypeus semi-elliptical (Figs 6B, 8B, 10B, 14B); eyes long elliptical or ovoid in lateral view (Figs 10F, 14D); frons rather concave (Figs 6C, 8C, 10E, 14C); vertex and occiput reticulate rugose (Fig. 8C) or striate-rugose (Figs 6C, 10E, 14C); mesoscutum reticulate-rugose (Figs 6E, 8E, 11B, 13B, 14F); notauli impressed or not (Figs 6E, 8E, 11B, 13B, 14F); scutellum punctate (Figs 6E–F, 11B, 13B, 14F) or coarsely sculptured (Figs 8E–F); propodeum coarsely rugose (Figs 6F, 8F, 15A), rarely with triangular areola medio-basally (Figs 11C–D); propodeum often with medial and lateral tubercles (Figs 6F, 8F), rarely without tubercles (Figs 11C–D, 15A); fore wing vein SR1 complete (Figs 7D, 9D, 13A, 15F); metasomal carapace often with lamellae laterally (Figs 8A, 9A, 15B, D), rarely not (Fig. 11E); carapace with a pair of short (Figs 7C, 9C, 12A) to long teeth medio-apically (Figs 15C, E).
Biology. Unknown.
Distribution. Oriental region.
Key to the species of subgenus Megachelonus Baker
1. Metasomal carapace broadly yellowish basally (Figs 11F, 13B, 15C)............................................. 2
- Metasomal carapace completely black (Figs 7A, B, 9A, B).................................................... 8
2. Apex of carapace with a pair of long teeth (Figs 15C, E)...................................................... 3
- Apex of carapace with a pair of short to small teeth (Figs 7C, 9C, 12A).......................................... 4
3. Female with 28 antennomeres; carapace yellowish basally and baso-laterally; OOL 1.5 × POL; propodeum with large lateral tubercles............................................ C. (M.) macrodontus Zhou, van Achterberg, Tang & Chen
- Female with 16 antennomeres (Fig. 14A); carapace with two large yellowish spots laterally (Fig. 15C); OOL 1.1 × POL; propodeum with indistinct blunt lateral tubercles (Figs 14E, 15A)........................ C. (M.) sahyadriensis sp. nov.
4. Metasomal carapace without lateral lamellae (Fig. 11E)....................................................... 5
- Metasomal carapace with lateral lamellae (Figs 8A, 9A)...................................................... 6
5. Propodeum with lateral tubercles; scutellum rugose; notauli indistinct; carapace without a pair of posteriorly narrowing longitudinal carinae.................................... C. (M.) irilaminatus Zhou, van Achterberg, Tang & Chen
- Propodeum without lateral tubercles (Figs 11A, C–D); scutellum punctate (Figs 11B, 13B); notauli distinct (Fig. 11B); carapace with a pair of posteriorly narrowing longitudinal carinae (Fig. 11F)............................. C. (M.) novis sp. nov.
6. Metasomal carapace entirely yellowish basally; ventral cavity reaching apex of carapace......... C. (M.) bidentatus Baker
- Metasomal carapace with large yellowish spots basally; ventral cavity reaching 1/4 th of carapace apically................ 7
7. Metasomal carapace with long and wide ventral lamellae; third antennomere 5.6 × as long as wide; scutellar sulcus divided by six carinae; fore wing vein 2-CU1 2.0 × as long as 1-CU1........................ C. (M.) macros Zhang, Chen & He
- Metasomal carapace with short and narrow ventral lamellae; third antennomere 4.6 × as long as wide; scutellar sulcus divided by four carinae; fore wing vein 2-CU1 3.4 × as long as 1-CU1.................. C. (M.) longqiensis Zhang, Chen & He
8. Metasomal carapace with a strongly transverse depression dorsally; antenna with more than 19 antennomeres.......................................................................................... C. (M.) rectangularis Baker
- Metasomal carapace without a strongly transverse depression dorsally (Figs 6B, 8B); antenna with 16 antennomeres...... 9
9. Hind coxa black; hind femora brown apically; body length 6.0 mm........................ C. (M.) bicoloricomis Baker
- Hind coxa yellow to reddish yellow (Figs 7A, 9A); hind femora yellow to reddish yellow (Figs 7A, 9A); body length 2.2–3.2 mm ............................................................................................... 10
10. Metasomal carapace 1.8 × as long as wide; hind tibia reddish yellow.......................... C. (M.) uniformis Baker
- Metasomal carapace more than 1.8 × as long as wide (Figs 7B, 9B); hind tibia black basally and apical half (Figs 7A, 8A). 11
11. Face transversely striate-rugose (Fig. 6A); scutellum punctate, divided with five carinae (Fig. 6E); metasomal carapace with a pair of longitudinal carinae basally (Fig. 7B); vertex transversely striate (Fig. 6C)................... C. (M.) adii sp. nov.
- Face reticulate-rugose with midlongitudinal carina (Fig. 8B); scutellum rugose with Y shaped carina, divided with four carinae (Fig. 8E); metasomal carapace without a pair of longitudinal carinae basally (Fig. 9B); vertex reticulate-rugose (Fig. 8C)................................................................................. C. (M.) biligiriensis sp. nov.
description: Published as part of Ranjith, A. P. & Priyadarsanan, Dharma Rajan, 2023, New subgeneric reports of the genus Chelonus (Hymenoptera: Braconidae) from India and Sri Lanka with description of nine species, pp. 461-492 in Zootaxa 5278 (3) on pages 470-471, DOI: 10.11646/zootaxa.5278.3.3, http://zenodo.org/record/7906532