Cochlostoma (Clessiniella) tergestinum ( Westerlund, 1878 )

Zallot, Enrico, Mattia, Willy De, Fehér, Zoltán & Gittenberger, Edmund, 2021, Cochlostoma revised: the subgenus Clessiniella Zallot et al., 2015 (Caenogastropoda, Cochlostomatidae), European Journal of Taxonomy 762 (1), pp. 49-95 : 82-87

Cochlostoma (Clessiniella) tergestinum ( Westerlund, 1878)

Figs 1 , 3B , 5 , 14C , 15C , 16C , 28–30 , 34 (bottom), 35 (bottom), 36 (top)

Pomatias tergestinus Westerlund, 1878: 108–109 (“Triest”).

Pomatias tortivus Westerlund, 1885: 124 (“Fiume, San Daniel u. Karstgebirge”, which should be Rijeka in Croatia and Štanjel in Slovenia).

Pomatias tergestinus var. grahovana A.J. Wagner, 1897: 616 , pl. 9 fig. 89 (“Grahovo bei Fiume”, a locality ca 10 km north of Rijeka in Croatia).

Pomatias tergestinus var. tortiva – A.J. Wagner 1897: 616, pl. 9 fig. 88.

Cochlostoma tergestinum − Welter-Schultes 2012: 102.

Diagnosis

Shell very variable, lip curved backwards more or less abruptly at the columellar side. Strong ribs on the teleoconch, in most of the populations widely spaced and, on the upper whorls, whitish and contrasting with the corneous, dark brown to light yellow, shell background. Visceral oviduct with convoluted loops path; body spermiduct straight.

Type material

Syntypes ITALY • “Triest” [ Friuli Venezia Giulia, Trieste ]; Westerlund leg.; SMF160677/1 • same label data as for preceding; SMF 160676/7 ( Fig. 30 ) .

Other material

AUSTRIA • Dobratsch ; 46.59222° N, 13.6825° E; 2009; Mildner and Giovannelli leg.; EZ0799 • Kranzwand ; 46.588799° N, 13.75002° E; Jul. 2015; AL leg.; NHMW109000 .

CROATIA • Sveta Nedelja near Labin; 45.13741° N, 14.14488° E; 2000; De Mattia leg.; WdM6961 • Brest , Cicaria; 45.45444° N, 14.00625° E; Apr. 2008; De Mattia leg.; WdM6715 • Drivenik spring; 45.24147° N, 14.64828° E; Mar. 2009; De Mattia leg.; WdM6714 • from A6 to 501 down Bakar; 45.30543° N, 14.58579° E; Jul. 2009; De Mattia and Zallot leg.; EZ0938 • Jakačici ; 45.179494° N, 14.004384° E; 2009; De Mattia leg.; WdM6699 • Kremenje-Buje ; 45.43558° N, 13.68499° E; Jan. 2008; De Mattia leg.; WdM6400 • Kukurini ; 45.19369° N, 14.07216° E; Feb. 2009; De Mattia leg.; WdM6698 • Limski Kanal ; 45.12957° N, 13.74039° E; 2010; De Mattia leg.; WdM6693 • Limski Kanal ; 45.12957° N, 13.74039° E; Jun. 2010; De Mattia leg.; WdM6998 • Mala Ucka ; 45.27605° N, 14.19715° E; 2009; De Mattia leg.; WdM6768 • Meja , Bakarac; 45.3037° N, 14.58348° E; 2009; De Mattia leg.; WdM6951 • Momjan ; 45.442° N, 13.71384° E; 2009; De Mattia leg.; WdM6854 • Mt Učka , beech forest ; 45.30636° N, 14.20865° E; 2009; De Mattia leg.; WdM6794 • Mt Učka , top; 45.28967° N, 14.20341° E; 2009; De Mattia leg.; WdM6794 • Pazin ; 45.24134° N, 13.93099° E; Jun. 1986; Drimmer leg.; HNHM97227 • Permani ; 45.43742° N, 14.28905° E; 2009; De Mattia leg.; WdM6708 • Raša ; 45.0872° N, 14.08854° E; 2010; De Mattia leg.; WdM6968 • Rasko Polje ; 45.15638° N, 14.0538° E; 2010; De Mattia leg. • EZ0813 • Rasko Polje ; 45.15638° N, 14.0538° E; 1900; De Mattia leg.; EZ1027 • Zminj ; 45.13991° N, 13.88873° E; 2000; De Mattia leg.; WdM6700 .

ITALY • Val Rosandra ; 45.62° N, 13.87139° E; 2000; Zallot leg.; EZ0840 • Torri di Monrupino ; 45.71878° N, 13.80594° E; 1998; Zallot leg.; EZ0839 .

SLOVENIA • Abram-Nanos Mt ; 45.82055° N, 14.01433° E; 2008; De Mattia leg.; WdM6731 • Brestovica pri Komnu ; 45.80996° N, 13.65016° E; 2009; De Mattia leg.; WdM6948 • Čepno ; 45.67071° N, 14.09732° E; Jun. 2009; De Mattia leg.; WdM6866 • Črnotiče-Črni Kal ; 45.55276° N, 13.88633° E; Mar. 2009; De Mattia leg.; EZ1028 • Dolina Nanos-Abran-Podkraj ; 45.79813° N, 14.06699° E; Apr. 2009; De Mattia leg.; WdM6733 • Farjev Vrh ; 45.92429° N, 13.95442° E; 2009; De Mattia leg.; WdM6740 • Golac, Vela Vrata ; 45.51315° N, 14.02969° E; 2009; De Mattia leg.; WdM6762 • Gorjansko ; 45.78485° N, 13.70068° E; 2000; De Mattia leg.; WdM6950 • Hruščica ; 45.85832° N, 14.1117° E; 2000; De Mattia leg.; WdM2409 • Ilirska Bistrika ; 45.56944° N, 14.23917° E; 2009; Zallot leg.; EZ0821 • Kovk ; 45.94614° N, 13.95058° E; 2015 • De Mattia leg.; WdM6737 • Križna Jama ; 45.82003° N, 14.24579° E; Jun. 2009; Jochum leg.; HNHM97142 • Markovščina-Dimnice cave ; 45.58357° N, 14.03994° E; 2009; De Mattia leg.; WdM6765 • Mt Kobilica ; 46.06528° N, 13.80907° E; 2005; De Mattia leg.; WdM6849 • Mt Nanos, top, loc. Plesa ; 45.79813° N, 14.06699° E; Jun. 2005; De Mattia leg.; WdM0000 • Mt Snežnik 1161; 45.56816° N, 14.37049° E; Jun. 2010; De Mattia leg.; WdM7012 • Mt Snežnik 1390; 45.57179° N, 14.41044° E; Jun. 2010; De Mattia leg.; EZ0965 • Mt Snežnik 1447; 45.57877° N, 14.43839° E; Jun. 2010; De Mattia leg.; EZ0964 • Mt Snežnik 1450; 45.58195° N, 14.43129° E; Jun. 2010; De Mattia leg.; EZ0962 • Mt Snežnik car parking ; 45.58235° N, 14.43117° E; Jun. 2002; De Mattia leg.; WdM7006 • Mt Vremščica ; 45.69898° N, 14.03388° E; 2009; De Mattia leg.; WdM6758 • near Gorenje; 45.82976° N, 14.10755° E; 2009; Zallot leg.; EZ0817 • near Logatec; 45.88076° N, 14.27448° E; 2009; Zallot leg.; EZ0828 • Osp , 45.57071° N, 13.86168° E; 2010; De Mattia leg.; WdM6756 • Ospo , small cliff ; 45.57119° N, 13.8582° E; May 2010; De Mattia leg.; WdM6993 • Otlica ; 45.92822° N, 13.90918° E; 1986; De Mattia leg.; WdM6752 • Planina ; 45.82405° N, 14.24708° E; 2000; Zallot leg.; EZ0823 • Planina ; 45.82972° N, 14.25056° E; 2000; Zallot leg.; EZ0824 • Planina , Postojna; 45.83° N, 14.26056° E; 2009; Zallot leg.; EZ0826 • Podgorje ; 45.53872° N, 13.9449° E; 2000; De Mattia leg.; WdM6735 • Podgorje ; 45.5364° N, 13.9463° E; 2009; De Mattia leg.; WdM6735 • Podlešče-Bainsizza ; 46.05738° N, 13.72709° E; May 2009; De Mattia leg.; WdM6814 • Prešnica ; 45.56587° N, 13.94191° E; Mar 2009; De Mattia leg.; WdM6734 • Pri Cerkvi- Bainsizza ; 46.04133° N, 13.77584° E; 2009; De Mattia leg.; WdM6834 • Rakow Skocjan; 45.79467° N, 14.28948° E; 2010; Zallot leg.; EZ0838 • San Canzian (Škocjan); 45.66532° N, 13.99356° E; 2009; De Mattia leg.; WdM6754 • Senožeče ; 45.71421° N, 14.07856° E; 2009; De Mattia leg.; WdM6865 • 10 km S of Vrhnika; 45.88549° N, 14.26091° E; 2000; Zallot leg.; EZ0827 • Vrhnika, Močilnik ; 45.95591° N, 14.29268° E; 2009; Zallot leg.; EZ0829 .

Remarks

The original indication of the type locality is rather vague, since only a city in the Friuli-Venezia Giulia region, in the easternmost part of Italy is indicated. The closest to Trieste where we found the species is at “Val Rosandra”, 8 km north-east of the city. The fresh specimens collected there have shell features similar to those of the syntypes. We therefore consider them as topotypical.

Description

SHELL. The size of the shells is extremely variable (height 6.1–9.6 mm in the females) as well as their general morphology (see Fig. 28 ). Several populations are spotless whereas others have clear spots on the teleoconch. Depending on the population, the lip can be either poorly or even hugely developed. In lateral view, the body whorl, while approaching the aperture, may widen in various ways, depending on the population ( Fig. 4A : FF, AF, II). The H/W ratio is very variable and the slenderness of the shells in different populations varies accordingly.

FEMALE GENITALIA. There is a long, club-shaped seminal receptacle. In some cases there is a change of colour at its base, presumably indicating the starting point of the rather long distal oviduct. As shown in Table 5 , there is a considerable variability in the part of the seminal receptacle that is curved down and in the number of loops.

MALE GENITALIA. The inflated penis is longer than the body. The penial spermiduct is confined to the central part of the penis and gently twisted. The body spermiduct is straight and well defined.

Distribution

This species inhabits the eastern side of the province of Trieste in Italy, the southwestern part of Slovenia and the Istrian peninsula. It has also been found in several Croatian localities in the surroundings of Bakar and, quite far from its main range, on the Villacher Alps, in Austria (see Mildner 1997). The species has been erroneously reported for Albania (see Fehér & Erőss 2009).

Habitat preference

It is an obligate rock-dwelling species. Co. (Cl.) tergestinum is found in a variety of habitats, from open, exposed limestone cliffs to shady spots in deciduous and evergreen forests.

Remarks

According to Zilch (1958) and Alzona (1971) there are 3 subspecies of Co. (Cl.) tergestinum , viz. the nominate subspecies Co. (Clessiniella) tergestinum tergestinum ( Westerlund, 1878) , Co. (Clessiniella) tergestinum grahovanum (A.J. Wagner, 1897) and Co. (Clessiniella) tergestinum tortivum ( Westerlund, 1885) .

For the time being, we here synonymize these nominal taxa because the conchological features which supposedly characterize them, like measures, density and prominence of the ribs, and the structure of the lip, are population features without an obvious geographical pattern. There is no significant correlation between latitude and longitude of the locality of the sample and the character states that are mentioned in the original description of the so-called subspecies. Moreover, in the surroundings of Trieste, the type locality of the nominate subspecies, only populations with some ‘ tortivum ’ shell features, like the thin lip, can be found ( De Mattia & Prodan 2006).

Some of the populations have a peculiar shell morphology (see for instance Fig. 28E–F ); their taxonomical status should be investigated more thoroughly especially since the available molecular H3 analysis indicates that population “EZ0813” from Rasko Polje, corresponding to the specimen in Fig. 28E , stands apart from the others.

Figures

Fig. 1. Map of the sampling localities. Blue dots = Cochlostoma (Clessiniella) villae (Strobel, 1851); red dots = Co. (Cl.) stelucarum sp. nov.; green dots = Co. (Cl.) tergestinum (Westerlund, 1878); yellow dots = Co. (Cl.) waldemari (A.J. Wagner, 1897); orange dots = Co. (Cl.) anomphale Boeckel, 1939.

Fig. 3. Examples of protoconchs: the red dots mark the end of the protoconchs. A. Cochlostoma (Clessiniella) anomphale Boeckel, 1939 (EZ0034). A1. Co. (Cl.) anomphale (EZ0034): 1 = end of the first smooth part of the protoconch; 2 = end of the protoconch. B. Co. (Cl.) tergestinum (Westerlund, 1878) (EZ0799). C. Co. (Cl.) villae (Strobel, 1851) (EZ0885). D. Co. (Cl.) waldemari (A.J. Wagner, 1897) (WdM6697). E. Co. (Cl.) stelucarum sp. nov. (EZ0104).

Fig. 5. Genitalia in Clessiniella Zallot et al., 2015. A. Female genitalia (Cochlostoma (Clessiniella) tergestinum (Westerlund, 1878) (WdM6998)). 1 = ovary; 2 = visceral oviduct; 3 = proximal loop; 4 = loops of the visceral oviduct; 5 = seminal receptacle; 6 = distal oviduct; 7 = pedunculus of the bursa copulatrix; 8 = bursa copulatrix; 9 = copulatory duct; 10 = channel of the uterine gland; 11 = uterine gland. B. Male genitalia (Co. (Cl.) tergestinum (WdM7012)). 1 = anus; 2 = fold delimiting the sperm groove; 3 = sperm pocket; 4 = penial funnel; 5 = body spermiduct; 6 = penis with the internal spermiduct.

Fig. 14. The five species of Clessiniella Zallot et al., 2015. A–D. Picture of a female (top) and male (bottom) specimen from the type localities. A. Cochlostoma (Clessiniella) anomphale Boeckel, 1939. Vellach, Austria (EZ0991). B. Co. (Cl.) stelucarum sp. nov., Cornino, Italy (EZ0104). C. Co. (Cl.) tergestinum (Westerlund, 1878), Val Rosandra, Italy (EZ0840). D. Co. (Cl.) villae (Strobel, 1851), Mizzole, Italy (EZ0878). E. Specimens from a locality close to the type one: Co. (Cl.) waldemari (A.J.Wagner, 1897), Mt Klek, Croatia (EZ0905).

Fig. 15.Comparison of femalegenitalia.A. Cochlostoma (Clessiniella) anomphaleBoeckel, 1939.Vellach, Austria (EZ0991). B. Co. (Cl.) stelucarum sp. nov., Cornino, Italy (EZ0104). C. Co. (Cl.) tergestinum (Westerlund, 1878), Val Rosandra, Italy (EZ0840). D. Co. (Cl.) villae (Strobel, 1851), Mizzole, Italy (EZ0878). E. Co. (Cl.) waldemari (A.J.Wagner, 1897), Mt Klek, Croatia (EZ0905).

Fig. 16.Comparisonof male genitalia.A. Cochlostoma (Clessiniella)anomphaleBoeckel, 1939.Vellach, Austria (EZ0991). B. Co. (Cl.) stelucarum sp. nov., Cornino, Italy (EZ0104). C. Co. (Cl.) tergestinum (Westerlund, 1878), Val Rosandra, Italy (EZ0840). D. Co. (Cl.) villae (Strobel, 1851), Mizzole, Italy (EZ0878). E. Co. (Cl.) waldemari (A.J.Wagner, 1897), Tisovec, Croatia (WdM6750).

Fig. 28.Shell variability in Cochlostoma (Clessiniella) tergestinum (Westerlund, 1878).A. Mt Kobilica, Slovenia (WdM6849). B. Limski Kanal, Croatia (WdM6693). C. Dobratsch, Austria (EZ0799). D. Farjev Vrh, Slovenia (WdM6740). E. Rasko Polje, Croatia (EZ0813). F. Raša, Croatia (WdM6968). G. Val Rosandra, Italy (EZ840). H. Mala Učka, top, Croatia (WdM6794). I. Ilirska Bistrika, Slovenia (EZ0921). L. Permani, Croatia (WdM6708). M. Vrhnika, Slovenia (EZ0827). N. Near Bakar, Croatia (EZ0938). O. Mala Učka, Croatia (WdM6768). P. Mt Snežnik 1161, Slovenia (WdM7012).

Fig. 29.Variation of the female genitalia in Cochlostoma (Clessiniella) tergestinum (Westerlund, 1878). A. Pri Cerkvi, Slovenia (WdM6834). B. Brestovica, Slovenia (WdM6948). C. Dobratsch, Austria (EZ0799). D. Goriansko, Slovenia (WdM6950). E. Prešnica, Slovenia (WdM6734). F. Farjev Vrh, Slovenia (WdM6740). G. Rasko Polje, Croatia (EZ0813). H. Rasa, Croatia (WdM6968). I. Permani, Croatia (WdM6708). L. Meja-Bakarac, Croatia (WdM6951). M. Jakačici, Croatia (WdM6699). N. Drivenik, Croatia (WdM6714).

Fig. 30. Cochlostoma (Clessiniella) tergestinum (Westerlund, 1878), syntype at the Senckenberg Museum Frankfurt (SMF160676/7).

Fig. 34. Example of two populations of species of Clessiniella Zallot et al., 2015 which are impossible to distinguish without analyzing the male genitalia. Female shells. Top: Cochlostoma (Clessiniella) waldemari (A.J. Wagner, 1897), Polog-E of Čepovan, Slovenia (WdM6842). Bottom: Co. (Cl.) tergestinum (Westerlund, 1878), Jakačici, Croatia (WdM6699).

Fig. 4. Features of the shell of Clessiniella Zallot et al., 2015. A. Shape of the body whorl approaching the aperture. B. Strength of the spots on the shell (0 = spotless shell to 2 = really evident spots). C. Strength of the ribs (1 = weak ribs to 3 = really prominent ribs). D. Strength of the ribs on the external side of the body whorl approaching the aperture (W= smooth shell; I = intermediate; S = prominent ribs).