Xeropicta krynickii (Krynicki, 1833)

Mattia, Willy De & Pešić, Vladimir, 2014, Xeropicta (Gastropoda, Hygromiidae) goes west: the first record of X. krynickii (Krynicki, 1833) for Montenegro, with a description of its shell and genital morphology, and an additional record of X. derbentina (Krynicki, 1836) for Italy, Ecologica Montenegrina 1 (4), pp. 193-200 : 195

Xeropicta krynickii (Krynicki, 1833)

Montenegrin populations

Shell ( Figs. 25­26 ). Dextral, subglobose to depressed, moderately robust; protoconch light brown; teleoconch creamy to light yellowish in colour, with six fine, interrupted bands visible only on lower side of the last whorl; a white continuous band is present along the last whorl; external surface of teleoconch waxy with well­defined, irregularely spaced growth lines; spire conical to slightly raised, with 4⅓ ­ 4 ¾ regularly growing, convex whorls, last whorl large and swollen, only moderately descending near aperture; umbilicus open, wide about ¼ of the maximum shell diameter; sutures deep; aperture rounded to moderately elliptical, periscope interrupted, never reflected at external, seldom with a thin whitish thickening on the palatal inner margin.

Shell dimensions diameter 15.2± 0.8 mm (range 14.3–16.3 mm); height 9.2± 0.9 mm (range 8.6–9.4 mm) (n=6). Ratio D/H 1.6.

Genitalia ( Figs. 1­12 ). The proximal part of the vagina has 10­14 digitiform (sometimes branched) glands, disposed in four tufts of 2­4 units. The dart­sac complex, entering the distal vagina on opposite sides (2+2 dart­sac complex), consists of two proximal, club­like, longer, dart­bearing, and two distal, club­like, shortest, dartless stylophores. Cavities of each of the 4 stylophores open almost independently into the vagina. The penial flagellum is moderately long and slender. The epiphallus is roughly three times longer than the flagellum. The penis is approximately half as long as epiphallus, without any penial sheath. It has a slender, smooth, penial papilla with a circular apical opening. The penial papilla has an outer sheath and presents a large, extended corpus cavernosus ( Fig. 5 ). The genital atrium contains a slender and conical penial appendage, which is usually twice as long as the penis. A large crest­like structure develops from the tip of this appendage and extends to the atrial aperture while gradually increasing in height (fig. 3). A second smaller, lobated crest­like structure can be found in this appendage, parallel to the main one, situated on its right.

Greek population

Figures 26 and 27 depict the shell of a specimen of X. krynickii from Livadia (Sterea Ellada, Mainland Greece). In all investigated specimens from Greece (n=18) the width of the umbilicus is about one fifth that shell. This ratio can also be seen in, amongst others, De Mattia (2007: 11) and Welter­Schultes (2012: 571). In the genital anatomy, some differences from Montenegrin specimens can be detected as regards the morphology of the penial papilla and the 2+2 stylophores. Greek specimens constantly show a penial papilla with lateral opening and much shorter proximal stylophores ( Figs. 4, 7 , 23 , and 24).

Figures

Figures 25­28. 25­26 shells ofXeropicta krynickiifrom Podgorica, Montenegro; 27 shell ofX. krynickii from Livadia (Beozia, Greece); 28 shell ofX. derbentina from Trieste (Italy).

Figures 1­9. Genitalia of Xeropicta krynickii from Podgorica, Montenegro. 1­2 whole genitalia, gonad excluded; 3 inner structureof distal genitalia; 4 dart sac complex; 5 section of penial papilla; 6 section of vagina; 7 penial papilla; 8 digitiform glands; 9 inner structure of epiphallus.

Figures 10­13. 10­12 genitalia and jaw ofXeropicta krynickiifrom Podgorica, Montenegro. 10 mantle edge; 11 first hermaphrodite duct; 12 jaw; 13 whole genitalia, gonad excluded, ofXeropicta derbentina from Trieste (Italy).

Figures 14­24. Genitalia of Xeropicta krynickii from Livadia (Sterea Ellada, Greece). 14 whole genitalia, gonad excluded; 15 inner structure of distal genitalia; 16 section of penial papilla; 17 section of epiphallus; 18 section of distal stylophore; 19 section of vagina; 20 digitiform glands; 21 mantle edge; 22 first hermaphrodite duct; 23 penial papilla; 24 dart sac complex.