Calophytus, Irwin & Winterton & Metz, 2020

Irwin, Michael E., Winterton, Shaun L. & Metz, Mark A., 2020, New stiletto flies from New Caledonia (Therevidae, Agapophytinae), ZooKeys 984, pp. 83-132 : 83

Calophytus gen. nov.

Type species.

Calophytus chazeaui sp. nov., here designated.

Diagnosis.

Antennae elongate, longer than head, narrow cylindrical; frons wider than ocellar tubercle at narrowest point with only slight sexual dimorphism; dorsocentral macrosetae absent; velutum patches absent on femora; single posteroventral macroseta present midway along hind femur; wing with hyaline areas often free of microtrichia; distinct stripe of dark microtrichia bisecting cell br along wing fold; male genitalia with gonocoxites without velutum patch and medial atrium (gonocoxites proximal medially).

Description.

Antenna longer than head; flagellum cylindrical, slightly tapered distally, shorter than combined scape and pedicel length, rarely longer (in C. webbi sp. nov.); scape cylindrical, usually elongate; head shape in profile with length and height subequal; frons glossy, slightly protruding anterior to eye around base of antennae; frons wider than ocellar tubercle at narrowest point, only slight sexual dimorphism in frons width with space between eyes slightly narrower in male; parafacial without setae, postocular macrosetae in both sexes arranged in a single row dorsally, rarely scattered dorsomedially on occiput (in C. grandiosus sp. nov.); prosternum without setae; fore and hind femoral velutum patches absent; femoral macrosetae absent except for single posteroventral macroseta present midway along hind femur; posterior surface of mid coxa without setae; hind femur and tibia relatively longer than that of fore and mid legs; post-spiracular setae absent; scutal chaetotaxy (pairs): notopleural (np), 1-2; supra alar (sa), 1; post alar (pa), 1; dorsocentral (dc), 0; scutellar (sc), 1; wing cell m3 open to margin; wing vein R2+3 smoothly curved or straight to wing margin, wing with markings faint to strongly banded, hyaline areas often free of microtrichia; distinct stripe of dark microtrichia bisecting cell br along wing fold; abdominal tergite II with all setae uniform and regular in length. Male genitalia with dorsal apodeme of aedeagus ‘T’ -shaped, distiphallus narrow, straight, ventral apodeme forked; gonocoxite with velutum patch absent, posteromedial margins proximal to each other; inner gonocoxal process (igp) present and articulated; ventral lobe small, rounded apically. Female genitalia with tergite VIII elongate, quadrangular, anteromedial process narrow; tergite VII lacking anteromedial process; acanthophorite setae as two sets (A1 & A2), A1 enlarged and rounded apically, A2 series prominent; sternite VIII emarginate posteromedially, flattened; spermathecal sac present, not lobed; three sac-like spermathecae present, joined to spermathecal sac duct near junction with bursa copulatrix.

Etymology.

Derived from the Greek kallos, beauty; and phyton, plant, and relating to the charismatic appearance of the flies and the natural areas where they are collected in New Caledonia. The name also associates this genus with New Caledonia via the Proto-Celtic root of kal, hard, pertaining to the Roman name for the original provenance of Caledones in Britannia. Gender is masculine.

Comments.

All species of Calophytus gen. nov. are medium to large stiletto flies, with heads mostly glossy with striking patches of silver pubescence on the parafacial and pleuron, banded wings and antennae longer than the head. Distinctive to members of Calophytus gen. nov. is the presence of a single posteroventral macroseta midway along the hind femur and a stripe of microtrichia along the wing fold bisecting an otherwise glabrous wing cell br. These two characteristics are also found in the genus Squamopygia from Australia and Papua New Guinea and appear unique to these two genera amongst all Therevidae ; they are notably absent in Jeanchazeauia gen. nov. While Winterton et al. (2016) recovered a clear sister-group relationship between Calophytus gen. nov. and Jeanchazeauia gen. nov. (included in their study as undescribed genus ‘NC’) (Fig. 4 ), they did not include the rarely collected Squamopygia . The two aforementioned characters found only in Squamopygia and Calophytus gen. nov. also support a likely sister-group relationship between these two genera. Squamopygia is a monotypic genus with a single species from Northern Australia; two undescribed species are known from southern Australia and Papua New Guinea. Calophytus gen. nov. can be separated from Squamopygia by the absence of subapical anteroventral macrosetae on the hind femur (present in Squamopygia ), absence of dorsocentral macrosetae (present in Squamopygia ) and by the width of the male frons. The sexual dimorphism in male frons width is more pronounced in Squamopygia with the eyes being contiguous. In Calophytus gen. nov. (and Jeanchazeauia gen. nov.) the male frons is only slightly narrower than that of the female, with the frons wider than the ocellar tubercle in both sexes. Squamopygia also has banded wings similar to Calophytus gen. nov., but the hyaline areas of the wing membrane retain extensive pale microtrichia. The male and female genitalia of Squamopygia and Calophytus are very similar. Calophytus grandiosus sp. nov. is rather distinct from all other Calophytus species, differing in the arrangement of postocular macrosetae, wing banding pattern and body size, supporting its position as sister to the rest of the genus (Fig. 4 ). Calophytus species have been collected in all of the main habitat types throughout New Caledonia, including rainforest, maquis scrub and dry sclerophyll forest (Figs 22 , 31 , 32 ).

Included species.

Calophytus chazeaui sp. nov., C. grandiosus sp. nov., C. matilei sp. nov., C. monteithi sp. nov., C. schlingeri sp. nov., C. webbi sp. nov.

Figures

Figure 4. Phylogenetic placement of Calophytus gen. nov. and Jeanchazeauia gen. nov. in Agapophytinae based on supermatrix analysis of DNA sequence data. Figure modified after Winterton et al. (2016: fig. 3).

Figure 22. Distribution of Calophytus spp. collecting records throughout New Caledonia. Provinces are labelled and ecoregions delineated by colour.

Figure 31. Natural habitats of New Caledonian agapophytine stiletto flies A Riviere Bleue Reserve, sclerophyll forest and maquis scrub, habitat of C. chazeaui sp. nov., C. grandiosus sp. nov., C. schlingeri sp. nov., and J. nubilosus sp. nov. B Pindai Peninsula, tropical dry forest, habitat of C. webbi sp. nov. C Mount Dzumac, rainforest, habitat of J. nubilosus sp. nov. D Mount Dore, rainforest and dry sclerophyll forest E Mount Dore, Malaise trap in flyway (photographs by Michael E. Irwin).

Figure 32. Natural habitats of New Caledonian agapophytine stiletto flies A Mount Aoupinie, rainforest, habitat of C. monteithi sp. nov. B Mount Ningua, rainforest, habitat of J. nubilosus sp. nov. C Mount Mandjelia, habitat of C. grandiosus sp. nov. (photographs by Michael E. Irwin).