Parydra (Chaetoapnaea) undulata Becker, 1896

Stuke, Jens-Hermann, 2025, Taxonomic and faunistic comments on European Parydra Stenhammar, 1844 (Diptera: Ephydridae) with new species from Finland and Jordan, Zootaxa 5686 (1), pp. 49-105 : 98

Parydra (Chaetoapnaea) undulata Becker, 1896

( Fig. 21 )

Parydra undulata Becker 1896: 213 ; type-locality: „Gouvernment Minsk“, „Wannsee bei Berlin “; syntype ♂ ♀ [ZMB, Mathis & Zatwarnicki 1995].

Primary type material examined:

♂ syntype of P. undulata in coll. ZMB with these labels (1) “[illegible sign]”; (2) “ Polen 3664.”; (3) “Typus”; (4) “ Parydra / undulata / Beck. / M. Krivosheina det., 1985”

Material examined: Material: GERMANY: 1♂, 7.viii.2011, Saxony-Anhalt, Salziger See, Igelsumpf [51.470°N 11.6787°E] ; FRANCE: 1♀, 18.vii.2001, Landes, Vielle-St Girons, w Lac de Léon [43.895°N 1.334°W], leg. J.-P. Haenni.

Diagnosis: Due to the unique undulating wing venation and the wing colouration ( Fig. 21 ) this species cannot be confused with any other Parydra .

Taxonomy: Although the male terminalia could not be examined there is no doubt that P. undulata belongs to the subgenus Chaetoapnaea (new subgenus position). All characters of P. undulata conform to the description of Clausen & Cook (1971). With the exception of the wing venation, it is extremely similar to other species of Chaetoapnaea such as P. hecate . In fact, given its closeness to P. hecate and the fact that I have seen one specimen with intermediate wing characters, I cannot rule out that P. undulata may only be a form of P. hecate with misshapen wing venation.

Distribution in Europe: A rarely collected and local species. There are several records from coastal wetlands in southeast England (NBN Atlas 2024), one record from France reported here, records from three saline wetlands in eastern Germany ( Stuke & Bährmann 2013), one location at a Polish inland saline wetland ( Szadziewski 1983, Soszyński et al. 2000), and the historical type locations reported by Becker (1896) „Gouvernment Minsk“ and „Wannsee bei Berlin “. Additionally, Mathis & Zatwarnicki (1995) report P. undulata as occurring in Austria and Sweden without citing a source.

Biology: Hardly anything is known about this rare species. Recent records suggest that P. undulata is a halophilous species occurring coastal and inland saline habitats. In Germany it has recently been recorded from dense vegetation at the margin of salt lakes.

Figures

FIGURE 21. Habitus of Parydra undulata Becker.