Siciliaria calcarae (Philippi, 1844) s. l.

De Mattia, Willy, Reier, Susanne & Haring, Elisabeth, 2021, Morphological investigation of genital organs and first insights into the phylogeny of the genus Siciliaria Vest, 1867 as a basis for a taxonomic revision (Mollusca, Gastropoda, Clausiliidae), ZooKeys 1077, pp. 1-175 : 1

Siciliaria calcarae (Philippi, 1844) s. l.

Remarks.

In the COI tree two subclades of Siciliaria calcarae s. l. appear together with S. leucophryna in an unresolved trichotomy. The subspecies of Siciliaria calcarae are distributed within two haplogroups, one (haplogroup 1) comprising the nominate subspecies as well as S. c. belliemii , S. c. borgettensis ssp. nov., S. c. orlandoi , S. c. parajatinensis ssp. nov. and the other one (haplogroup 2) consisting of S. c. cruenta ssp. nov. and S. c. jatinensis ssp. nov. Unfortunately, S. parajatinensis could not be included into the ITS2 analysis. Yet, given the low distances among all representatives of S. calcarae in the ITS2 tree (and the resulting bad resolution), this data set does not tell us much concerning these relationships. Thus, presently the close relationship between S. c. orlandoi and S. c. parajatinensis hast to rely on mt data only. Concerning the anatomy of the genital organs, shell morphology, distribution, ecology and haplogroup of Siciliaria calcarae , two general types can be distinguished for each category.

Genital organs.

Two main anatomical types of male (penial) internal sculpturing are found. The first type presents clear longitudinal pleats that run from the origin of penial pseudopapilla down to (or almost to) the atrium. These longitudinal pleats can be either (almost) completely smooth (Monte Belliemi) or more or less markedly fringed (Calatubo, Romitello, Ficuzza, Jato city park, Monte Kumeta, and Castelluzzo). The second type presents transverse and strong smooth pleats (Bonifato, Gibilmesi, and Visicari).

Sculpturing of the surface of the teleoconch.

The first type corresponds to S. calcarae calcarae (Philippi, 1844) morphotype, which is more or less striated (Bonifato, Ficuzza, Romitello, Visicari, Gibilmesi, and Castelluzzo), whereas the second type presents a markedly ribbed shell (Calatubo, Jato city park, Monte Kumeta, and Monte Belliemi).

Distribution.

Throughout the whole S. calcarae distribution, the nominate subspecies S. calcarae calcarae has the widest distribution, whereas all the remaining subspecies have an isolated, punctiform distribution. The populations from Alcamo, Visicari and Castelluzzo belong to the widely distributed nominate subspecies (1)m whereas the remaining populations (Ficuzza, Calatubo, Monte Kumeta, Jato city park, Romitello, Gibilmesi and Monte Belliemi) belong to limited, punctiform populations (2).

Ecology.

The populations belonging to this subclade were collected in two main ecological niches. Most of them (type 1) were found on limestone rocks and cliffs (Jato city park, Bonifato, Calatubo, Gibilmesi, Monte Kumeta, Romitello, Monte Belliemi and Visicari), whereas the other populations (type 2), from Ficuzza and Castelluzzo, were exclusively found on tree trunks.

Haplotypes.

Concerning the haplogroups of the Siciliaria calcarae clade, eight populations fall into subclade 1 (Bonifato, Calatubo, Romitello, Monte Belliemi, Visicari and Catselluzzo, Monte Kumeta, Ficuzza), whereas two populations (Gibilmesi, and Jato city park) fall in to the subclade 2. Siciliaria calcarae orlandoi Liberto et al., 2016 was recently described from a few scattered localities restricted to Bosco Ficuzza (Corleone, Sicily) ( Liberto et al. 2016: 371). The arrangement of the internal penial sculpturing of the holotype seems not matching with what was found by our dissection, where, instead of "two long weak longitudinal furrows" ( Liberto et al. 2016: 372) a set of transverse, interrupted fleshy smooth pleats were found instead. Yet, the authors provided besides pictures and description of the external morphology of the genital organs, only very few details on the internal morphology of the genital organs, namely: "internal walls of penis show two long weak longitudinal furrows; conic penial papilla, with slightly pointed apex and a restriction to the base". The brief description and the quality of the images ( Liberto et al. 2016: 375) do not allow accurate comparison of the internal features with those found in the present analysis. Moreover, the pseudopapilla was erroneously considered as a true penial papilla.

The position of S. calcarae orlandoi in the COI tree within haplogroup 1 is close to sequences of a population of Siciliaria from the western slopes of Monte Kumeta. Despite the close phylogentic relationship of this population with S. calcarae orlandoi , the differences in the arrangement of the internal male genital organs (a set of transverse, interrupted fleshy smooth pleats and epiphallus with two main fringed chords vs. smooth longitudinal pleats and smooth proximal epiphallus) as well as the remarkable differences concerning shell morphology (see also Liberto et al. 2016: 372 for a comparative discussion with conspecific taxa) we propose the population from Monte Kumeta as S. calcarae parajatinensis ssp. nov.

Two additional new subspecies of Siciliaria calcarae will be described in the following sections: S. calcarae borgettensis ssp. nov. and S. calcarae cruenta ssp. nov. Both taxa, despite showing close phylogenetic relationships with the other Siciliaria calcarae taxa, present distinctive shell and genital characters strong enough to propose their description as new subspecies.