Campoplex difformis (Gmelin, 1790)

Scaramozzino, Pier Luigi, Giovanni, Filippo Di, Loni, Augusto, Ricciardi, Renato & Lucchi, Andrea, 2018, Updated list of the insect parasitoids (Insecta, Hymenoptera) associated with Lobesiabotrana (Denis & Schiffermueller, 1775) (Lepidoptera, Tortricidae) in Italy. 2. Hymenoptera, Ichneumonidae, Anomaloninae and Campopleginae, ZooKeys 772, pp. 47-95 : 47

Campoplex difformis (Gmelin, 1790)

Campoplex difformis : Nuzzaci and Triggiani 1982: 49.

Italian distribution of reared parasitoids.

Apulia: Nuzzaci and Triggiani 1982 [on Daphne gnidium L.].

Distribution.

The species is present throughout Europe up to the Caucasus and Uzbekistan, the Canary Islands and Madeira, Tunisia and Greenland ( Yu et al. 2012; Zwakhals and van Achterberg 2017).

Host range.

Yu et al. (2012) list 64 host species belonging to 18 different families (15 of Lepidoptera and 3 of Hymenoptera ). This long list has to be verified, because in the past the specific interpretation of C. difformis was rather uncertain (see taxonomic notes under C. capitator and Horstmann 1985). The most represented family is that of Tortricidae , with 35 species (including L. botrana and E. ambiguella ). Tortricids could be actually the only hosts of C. difformis , because all known hosts of the “difformis” species-group belong to this family ( Horstmann 1985). Archips podana (Scopoli, 1763) was the only host ascertained for this species in the work of Horstmann (1985). In Evenhuis and Vlug (1983), a hypothetical Campoplex difformis , so identified by Horstmann, is reported attacking three other tortricid species, Pandemis cerasana ( Hübner, 1786), Adoxophyes orana (Fischer v. Röslerstamm, 1834) and Acleris rhombana (Denis & Schiffermüller, 1775).

Ecological role.

Campoplex difformis is a koinobiont larval endoparasitoid often reported as a parasitoid of E. ambiguella in France ( Voukassovitch 1924). Its larva kills the moth larva when it is ready to pupate, and weaves its own cocoon next to the host spoils ( Marchal 1912, Voukassovitch 1924). In Apulia (Southern Italy), this species occurred frequently, showing a parasitism rate of approx. 4% on EGVM larvae feeding on Daphne gnidium ( Nuzzaci and Triggiani 1982). The species has been reported on L. botrana in Austria, France, Germany, Russia, Spain and Bulgaria, as well as in Italy ( Thompson 1957, Zapryanov and Stoeva 1982, Zapryanov 1985).

Campoplex difformis is itself the victim of Dibrachys microgastri ( Bouché, 1834) ( Hymenoptera Pteromalidae ) ( Faure and Zolotarewsky 1925, Zapryanov and Stoeva 1982), Perilampus tristis Mayr, 1905 ( Hymenoptera Perilampidae ) ( Thompson 1958) and Cirrospilus sp. ( Hymenoptera Eulophidae ) ( Noyes 2017).

Taxonomic notes.

Campoplex difformis (Gmelin) was designated as the type species of the genus Campoplex Gravenhorst, 1829 by Westwood (1840). It also gives the name to a complicated group of very similar species, with morphological characteristics insufficient to allow a definitive identification ( Jenner et al. 2013). In the past this species was mainly attributed to the genera Limneria Holmgren, 1859 and Omorgus Förster, 1869 (= Omorga Thomson, 1887). Unfortunately, the interpretation of the species Ichneumon difformis Gmelin, until the studies of K. Horstmann (1969, 1985), has been uncertain. The type of Gmelin was destroyed. Then, following the first interpretation of the species given by Gravenhorst (1829), Horstmann fixed the lectotypus of Limneria mutabilis Holmgren, in Holmgren’s collection in Stockholm as a neotypus of C. difformis ( Horstmann 1969, 1985). Thus, C. mutabilis of Holmgren became a junior synonym of C. difformis , and C. difformis sensu Holmgren (and Thomson) became Campoplex deficiens Gravenhorst, 1829. Therefore, the interpretation of the species given by Gravenhorst (1829) [and hence by Horstmann (1985)] differed from that of other taxonomists (mainly Holmgren, Thomson and Schmiedeknecht), who considered C. difformis and C. mutabilis two distinct species. For this reason Aubert (1971, 1974 and 1981), another leading authority in the ichneumonid taxonomy, rejected the neotypus fixed by Horstmann and created another typus in the collection of Thomson in Lund, in order to keep C. mutabilis as a separate species from C. difformis . Consequently, C. deficiens Gravenhorst became synonym of C. difformis (see Table 7). In this work we follow the interpretation of Gravenhorst (1829), Horstmann (1969, 1985), and Yu and Horstmann (1997). Campoplex difformis has three synonyms: Campoplex lineolatus Ratzeburg, 1844, Limneria mutabilis Holmgren, 1860 and Nepiera algerica Habermehl, 1922, and a variety with dark hind legs (var. obscuripes Greese, 1927).