Taxonomic revision of Bracalba Dodd (Hymenoptera, Platygastridae s.l.), a parasitoid wasp genus endemic to Australia

Abstract

The endemic Australian parasitic wasp genus Bracalba (Hymenoptera: Platygastridae) is revised. Sixteen species are recognized: Bracalba cuneata Dodd, Bracalba laminata Dodd and Bracalba nigrescens (Dodd) are redescribed and thirteen new species are recognized; Bracalba clavata Burks, sp. n., Bracalba globosa Burks, sp. n., Bracalba hesperia Burks, sp. n., Bracalba intermedia Burks, sp. n., Bracalba magnirubra Burks, sp. n., Bracalba parvirubra Burks, sp. n., Bracalba pinnula Burks, sp. n., Bracalba plana Burks, sp. n., Bracalba propodealis Burks, sp. n., Bracalba sculptifrons Burks, sp. n., Bracalba sparsa Burks, sp. n., Bracalba tricorata Burks, sp. n., and Bracalba tridentata Burks, sp. n. The genus is found continent-wide but mostly south of the Tropic of Capricorn, and with the highest species diversity occurring in the Pilbara and south-western regions of Western Australia. The hosts of Bracalba are unknown but specimens reared from eggs confirm that the genus is associated with orthopteran hosts. A preliminary phylogeny of species did not indicate that species groups were monophyletic, but they are retained despite paraphyly because they are convenient for specimen identification.

Keywords: Bracalba; Platygastridae s.l.; Platygastroidea; Scelionidae; Scelioninae; database; endemism; key; parasitoid; revision.

Figure 1.

Collection events for each Bracalba species. * = species known from only one locality.

Figure 2.

Strict consensus phylogram of two most parsimonious trees for species of Bracalba using implicit enumeration (branch-and-bound exact search), score = 166. Bootstrap support values found using TNT new technology search (set initial level = 95). Bremer support values above 1, and bootstrap values about 50% indicated on branches.

Figures 3–6.

Bracalba cuneata Dodd, holotype female (QMBA HY4733). 3 Dorsal habitus 4 Lateral habitus, female (OSUC 238135) 5 Head, anterior view 6 Metasomal sterna 5–6, ventral view. Morphbank¹⁵

Figures 7–11.

Bracalba globosa sp. n.,paratype female (OSUC 148612). 7 Lateral habitus 8 Head and mesosoma, dorsal view 9 Metasomal sterna 5–6, ventral view 11 Head, ventral view, holotype female (OSUC 148701) 10 Head, anterior view. Morphbank¹⁶

Figures 12–13.

Bracalba plana sp. n.,holotype female (OSUC 230804). 12 Dorsal habitus, paratype male (OSUC 148706) 13 Dorsal habitus. Morphbank¹⁷

Figures 14–18.

Bracalba clavata sp. n.,holotype female (OSUC 384555). 14 Dorsal habitus 15 Lateral habitus, paratype female (OSUC 384558) 16 Head, ventral view, paratype female (OSUC 384559) 17 Metasomal sterna 5–6, ventral view, paratype male (OSUC 384556) 18 Dorsal habitus. Morphbank¹⁸

Figures 19–23.

Bracalba hesperia sp. n.,holotype female (OSUC 148713). 19 Head and mesosoma, dorsal view 20 Head, ventral view 21 Lateral habitus; 22 Metasomal terga 5–6, dorsal view 23 Metasomal sterna 5–6, ventral view. Morphbank¹⁹

Figures 24–27.

Bracalba intermedia sp. n.,paratype female (OSUC 180713). 24 Dorsal habitus 25 Ventral habitus, paratype female (OSUC 148707) 26 Head, ventral view, paratype male (OSUC 227576) 27 Dorsal habitus. Morphbank²⁰

Figures 28–31.

Bracalba laminata Dodd, allotype male (QMBA HY4732A). 28 Head and mesosoma, dorsal view 29 Head, anterior view 30 Metasomal terga 6–8, posterior view, holotype female (QMBA HY4732H) 31 Antenna, ventral view. Morphbank²¹

Figures 32–35.

Bracalba magnirubra sp. n.,paratype female (OSUC 238178). 32 Dorsal habitus 34 Head, ventral view, holotype female (OSUC 148715) 33 Lateral habitus, paratype female (OSUC 238112) 35 Metasomal sterna 5–6, ventral view. Morphbank²²

Figures 36–39.

Bracalba nigrescens (Dodd) holotype male (B.M. TYPE HYM. 9.499). 36 Head and mesosoma, dorsal view 37 Metasomal terga 6–8, postero-lateral view 38 Head, anterior view 39 Head, ventral view. Morphbank²³

Figures 40–42.

Bracalba parvirubra sp. n.,holotype female (OSUC 238194). 40 Dorsal habitus 41 Lateral habitus 42 Ventral habitus. Morphbank²⁴

Figures 43–46.

Bracalba pinnula sp. n.,paratype female (OSUC 231794). 43 Dorsal habitus 45 Head, ventral view, holotype female (OSUC 231797) 44 Lateral habitus 46 Metasomal sterna 5–6, ventral view. Morphbank²⁵

Figures 47–50.

Bracalba propodealis sp. n.,holotype female (OSUC 227590). 47 Dorsal habitus, paratype female (OSUC 227591) 48 Lateral habitus, paratype female (OSUC 238190) 49 Head, ventral view 50 Metasomal sterna 5–6, ventral view. Morphbank²⁶

Figures 51–54.

Bracalba sculptifrons sp. n.,paratype female (OSUC 148704). 51 Dorsal habitus 53 Head, ventral view 54 Metasomal sterna 5–6, ventral view, holotype female (OSUC 231799) 52 Lateral habitus. Morphbank²⁷

Figures 55–59.

Bracalba sparsa sp. n.,holotype female (OSUC 231798). 55 Dorsal habitus 56 Lateral habitus 58 Head, ventral view, paratype female (OSUC 238205) 57 Head, anterior view 59 Metasomal sterna 5–6, ventral view. Morphbank²⁸

Figures 60–61.

Bracalba tricorata sp. n.,holotype female (OSUC 238541). 60 Dorsal habitus 61 Ventral habitus. Morphbank²⁹

Figures 62–65.

Bracalba tridentata sp. n.,paratype female (OSUC 238116). 62 Dorsal habitus 64 Head, ventral view, metasomal sterna 5–6, ventral view 65 Metasomal sterna 5–6, ventral view, holotype female (OSUC 238113) 63 Lateral habitus. Morphbank³⁰