Gynoplistia fouldensensis, Nel & Kaulfuss, 2024

Nel, Andre & Kaulfuss, Uwe, 2024, A crane fly of the genus Gynoplistia Macquart (Diptera, Limoniidae) from the early Miocene of New Zealand, ZooKeys 1192, pp. 103-110 : 103

Gynoplistia fouldensensis sp. nov.

Fig. 2

Type material.

Holotype: New Zealand • sex unknown; an isolated wing; near Middlemarch, Otago; Foulden Maar Fossil-Lagerstätte; 45.5269°S, 170.2191°E; Geology Museum, Department of Geology, University of Otago (OU); OU46615.

Locality and horizon.

Foulden Maar diatomite, near Middlemarch, Otago, New Zealand; earliest Miocene, Aquitanian.

Diagnosis.

The wing venation of the new species strongly resembles that of the fossil G. (?) mitchelli in the shape of the radial and median veins. Still, G. fouldensensis sp. nov. but can be differentiated by the shape of discal cell and crossvein between M3 and M4 being more distal than basal part of M3.

Description.

Wing 8.8 mm long, 3.2 mm wide, with brown tinge, a series of white spots in anterior part and five series of transverse darker spots, veins black; Sc long, ending into C, extending far distal beyond fork of Rs, Sc-r just before tip of Sc; part of R5 basal to r-m elongate and oblique, R5 straight, reaching wing apex, 1.5 as long as Rs, R2+3+4 0.9 mm long; R2 beyond fork of R3 and R4; R3 3.0 mm long, slightly undulate; R4 3.4 mm long, straight; no supernumerary crossveins in cells r3, r4, and r5; r-m and m-cu not aligned, r-m situated a short distance past base of discal medial cell, m-cu situated midway between base and apex of discal medial cell; fork of vein M3+4 in apical section of discal medial cell; discal medial cell 1.4 mm long, 0.7 mm wide, closed; cell m1 present, c. 1.2 mm long; vein CuA straight; anal vein straight.

Etymology.

Named after the type locality Foulden Maar (Otago, New Zealand).

Discussion.

This wing corresponds to that of a Limoniidae because of the following characters (after de Jong 2017): well-developed CuP and anal vein; anal vein nearly straight; apex of vein Sc well developed; apices of R1 and R3 well separated; fork of vein M3+4 in apical section of discal medial cell; crossvein m-cu far removed from fork of M3+4; vein CuA straight. It is quite delicate to attribute an isolated fossil wing of Limoniidae to a genus because many genera are separated on the basis of body characters.

The combination of characters "cell m1 present, part of R5 basal to r-m elongate and oblique, and forked R2+3+4" is encountered in some species of the genera Gynoplistia , Pseudolimnophila Alexander, 1919, Hexatoma Latreille, 1809 (sensu lato), and Pilaria Sintenis, 1889. The Australasian species of Epiphragma Osten Sacken, 1860 also have a cell m1 and a forked R2+3+4, but their part of R5 basad r-m is very short, unlike in the new fossil.

Hexatoma (sensu lato) forms a morphology-based phylogenetic clade with Pseudolimnophila , Pilaria , and Ulomorpha ( Ribeiro 2008).

Pseudolimnophila and Ulomorpha are unknown in the Australasian/Oceanian region. Pilaria is represented by P. brooksi Alexander, 1953 in this region. This species has no cell m1 ( Alexander 1953).

Hexatoma is currently divided into six subgenera ( Podenas et al. 2022). The new fossil would fall in the subgenus Hexatoma Eriocera Macquart, 1838 because of the following characters: radial sector with three branches, medial cell distal, supernumerary crossveins missing in cells r3, r4, and r5, vein Sc reaching wing margin beyond Rs branching point, R2 beyond fork of R3 and R4 ( Podenas et al. 2022).

Following Oosterbroek (2024), Hexatoma is represented in the Australasian region only by five species of the subgenus Hexatoma Eriocera , which are Hexatoma (Eriocera) aperta (Alexander, 1920), H. (E.) atra (Doleschall, 1859), H. (E.) australiensis (Alexander, 1920), H. (E.) metallica (Schiner, 1868), and H. (E.) setifera (Alexander, 1931). The new fossil differs from all these species in the presence of cell m1. Also, H. (Eriocera) metallica differs from the new fossil in the uniformly infuscate wing and aligned r-m and m-cu ( Billingham and Theischinger 2022). Hexatoma (E.) australiensis also has wings with a "pale brown suffusion", and R2+3+4 "equal to or a little shorter than R3 alone" versus much shorter in the new fossil ( Alexander 1920: 104). Hexatoma (E.) aperta has "brownish gray" wings and H. (E.) setifera a blackish tinge, and both have an opened discal medial cell ( Alexander 1920: 105, 1931: 166). Hexatoma (E.) atra has R3 only slightly longer than R2+3+4, and m-cu is situated close to base of the discal medial cell ( Edwards 1921). Thus, the new fossil is not similar to any of these species.

Unlike the genera previously mentioned, Gynoplistia is very diverse in New Zealand, with 108 species listed by Oosterbroek (2024). Some representatives of this genus have patterns of wing coloration with colored bands and spots, very close to that of G. fouldensensis sp. nov. Theischinger (1993) proposed a revision of the Australian species of Gynoplistia . Affinities with the subgenus Gynoplistia Cerozodia Westwood, 1835 are excluded because of the vein Sc ending into C in the new fossil. The wing venation would rather fit with that of a species of the subgenera Xenolimnophila Alexander, 1922 or Gynoplistia for the narrow elongate cell r3, the oblique basal part of R5, the presence of cell m1, the vein m-cu not aligned with r-m, and the wing coloration with spots and bands ( Theischinger 1993: figs 9b, 11b). The New Zealand species of Gynoplistia also have wing coloration with spots and bands, but many have a basal part of R5 clearly less oblique than in the new fossil (e.g., Edwards 1923: pl. 30; Alexander 1939: pl. 28, fig. 1).

It is noteworthy that the wing venation of the fossil G. (?) mitchelli strongly resembles that of G. fouldensensis sp. nov., especially in the shape of the radial and median veins, but with an important difference in the shape of the discal cell, that is, the crossvein between M3 and M4 is more distal than basal part of M3 in the new fossil versus the contrary in G. (?) mitchelli ( Jarzembowski 1991: fig. 14). Indeed, the discal cell of G. (?) mitchelli resembles that of the H. (Eriocera) spp.

Figures

Figure 2. Gynoplistia fouldensensis sp. nov., holotype, OU 46615 A wing photograph B interpretative drawing of wing. Scale bar: 2 mm.