Charpentieria itala: subspecies, species, superspecies
Hartmut Nordsieck (VII.2020)
I. Introduction and history
In the revision of the Charpentieria species from the southern limestone Alps (NORDSIECK 1963: 174-190, as Delima) I tried to describe the intraspecific diversity of C. itala (G. VON MARTENS 1824) by a subdivision of the species of that region into several subspecies. These are (from W to E) C. i. albopustulata (CRISTOFORI & JAN 1832), C. i. latestriata (KÜSTER 1850), C. i. rubiginea (ROSSMÄSSLER 1836), and C. i. serravalensis (H. NORDSIECK 1963), besides, as transitional forms within C.i. albopustulata, but later on treated as subspecies, C. i. braunii (ROSSMÄSSLER 1836) and C. i. baldensis (CHARPENTIER 1852) [already described by STROBEL (1851: 25)]. A complex of forms from the same region which in shell morphology and ecological preferences are similar to the related species C. stenzii (ROSSMÄSSLER 1836), but in genital morphology largely correspondent with C. itala and in part connected with it by transitional forms, was included in the latter as so-called stenzioid subspecies (NORDSIECK 1963: 171-173, 181-187): C. i. clavata (ROSSMÄSSLER 1836), C. i. variscoi (PINI 1883), C. i. balsamoi (STROBEL 1850), C.i. lorinae (GREDLER 1869). Later on, because of its semispecies character, that complex has been separated as species C. clavata (NORDSIECK 1979: 259).
In the 1963 paper the subspecies of C. itala from the remaining distributional range (Monti Berici and Colli Euganei, Provence, Maritime and Ligurian Alps, northern and central Apennines) were not considered. The related species C. dyodon (STUDER 1820) from Piedmont was not treated either, because at this time its close relationship to C. itala was not known.
ZILCH (1972), in a type catalogue of the Delimini, has also listed the subspecies of C. itala outside the southern Alps: C. i. itala from Monti Berici and Colli Euganei, and C. i. nigra (ISSEL 1866) and C.i. punctata (MICHAUD 1831) from the remaining range.
Several Italian authors called in question the proposed subdivision of C. itala into subspecies, with the following arguments:
GIUSTI & MAZZINI (1971: 294): "Sulla scorta delle sue descrizioni [NORDSIECK 1963] abbiamo provato a determinare alcuni materiali dell' Italia settentrionale, tuttavia, senza riuscirci mai con sicurezza. Tanto variabili sono i caratteri conchiliologici ..."
BOATO et al. (1985: 312): C. itala cfr. punctata: "..., sia questa, che le numerose altre che normalmente si includono nella C. itala sono spesso variabili e poco definite".
MANGANELLI et al. (1995: 47): "Molte delle entità sottospecifiche convalidato da NORDSIECK (1963 ...) e da ZILCH (1972 ...) qui riportate appaiano di validità dubbia".
These statements, however, are only opinions, not substantiated by further investigations.
Therefore, for this chapter the shell characters, on which the subspecies division of C. itala was based, have been checked once more, and the revision of 1963 was supplemented by the inclusion of the forms from beyond the southern Alps and of C. dyodon from Piedmont. The stenzioid subspecies of C. itala = C. clavata and the transitional subspecies C. i. allatollae (KÄUFEL 1928) were not considered in this revision, because new results could not be expected. The examined shell material of C. itala has been augmented by a third (from 350 samples for the 1963 paper to 460 for this chapter), and 25 samples of C. dyodon have been included. The material is deposited in the collection of the Forschungsinstitut Senckenberg (SMF) and in my own collection (deposited mainly in the Staatliches Museum für Naturkunde Stuttgart).
It resulted that the most important characters, those of lunellar and clausilium plate, are not at all too variable and are therefore suited for the definition of subspecies. Obviously, these characters were not considered or not understood by the named authors (because the paper was written in German). In the following they are once more described and figured.
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