Oelandyla, Jaschhof & Jaschhof, 2020

Jaschhof, Mathias & Jaschhof, Catrin, 2020, The Porricondylini (Diptera: Cecidomyiidae: Porricondylinae) of Sweden revisited: descriptions of nineteen new species of ten genera, including a new genus, Zootaxa 4728 (2), pp. 151-182 : 163

Oelandyla gen. nov.

Type species, Oelandyla rostrata sp. nov., monotypic.

This new genus is introduced here to receive a new species of Porricondylini , whose unique combination of male characters (females and preimaginal stages are unknown) does not match the definition of any genus described in the past.

Diagnosis. Oelandyla conforms to most other porricondyline genera in having 14 male flagellomeres and no basitarsal spines ( Fig. 19 ), the reasons to place it in generic group Aa. Male morphology is partially atrophied, a fact reflected in the small body, short eye bridge, short palpus, and narrow wing ( Fig. 22 ). In this respect Oelandyla resembles other genera in group Aa, particularly Bryocrypta Kieffer and Neocolpodia . What makes Oelandyla unique among Porricondylini , both within and beyond group Aa, is the structure of the male genitalia ( Fig. 21 ). Four genitalic characters in combination are diagnostic: gonocoxal processes are absent; the gonostylus bears a medial, tooth-bearing process (↓ 1); the aedeagal apodeme is a simple, sclerotized rod; and the parameres, which are present as almost straight, sclerotized rods with flattened, rounded apices (↓ 2), are largely separate from each other (i.e. only basally connected through a weakly sclerotized bridge).

Etymology. The name Oelandyla combines Oelandia, the Latin name for Öland, with the suffix -yla. Öland is the Baltic island on Sweden’s southeast coast where the type species of this new genus was discovered, while –yla comes from Porricondyla , the type genus of the tribe Porricondylini .

Phylogeny. While we have no doubt that Oelandyla is a discrete genus of the tribe Porricondylini , its relationships to other genera remain obscure for the time being. This, we think, is due to the generally poor knowledge of Porricondylini diversity in the Palearctic region, rather than our failure to determine synapomorphies. Oelandyla might well belong to a poorly known lineage of Porricondylini whose center of recent distribution lies outside Europe.

Figures

FIGURES 19–24. Male morphology of Oelandyla rostrata (19–22) and Parepidosis kaltisbackensis (23–24), holotypes. 19: Basitarsus of foreleg, lateral. 20: Fourth flagellomere, lateral. 21: Genitalia, ventral. 22: Wing, dorsal. 23: Genitalia, ventral. 24: Fourth flagellomere, lateral. Scales for 19–21 and 23–24, 0.05 mm; for 22, 0.50 mm. Arrows refer to characters described in the diagnoses.