Cryptocephalus zambanellus Marseul, 1875

Sassi, Davide, 2014, Taxonomic remarks, phylogeny and evolutionary notes on the leaf beetle species belonging to the Cryptocephalus sericeus complex (Coleoptera: Chrysomelidae: Cryptocephalinae), Zootaxa 3857 (3), pp. 333-378 : 339-340

Cryptocephalus zambanellus Marseul, 1875

Cryptocephalus zambanellus Marseul, 1875: 130 . Type locality: Monzambano, Italy. Type: not examined.

The taxonomy of Cryptocephalus sericeus seems rather confusing in determining the status of Cryptocephalus zambanellus Marseul. This latter taxon has been considered by some authors as a subspecies of C. sericeus ( Warchalowski, 2003, Gómez-Zurita et al., 2011) and by others it was treated as a distinct species ( Lopatin et al., 2010; Petitpierre, 2000). It should also be noted that Burlini, who for decades represented the most authoritative entomologist in the study of European Cryptocephalus , had always considered C. zambanellus a subspecies of C. sericeus ( Burlini, 1956) . Because of these taxonomic uncertainties I re-examined this issue in detail. On the basis of specimens collected in Italy (Monzambano, near Mantua), Cryptocephalus zambanellus was described by Marseul (1875) as a species and not as a "variety", as erroneously reported by de Monte (1948). Marseul separated it from C. sericeus because of the absence of the bituberculate small ridge on the anterior margin of the anal depression that characterizes male specimens of this taxon (fig. 10). Since then, Weise (1881) described and named specimens of C. sericeus collected near Trieste, in Croatia and Dalmatia as C. sericeus var. intrusus , distinguished from the nominal form on the basis of the same morphological characters, i. e. the lack of the bituberculate ridge. At that time the author did not know the taxon described by Marseul (1875) and later on he hastened to synonymize intrusus with C. zambanellus in "additions and corrections" in a footnote of his following work ( Weise, 1893). In the following years C. zambanellus was deemed alternately as a distinct species ( Breit, 1918; Winkler, 1930; Porta, 1934; Zangheri, 1969) or as a "variety" or subspecies of C. sericeus ( Weise, 1906; Clavareau, 1913; Ulrich, 1923; de Monte, 1948; Müller, 1952; Burlini, 1956).

Besides, de Monte (1948) resurrected the name intrusus from synonymy with subsp. zambanellus , proposing it as a distinct subspecies of C. sericeus for specimens collected from Venezia Giulia only, highlighting peculiarities in the structure of the first sclerite of endophallus and in the shape of the male anal pit. He acknowledged, however, that from some localities (Tolmin, Postojna) there were specimens with ambiguous features. Besides, de Monte reported a rather strong variability in specimens from the Dalmatian coast and from the Velebit. However, he still assigned these latter populations, with some doubt, to C. sericeus ssp. zambanellus .

In more recent times Rozner & Rozner (2008) awarded a specimen collected in the Republic of Macedonia (Kratovo, Zguri-pass,) to the taxon C. zambanellus .

After the analysis of several tens of specimens from Venezia Giulia, Slovenia, Croatia and Dalmatian Islands, I feel the situation can be evaluated as follows. I confirm the existence of intermediate specimens, i.e. “ intrusus ” sensu de Monte (1948), between C. zambanellus and C. sericeus in populations spread in Italian territories between the valley of Tagliamento river and the state border, on the whole Istrian peninsula up to Rijeka, and on Slovenian territories up to the vicinity of Postojna. It must therefore be noted that the area covered by these intermediate populations joins to the north and east with that of C. sericeus , and abruptly bisects to the west the range of C. zambanellus , as the populations of the Dalmatian coast south of Istria should be attributed to the latter taxon (pers. obs., but see also de Monte, 1948; Müller, 1953). On the other hand it is remarkable that C. zambanellus and C. s ericeus never show transitional forms along the northern and western border area. In Italy, C. sericeus is reported only from a single locality (Tarvisio) very close to the Austrian border ( Burlini, 1956). In France, C. sericeus can be found at a short distance from the Italian border, being present in the Queyras and Savoye (Lanslevillard) while maintaining the typical habitus. All the Italian specimens I examined, even if collected very close to the French border (i.e. Vinadio, Limonetta, Sampeyre) belong with no doubts to C. zambanellus . Conversely, transalpine and Central European specimens never reveal morphological characters that match the pattern of the latter form. Considering the broad extent of C. sericeus ’ range, ambiguous morphological intermediates (“ intrusus ”) occurring in the northeastern part of zambanellus ' range may be explained with the existence of a moderate area of introgression between two otherwise distinct species that reveal a global well-established genetic isolation. For this reason, I reiterate the opportunity to compose this taxonomic framework:

Cryptocephalus zambanellus Marseul, 1875: 130 stat. nov.

Cryptocephalus intrusus Weise, 1881: 183 n. syn.

Cryptocephalus sericeus intrusus Weise ( De Monte, 1948: 471) .