Hexatoma

Podeniene, Virginija & Gelhaus, Jon K., 2015, Review of the last instar larvae and pupae of Hexatoma (Eriocera) and Hexatoma (Hexatoma) (Diptera, Limoniidae, Limnophilinae), Zootaxa 4021 (1), pp. 93-118 : 95

Key to the known last instar larvae of Hexatoma of Mongolia

1. Apex of ventral lobes of spiracular disc with cluster of similar length hairs, but lacking several much longer setae ( Fig. 26 ). Maxillary palpus as long as mandible ( Fig. 21 ). Last instar larvae large, more than 30 mm long.................................................................................. Hexatoma (Eriocera) sachalinensis (Alexander, 1924)

- Apex of ventral lobes of spiracular disc with cluster of similar length hairs, and several much longer setae ( Fig. 33 , 44 ). Maxillary palpus almost twice as long as mandible ( Fig. 1 ). Last instar larvae about 20 mm long.......................... 2

2. Marginal hairs on the tips of lobes dark brown, in other parts light brown. Each ventral lobe of the spiracular field covered with a wide “Y” shaped sclerite, the dorsal inner branch fused with its opposing sclerite ( Fig. 44 )........................................................................................ Hexatoma (Eriocera) ussuriensis Alexander, 1934

- All marginal hairs of spiracular lobes light brown. Each ventral lobe of the spiracular field covered with a wide “Y” shaped sclerite, completely separate from its opposing sclerite ( Fig. 33 , 57 ) .............................................. 3

3. “Y” shaped sclerite of each ventral spiracular lobe with widest part no wider than sclerite of lateral lobe............................................................................. Hexatoma (Eriocera) stackelbergi Alexander, 1933

- “Y” shaped sclerite of each ventral spiracular lobe with widest part over twice as wide as sclerite of lateral lobe.................................................................... Hexatoma (Hexatoma) nubeculosa (Burmeister, 1829)

Figures

FIGURES 21 – 28. Hexatoma (Eriocera) sachalinensis. 21. General view of head capsule of last instar larva, dorsal aspect. 22. Labrum, dorsal view. 23. Labrum and clypeus, dorsal view. 24. Right mandible, dorsal view. 25. Right antenna, dorsal view. 26. Spiracular field. 27. Penultimate segment and terminal segment, ventral aspect. 28. Penultimate segment and terminal segment, lateral aspect.

FIGURES 29 – 33. Hexatoma (Eriocera) stackelbergi. 29. Penultimate segment and terminal segment, ventral aspect. 30. Labrum and clypeus, dorsal view. 31. Right mandible, dorsal view. 32. Right antenna, dorsal view. 33. Spiracular field.

FIGURES 39 – 45 Hexatoma (Eriocera) ussuriensis. 39. Penultimate segment and terminal segment, ventral aspect. 40. Labrum, dorsal view. 41. Labrum and clypeus, dorsal view. 42. Right mandible, dorsal view. 43. Right antenna, dorsal view. 44. Spiracular field. 45. Penultimate segment and terminal segment of last instar larva, lateral aspect.

FIGURES 1 – 5. Hexatoma (Eriocera) californica. 1. General view of head capsule of last instar larva, dorsal aspect. 2. Labrum and clypeus, dorsal aspect. 3. Right mandible, dorsal view. 4. Right antenna, dorsal view. 5. Spiracular field.

FIGURES 54 – 57. Hexatoma (Hexatoma) nubeculosa. 54. Labrum and clypeus, dorsal view. 55. Right mandible, dorsal view. 56. Right antenna, dorsal view. 57. Spiracular field.