Anauchen grandiportus Gojšina, Grego & Páll-Gergely, 2025

Gojšina, Vukašin, Hunyadi, András, Sutcharit, Chirasak, Tongkerd, Piyoros, Auffenberg, Kurt, Grego, Jozef, Vermeulen, Jaap J., Reischütz, Alexander & Páll-Gergely, Barna, 2025, A new start? Revision of the genera Anauchen, Bensonella, Gyliotrachela and Hypselostoma (Gastropoda, Eupulmonata, Hypselostomatidae) of Southeast Asia with description of 46 new species, ZooKeys 1235, pp. 1-338 : 1-338

Anauchen grandiportus Gojšina, Grego & Páll-Gergely sp. nov.

Figs 10 F , 18 , 37

Type material.

Holotype. Laos • 1 empty shell (SH: 1.71 mm, SW: 1.92 mm); Khammouane Province, NE foot of Mount Pha Soung , caverns among slope boulders; 17°33.108'N, 104°52.301'E; 08 Feb. 2017; J. Grego leg.; CUMZ 14428 .

Type locality.

Laos, Khammouane Province, NE foot of Mount Pha Soung, caverns among slope boulders; 17°33.108'N, 104°52.301'E.

Diagnosis.

Shell conical-ovoid, teleoconch radially and not spirally striated. Last whorl not detached from the penultimate and slightly descending. Aperture large, with seven weak barriers sitting on the peristome edge. Umbilicus narrow.

Description.

Shell brown, conical-ovoid with deep suture and bulging whorls. Whorls 3.25, rounded, regularly increasing. Protoconch consists of slightly> 1 whorl, finely pitted, its terminal part with ~ 12 equidistant spiral striae. Teleoconch with inconspicuous, irregular growth lines and finely dimpled (pasty), spiral striation absent. Last whorl rounded, adnate to the penultimate and slightly descending near the aperture (~ 15 ° compared to the shell axis), aperture slightly prosocline to shell axis in lateral view. Aperture conspicuously large to the shell size, parietal part adnate onto penultimate whorl forming a weak callus. Peristome slightly expanded but not reflected. Altogether seven apertural barriers could be found, all being blunt, knob-like, situated on peristome edge, their homologies with traditionally recognised barriers somewhat questionable. Parietal lamella is the largest, but still weak. Suprapalatal and upper palatal plicae situated close to each other, after some distance the next plica is the lower palatal. Lower palatal, basal, subcolumellar, and columellar situated in approximately equal distance from one another, gap between columellar and parietal is approximately as large as between parietal and the suprapalatal. There is a very slight thickening next to lower palatal plica, although it is questionable whether it would develop into a barrier. Surfaces of all apertural barriers are very finely granulated. Sinulus wide but low, not strongly isolated from the rest of the aperture. Umbilicus narrow, elongate, only shows body whorl.

Differential diagnosis.

Anauchen grandiportus sp. nov. differs from all other species assigned to Anauchen on the basis of the seven small, marginal denticles and the greatly enlarged aperture.

Measurements

(in mm, n = 1). SH = 1.92; SW = 1.71, AH = 0.96, AW = 0.87.

Etymology.

The specific epithet refers to the relatively large aperture when compared to the shell size.

Distribution.

This species is known only from the type locality.

Figures

Figure 10. Synoptic view of the species belonging to the genus Anauchen A A. angthongensis B A. banmiensis C A. crassus sp. nov. D A. eotvosi E A. evanidus sp. nov. F A. grandiportus sp. nov. G A. huaykhakang H A. informis informis I A. informis parcedentata J A. jokaii sp. nov. K A. kozari L A. messageri M A. obesus sp. nov. N A. picasso sp. nov. O A. rochebruni P A. turritus sp. nov. Q A. utaithaniensis.

Figure 18. Anauchen grandiportus Gojšina, Grego & Páll-Gergely, sp. nov., holotype (CUMZ 14428) A – D shell E enlarged protoconch view F, G enlarged view of the surface of the last whorl.

Figure 37. Distribution of species belonging to the genus Anauchen.