Culiseta (Neotheobaldia) frenchii (Theobald)

Harbach, Ralph E. & Wilkerson, Richard C., 2023, The insupportable validity of mosquito subspecies (Diptera: Culicidae) and their exclusion from culicid classification, Zootaxa 5303 (1), pp. 1-184 : 110

Culiseta (Neotheobaldia) frenchii (Theobald)

subspecies atritarsalis ( Dobrotworsky, 1954) —original combination: Theobaldia frenchi [sic] atritarsalis . Distribution: Australia (Victoria) ( Lee et al. 1988a).

subspecies frenchii ( Theobald, 1901c) —original combination: Culex frenchii . Distribution: Australia (South Gippsland, Victoria) ( Lee et al. 1988a).

It is surprising that Cs. frenchii has received comparatively little taxonomic attention. According to Dobrotworsky (1965) and Lee et al. (1988a), this species is only known with certainty from Victoria State of Australia —the Eastern Highlands (Great Dividing Range or Great Divide) and Gippsland (a region in the southeast), with the northwestern limit of its distribution being roughly defined by the isohyet of 100 cm of annual rainfall. Ironically, subspecies atritarsalis is only known from the highlands of South Gippsland ( Lee et al. 1988a), a region of rolling hills extending from Latrobe Valley in the north to the southernmost point of Victoria State. Larvae of the type form are found in the tunnels of terrestrial crayfish. In the absence of specific information, larvae of subspecies atritarsalis presumably occupy the same habitat ( Lee et al. 1988a).

When Dobrotworsky (1954) described subspecies atritarsalis , he stated that the male genitalia, pupa, larva and eggs are identical with those of the type form. This was reiterated by Dobrotworsky (1965), and Maslov (1967, 1989) also noted that “The distribution and ecology of these two subspecies are identical.” In his original description of frenchii , based on adult females, Theobald (1901c) provided illustrations of the head and wing. Edwards (1926a) described the male, but did so without illustrations. The male genitalia were later illustrated by Dobrotworsky (1954, 1965) and Maslov (1967, 1989), and the head and terminal abdominal segments of the larva were illustrated by Dobrotworsky (1965). The descriptions associated with the illustrations indicate the male genitalia and larvae were not studied in detail and were only superficially examined. None of the life stages of subspecies atritarsalis have been illustrated, and the immature stages have not been fully described for either subspecies.

Dobrotworsky (1954) briefly described the adults of subspecies atritarsalis as follows: “This subspecies is clearly distinguished from the type by its general darker colour; the thorax is brown, the proboscis, the palps [maxillary palpi] and the legs are clothed with almost black scales; the legs also are dark apically [in the type form “the last three segments of the tarsi are pale”]. The male palpi are even more hairy than those of the type, and the shaft apically has about thirty long hairs.” Maslov (1967, 1989) more succinctly stated that the “two subspecies differ in the following way: in the former [type form], the first 3 distal tarsal segments of all legs are completely light while, in the later [ atritarsalis ], the tarsi are entirely dark.” In the absence of detailed comparative anatomical data for all life stages of the two nominal forms, the entirely dark-scaled tarsi of atritarsalis , as opposed to the pale-scaled distal three tarsomeres of the type form, is sufficiently diagnostic to warrant recognition of the two forms as distinct, separate, seemingly sympatric species. Consequently, atritarsalis is hereby formally elevated to the rank of species: Culiseta (Neotheobaldia) atritarsalis ( Dobrotworsky, 1954) . Culiseta atritarsalis is currently listed as a species in the Encyclopedia of Life.