Aulacospira pluangtong Panha & Burch, 2004

Dumrongrojwattana, Pongrat & Tanmuangpak, Kitti, 2020, The terrestrial microsnail genus Aulacospira Moellendorff, 1890 (Eupulmonata, Stylommatophora, Hypselostomatidae) in Thailand with key to Thai species, ZooKeys 980, pp. 23-42 : 23

Aulacospira pluangtong Panha & Burch, 2004 Figure 4A-D

Aulacospira pluangtong Panha and Burch 2004: 64, fig. 5.

Type locality.

Thailand, Pluangtong Mountain, an isolated limestone hill of Chonburi Province; 13°11'50"N, 101°34'49"E.

Material examined.

ZRCBUU 357 (3 shells); Thailand, Khao Mee Mountain, an isolated limestone hill of Chonburi Province; 13°09'02.7"N, 101°35'34.4"E; 15.x.2016; leg. Dumrongrojwattana, P.

Measurements.

H = 1.75-1.82 mm, W = 1.82-1.93 mm.

Diagnosis.

Shell minute; spire high; brownish. Protoconch smooth; teleoconch smoothish, with uneven growth striae. Final part of the last whorl free and projecting downward; peristome not expanded; aperture with four teeth, parietal and colummellar lamellae, and the upper and lower palatal plica.

Radula.

As in A. depressa (Fig. 4B ).

Genital system.

Atrium shorter than vagina. Penis longer than epiphallus, with anterior portion a slender tube. Epiphallus connected to distal end of penis. Epiphallus glossy white, longer than vas deferens, with its anterior portion slender and cylindrical, its central portion slender and more bulging than posterior portion. Epiphallic flagellum absent. Epiphallic retractor caecum rounded and bulbous, attached to posterior portion of epiphallus. Vas deferens very long, slender, entering epiphallus apically. Vagina and free oviduct cylindrical, with vagina shorter than free oviduct. Gametolytic sac very long and cylindrical, with anterior portion connecting vagina and free oviduct and posterior portion with curved knob. Uterus long and cylindrical, with very thin prostate gland adhering to it. Hermaphroditic duct loosely convolute. Albumen gland large and yellowish. Dart apparatus absent (Fig. 4C, D ).

Distribution.

This species is only known from the limestone hills in Botong District, Chonburi Province, eastern Thailand (Fig. 1 ).

Figures

Figure 1. Distribution map of Aulacospira spp. in Thailand: 1 A. depressa 2 A. khaopratun 3 A. panhai 4 A. khaobote 5 A. lampangensis 6 A. smaesarnensis 7 A. pluangtong 8 Aulacospira tekavongae sp. nov. 9 Aulacospira nudtadhirai sp. nov. 10 Aulacospira vanwalleghemi sp. nov.

Figure 4. A-D Aulacospira pluangtong (ZRCBUU 357) A shell B radula C, D genital system E-H Aulacospira nutadhirai sp. nov. E holotype (ZRCBUU 0391) F radula G, H genital system.