Psila, Meigen, 1803

Lauriaut, Christophe & Claude, Jocelyn, 2022, Note on Psila helvetica Shatalkin & Merz, 2010: a new rust fly (Diptera: Psilidae) for mainland France, with key to French species and male genitalia illustration, Zootaxa 5188 (3), pp. 297-300 : 299-300

Replacement for Psila identification key provided by Withers & Claude (2021)

English version

1 Mesonotum and subscutellum yellow. Postpedicel mainly yellow (sometimes with a blackened area at the base of the arista). Aedeagus shorter than the genitalia, not protruding below the sternites........................................... 2

- Mesonotum with black stripes and subscutellum black. Postpedicel mostly black. Aedeagus longer than the genitalia ( Fig. 5 ), and often protruding below the sternites ( Fig. 3 )............................. Psila helvetica Shatalkin & Merz, 2010

2 Postpedicel yellow-orange, blackened at the base of the arista. Genitalia as in Fig. 43 in Withers & Claude (2021)................................................................................... Psila fimetaria (Linnaeus, 1761)

- Postpedicel unicolourous (yellow-orange), without black spot at the base of the arista. Genitalia as in Fig. 44 in Withers & Claude (2021)................................................................. Psila merdaria Collin, 1944 .

French version

1 Mésonotum jaune et subscutellum jaune. Postpedicel principalement jaune (parfois avec une zone noircie à la base de l’arista). L’édeage est plus court que le genitalia, et ne dépasse pas sous les sternites........................................ 2

- Mésonotum avec des rayures noires et subscutellum noir. Postpedicel principalement noir. L’édeage est plus long que les genitalia ( Fig. 5 ), et souvent dépasse sous les sternites ( Fig. 3 ).................. Psila helvetica Shatalkin & Merz, 2010

2 Postpedicel jaune-orange, noirci à la base de l’arista. Genitalia comme dans la Fig. 43 dans Withers & Claude (2021)................................................................................ Psila fimetaria (Linnaeus, 1761)

- Postpedicel unicolore (jaune-orange), sans tache noire à la base de l’arista. Genitalia comme dans la Fig. 44 dans Withers & Claude (2021)................................................................. Psila merdaria Collin, 1944 .

Specimens caught in France confirm the late flight period (mid-August to mid-September) of Psila helvetica . The altitudes are also concordant (650 to 1200 m a.s.l.). Examination of the genitalia confirms that Psila helvetica differs from other European species of Psila . After Switzerland ( Shatalkin & Merz 2010) and Finland ( Kahanpää & Salmela 2014), France is the third country known for Psila helvetica . The list of Psilidae from France now stands at 38 species, including three Psila sp. However, knowledge of the French fauna remains modest, with other species to be described in the near future, in particular for the genus Chamaepsila Hendel, 1917 .

Figures

FIGURES 5–6. Genitalia of Psila helvetica Shatalkin & Merz, 2010. 5: in ventral view. Scale bar = 0.3 mm. 6: left epandrium in lateral view. Scale bars = 0.1 mm. (Drawings: Jocelyn Claude).

FIGURES 2–4. Habitus of Psila helvetica Shatalkin & Merz, 2010 in dorsal view with aedeagus indicated by arrow (2), ventral view (3) and head in front (4). (Photos: Christophe Lauriaut).