Cretosabethes primaevus Amaral & Borkent, 2025 (in Amaral et al., 2025).
Subfamily Culicinae, tribe Sabethini. Cretosabethes is currently monobasic. Genus abbreviation – Cr.
LARVA (adults, pupae and eggs unknown): Antenna borne posterolaterally near the occipital region; maxilla with a claw-like apical tooth; occipital foramen slightly stretched laterally; seta 1-C slender, weakly sclerotised; seta 13-T is borne on a plate with setae 9–12-T; seta 1-S multi-branched, 2a-S inserted about 0.3 from base of siphon; seta 4-X of each side with 2 strongly developed setae, setae of opposite sides widely separated, not borne on a common ventrocaudal plate. See Sabethini.
The larva of the type species shares morphological features with larvae of the extant genus Trichoprosopon, including seta 1-C single, simple and slender; seta 13-T inserted on a plate with setae 9–12-T; and absence of a comb. Seta 13-T is also borne on a plate with setae 9–12-T in species of the extant genera Kimia and Isostomyia.
It is highly likely that the immature stages of species of Cretosabethes developed in phytotelm habitats, which explains the preservation of the larva of Cr. primaevus in amber. The presence of adult females of biting midges of the nominotypical subgenus of Leptoconops as syninclusions, most extant species of which oviposit and forage on sandy beaches, suggests that Cr. primaevus inhabited a coastal environment. The sparse, club-shaped, serrate? elements of the lateral palatal brushes suggest that the larva fed by browsing whereas the apical tooth of the maxilla suggests that the larva may have been capable of capturing and devouring living organisms, a facultative predator. Amaral et al. (2025) inferred that Cr. primaevus “was both a browser and a facultative predator.”
The single known species of Cretosabethes is from Hukawng Valley, Kachin State, Myanmar. As explained by Amaral et al. (2025), “Kachin amber, part of the Burma Terrane, or West Burma Block” was part of Gondwana that probably separated from Australia during the Lower Cretaceous (or earlier) of the Mesozoic, before drifting northwards and becoming attached to the Greater Indian Plate.
Amaral et al., 2025 (new genus, diagnosis, description of type larva, phylogenetic aspects).
primaevus Amaral & Borkent, 2025 (in Amaral et al., 2025) (98.79 ± 0.62 Mya, Mesozoic, Upper Cretaceous, around the Albian–Cenomanian boundary).