Helicopsis persica, Hausdorf, Bernhard & Bössneck, Ulrich, 2016

Hausdorf, Bernhard & Bössneck, Ulrich, 2016, Helicopsis persica n. sp. from northern Iran (Gastropoda: Geomitridae), Zootaxa 4066 (2), pp. 194-200 : 198

Helicopsis persica n. sp.

Shell ( Fig. 1–3 ). Disc-like to depressed conical; with 4.5–5 strongly inflated whorls; body-whorl sharply keeled; protoconch smooth; teleoconch with coarse ribs (12–17 per 5 mm of the body whorl); whitish with corneous bands or zones; aperture lemon-shaped; upper insertion of the peristome not or hardly descending towards the aperture; peristome not expanded, with an internal rib; umbilicus slightly eccentric, measuring 14–18% of the shell diameter.

Measurements (n = 27): shell diameter: 9.3–12.2 mm, mean 10.6 ± 0.8 mm; shell diameter at third whorl: 4.0– 5.4 mm, mean 4.8 ± 0.4 mm; shell height: 5.3–7.7 mm, mean 6.4 ± 0.6 mm; shell diameter/shell height: 1.47–1.88, mean 1.66 ± 0.11.

Genitalia ( Fig. 6–7 ). The penial papilla is conical. The outer layer of the penial papilla is laterally attached to the penis wall so that a cavity is separated in the proximal part of the penis. There are also a few small folds at the inner penis wall near the atrium that partly extend into the vagina. The penial nerve branches off from the cerebral ganglion. The part of the epiphallus distal of the penial retractor (holotype 0.7 mm, paratype 0.7 mm) is only indistinctly delimited against the penis (1.6 mm, 1.4 mm). The part of the epiphallus proximally of the penial retractor (4.2 mm, 5.1 mm) is 2.4–2.6 times as long as the short flagellum (1.5 mm, 2.1 mm). The dart apparatus consists of two broad symmetrical dart sacs and two narrow accessory sacs. The two counterparts are connected across the inflated vagina by bands of connective tissue. There are four deeply ramified glandulae mucosae. The openings of the dart sacs into the vagina are bordered by broad pilasters. The pedunculus is short and broad. The bursa of the bursa copulatrix is oval.

Remarks. The two symmetrical dart and accessory sacs and the lateral attachment of the outer layer of the penial papilla at the penis wall separating a cavity in the proximal part of the penis indicate that the new species can be classified in Helicopsis . The classification of Helicopsis persica in Helicopsis was tentatively confirmed by a preliminary phylogenetic analysis based on mitochondrial cox1 sequences ( Fig. 8 ).

Helicopsis persica differs from Helicopsis aelleni Hausdorf, 1996 ( Fig. 4 ) from northern Iran in the sharply keeled and coarsely ribbed shell with a narrower umbilicus. The shell of Helicopsis persica is somewhat similar to Helicopsis retowskii (Clessin, 1883) from Crimea ( Fig. 5 ). It differs from that species in the on average more coarsely ribbed shell with more strongly arched whorls on the upper side resulting in a gradated spire, an usually narrower umbilicus and a relatively shorter flagellum: ratio proximal epiphallus: flagellum = 2.6 in Helicopsis persica versus 1.9–2.4 in Helicopsis retowskii (according to figures in Hesse, 1934; Hudec, 1972; Schileyko, 1978 and Gural-Sverlova, 2012; but note that Gural-Sverlova, 2012: Table 1 indicated a larger variation in Helicopsis retowskii ).

Type material. Iran, Province Māzandarān: Marzanābād, calcareous grassland at the slope to the Chalus river, 670 m alt., 36.417°N 51.267°E (holotype ZMH 79888, leg. U. and K. Bössneck 0 1.05.2010, shell diameter = 10.6 mm, shell height = 6.0 mm; paratypes SMF /4; UBE/12; ZMTI /4; ZMH 79889/6).

Type locality ( Fig. 9 ). Iran, Province Māzandarān: Marzanābād, calcareous grassland at the slope to the Chalus river, 670 m alt., 36.417°N 51.267°E.

Distribution ( Fig. 10 ). Helicopsis persica is known only from the valley of the Chalus river at Marzanābād in the province Māzandarān in northern Iran.

Etymology. This species is named after the Latin name of Iran, Persia ( persica , used as an adjective).

Figures

FIGURE 8. Bayesian 50 % majority consensus tree based on mitochondrial cox 1 sequences. Numbers at the nodes refer to posterior probability values (right) obtained from the Bayesian analysis and bootstrap support values (left, if> 50) from the maximum likelihood analysis.

FIGURE 9. Type locality of Helicopsis persica n. sp. at the slope to the Chalus river near Marzanābād (Province Māzandarān, Iran).

FIGURE 10. Distribution of Helicopsis persica n. sp. (square) and Helicopsis aelleni Hausdorf, 1996 (dots) in Iran.

FIGURES 1 – 5. Shells of Helicopsis species. 1 – 3, Helicopsis persica n. sp., Iran, Province Māzandarān: Marzanābād. 1, Holotype (ZMH 79888). 2 – 3, Paratypes (ZMH 79889). 4, Helicopsis aelleni Hausdorf, 1996, Iran, Province Semnan: S of Chashm (= Djatschm) (paratype SMF 64029). 5, Helicopsis retowskii (Clessin, 1883), Crimea: Sevastopol, Balaklava (ZMH 24648). Scale bar = 5 mm for Figs. 1 – 3, 5, and 10 mm for Fig. 4.

FIGURES 6 – 7. Genitalia of Helicopsis persica n. sp., Iran, Province Māzandarān: Marzanābād. 6, Holotype (ZMH 79888). 7, Inner structure of the distal parts of the genitalia (paratype ZMH 79889). Scale bar = 1 mm.