Hauffenia lozekiana, Haase & Grego & Erőss & Farkas & Fehér, 2021

Haase, Martin, Grego, Jozef, Erőss, Zoltán Péter, Farkas, Roland & Fehér, Zoltán, 2021, On the origin and diversification of the stygobiotic freshwater snail genus Hauffenia (Caenogastropoda: Hydrobiidae) with special focus on the northern species and the description of two new species, European Journal of Taxonomy 775, pp. 143-184 : 164-166

Hauffenia lozekiana sp. nov.

urn:lsid:zoobank.org:act:63FE4F3F-32A5-4F83-869F-C72B6E2D56AE

Figs 2 , 5 71a–b, 12A–C, 13A–B, 14A, 15A–C, 17A–B, 18; Tables 3–4

Diagnosis

The combination of valvatiform shell with eventually detached peristome and an only initially sculptured embryonic shell, a thin, yellow operculum without peg-like structure in the nucleus and the massive, trapezoidal penis, whose left side is flattened, distinguishes H. lozekiana sp. nov. from all other congeneric species. Only three diagnostic positions of the COI alignment were of type 1, a single of type 3, and 107 of type 4 ( Table 3 ). Uncorrected genetic distances to congeners ranged from 0.077 ( H. kerschneri ) to 0.133 ( H. steffeki sp. nov.; see Supp. file 3).

Etymology

Hauffenia lozekiana sp. nov. is dedicated to Vojen Ložek (26 Jul. 1925 – 15 Aug. 2020), renowned and influential Czech malacologist and paleontologist, who contributed significantly to Quaternary malacostratigraphy, Czechoslovakian zoogeography of mollusks and was the first to discover the genus Hauffenia in Slovakia.

Material examined

Holotype ( Fig. 12A–C ) SLOVAKIA • Bystrica Highlands , vicinity of Poniky/Oravce, Kalinovský prameň (Kalinovec); 48°42.027′ N, 19°15.952′ E; alt. 482 m; 4 Jan. 2014; J. Grego leg.; karst spring; NHMW 113638 . ( Fig. 5 71a–b)

Paratypes ( Fig. 13A–B ) SLOVAKIA • 5 specs; same collection data as for holotype; JG F1684 • 4 specs; same collection data as for holotype; NHMW 113639 • 2 specs; same collection data as for holotype; ZPE • 2 specs; same collection data as for holotype; 25 Jan. 2014; HNHM 105307 • 2 specs; same collection data as for holotype; JG F1649 • 2 specs; same collection data as for holotype; 18 May 2017; JG F1650 • 4 specs; same collection data as for holotype; 2 Jul. 2020; JG F1886 • 2 specs; same collection data as for holotype; NMBE 569388 • 2 specs; same collection data as for holotype; SMF 363255 • 2 specs; same collection data as for holotype; SMOPAJ 1/2021 • 2 specs; same collection data as for holotype; ZMH 140884 • 3 specs; same collection data as for holotype; 21 Dec. 2020; JG F1887 .

Description

SHELL ( Figs 12A–C , 13A–B , 14A ; Table 4 ). Valvatiform, maximum height measured 1.03 mm, maximum width 1.58 mm, on average twice as wide as high, with up to 2.75 whorls, final part of last whorl may be detached, fairly variable in shape with a coefficient of variation of 13.31% for the height/ width ratio; embryonic shell with 1.1–1.2 whorls, first 0.75 whorls wrinkled, sculpture then fading to become smooth; aperture almost round only slightly higher than wide, prosocline, lip continuous, not thickened; umbilicus wide.

OPERCULUM. Thin, chitinous, yellow, almost circular with central nucleus, the latter without peg or peglike modification.

EXTERNAL FEATURES. Epidermis without pigment, no eye spots visible, tentacles without particular ciliation.

MANTLE CAVITY. 9 gill filaments (N = 1), osphradium short, oval, behind middle of gill.

DIGESTIVE SYSTEM ( Figs 15A–C , 16 ). Radula with formula R 4-5 1 4-5/1 1, L 4-6 1 5-6. M1 23-29, M2 15-20 (N = 3); intestine forming a long loop in roof of mantle cavity, the loop is additionally coiled, its appearance seems to vary depending on the presence and number of fecal pellets.

FEMALE GENITALIA. Not observed; the only live collected female specimen was subadult, hence, the distal genitalia were not yet developed.

MALE GENITALIA ( Figs 17A–B , 18 ). Not observed except for kidney-shaped prostate and penis; penis massive, trapezoidal, left side flattened, small, brown, probably chitinous stylet anterior right near penial opening.

Habitat

The type locality is a small permanent karst spring emerging from the small karst massif of Drienok formed by Middle Triassic (Aegean–Ladinian) Wetterstein, Reifling and Gutenstein Limestones of the Silicikum Unit (Silica Nappe) at the contact zone to impermeable Early Triassic shales and sandstones of Szin and Bódvaszilas Members with a small discontinuous stripe of alluvial gravel at the bottom of the spring valley. The character of the type locality indicates the same habitat preference in the phreatic rhizosphere as discussed for H. kissdalmae .

Distribution

Known only from the type locality so far.

Conservation

There is only one known location and the area of occupancy is probably considerably smaller than 20 km 2. The combination of the restricted range and the threat imposed by the apparent trend of logging in the area around the type locality qualify for a threat assessment of Vulnerable (VU, D2) according to the IUCN Standards and Petitions Committee (2019).

Remarks

The genetic distances of H. lozekiana sp. nov. from the more widespread H. kissdalmae and the Austrian species suggest that it is a relict probably from the earlier colonization of the Hron River Valley ca 4.5 Ma ago (see Discussion).

Figures

Fig. 2. Localities in Slovakia (A) and Hungary (B). Abbreviation: LT = type locality.

Fig. 5. Type locality of H. lozekiana sp. nov. (71) and Dabarska Pećina, a locality of H. steffeki sp. nov. (72) (see Table 1).

Fig. 12. Holotypes. A–C. H. lozekiana sp. nov. (NHMW 113638). D–E. H. steffeki sp. nov. (NHMW 113640). Scale bar = 500 µm.

Fig. 13. Paratypes from type localities (SEM micrographs). A–B. H. lozekiana sp. nov. (NHMW 113639). C–D. H. steffeki sp. nov. (NHMW 113641). Scale bar = 500 µm.

Fig. 14. Protoconchs (SEM micrographs). A. H. lozekiana sp. nov., paratype (NHMW 113639). B. H. steffeki sp. nov., paratype (NHMW 113641). Scale bars = 100 µm.

Fig. 15. Radulae (SEM micrographs). A–C. H. lozekiana sp. nov. D–F. H. steffeki sp. nov. D. Type locality. E–F. Spring Krivina (locality 74 from Table 1). Scale bars: A = 10 µm; B–E = 2 µm; F = 3 µm.

Fig. 16. Schematic representations of intestinal loop configurations.

Fig. 17. Penes (SEM micrographs). A–B. H. lozekiana sp. nov. (different specimens). C–E. H. steffeki sp. nov. (one specimen). Arrow points at penial stylet, which is withdrawn in A and B. Scale bars: A–C = 50 µm; D = 10 µm; E = 2 µm.

Fig. 18. Penis of H. lozekiana sp. nov. Frontal view showing stylet. Scale bar = 50 µm.