Cephalcia arvensis Panzer, 1802

Liston, Andrew, Mutanen, Marko, Heidemaa, Mikk, Blank, Stephan M., Kiljunen, Niina, Taeger, Andreas, Viitasaari, Matti, Vikberg, Veli, Wutke, Saskia & Prous, Marko, 2022, Taxonomy and nomenclature of some Fennoscandian Sawflies, with descriptions of two new species (Hymenoptera, Symphyta), Deutsche Entomologische Zeitschrift 69 (2), pp. 151-218 : 151

Cephalcia arvensis Panzer, 1802

Fig. 6

Cephalcia arvensis Panzer, 1802: vol. 86 pl. 9. ♀. Syntypes. Type locality: Germany [according to title of work]. Blank et al. (2009); Nomen protectum with respect to Psen lucorum Schrank, 1802, nomen oblitum.

Cephalcia abietis var. intermedia Hellén, 1948: 40-41. ♀. Syntypes. Type locality: Russia, Karelia, Paanajärvi.

Cephalcia intermedia : Vikberg (1982); raised to species rank. Van Achterberg and van Aartsen (1986); synonymy with C. lariciphila (Wachtl, 1898). syn. nov.

Notes.

Cephalcia intermedia has in recent years mostly been understood as a distinct species close to C. arvensis (e.g. Viitasaari 2002b, Taeger et al. 2006), but with more extensively dark-patterned adults, occurring in northern Europe and the central European mountains. Because of its dark coloration, specimens of C. intermedia can also be mixed up with C. lariciphila (Wachtl, 1898), but the host plant of C. intermedia is Picea , as in C. arvensis , not Larix as in C. lariciphila . The status of C. intermedia and the supposed differences to C. arvensis were discussed by Vikberg (1982), Shinohara (1985), Midtgaard (1987) and Viitasaari (2002b). The only differences between C. arvensis and C. intermedia are in coloration: mainly of the abdomen, and less so of the antennae and legs. Shinohara (1985) pointed out that an unbroken range of color variability occurs between pale C. arvensis and the dark specimens identified as C. intermedia. This is in accordance with our observations, as the amount of dark color on the male abdomen varies considerably even in a single locality (Fig. 6 ). Small differences in colouration of larvae are possibly not constant, as the larvae of C. intermedia used for comparison were offspring of a single female. At present, there seems to be no convincing evidence for treating C. intermedia as a species distinct from C. arvensis , and we therefore synonymize them.

Figures

Figure 6. Cephalcia arvensis Panzer, 1802. Variability in colour pattern, dorsal habitus. A-D. Males (ZMUO. 032092, ZMUO. 033004, ZMUO. 030747, GP. 108460). E, F. Females (ZMUO. 040720, GP. 108471).