Valvata kournasi, Glöer & Hirschfelder, 2019

Glöer, Peter & Hirschfelder, Hans-Jürgen, 2019, New Freshwater molluscs from Crete, Greece (Gastropoda: Hydrobiidae, Bythinellidae, Valvatidae), Ecologica Montenegrina 20, pp. 10-23 : 18-21

Valvata kournasi n. sp. ( Figs. 37-42 )

Type material: Holotype ( ZMH 140040 ): Shell height 2.6 mm, shell width 5.0 mm . Paratypes: ( ZMH 140041 ) , coll. Hirschfelder (9 + 1 juv.).

Type locality: Greece, Nómos Chaniá , outflow of Lake Kournas, 3 km southeast of Georgioúpoli, alt. 19 m asl., 11.10.2014 Andrea and Hans-Jürgen Hirschfelder leg. ( Figs. 44-46 ) .

Etymology: V. kournasi n. sp. is named after the type locality (Lake Kournas).

Description:

Shell: The horn-colored shell has 3.5 circular whorls with a low spire and a blunt apex. The surface is densely covered by regular-silky ribs. The umbilicus is wide, shell diameter to diameter of umbilicus about 4: 1. The aperture is circular and slightly angulated at the top. Shell height up to 2.6 mm, diameter 5.0 mm.

Animal: unknown.

Differentiating characters: From the most similar Valvata macrostoma the new species differs in the narrower umbilicus and the slight angle at the top of the aperture which is missing in V. macrostoma .

Distribution: V. kournasi n. sp. is probably endemic to Lake Kournas.

Remarks: Only empty shells could be found in the overflow of the lake. The overflow area was totally dry during sampling time in autumn. Other mollusc species found with V. kournasi n. sp. were Heleobia maltzani ( Westerlund, 1886) , Planorbis atticus Bourguignat, 1852 , Radix labiata (Rossmässler, 1835) and Theodoxus saulcyi (Bourguignat, 1852) ( Fig. 46 ). V. kournasi n. sp. was the rarest one.

Figures

Figures 37-42. Comparison of two similar Valvata spp. 37-39: Valvata macrostoma (Hamburg), 40-42: Valvata kournasi n.sp. (Crete, Lake Kournas).

Figures 44-46. Lake Kournas, type locality of Valvata kournasi n. sp.. 45: Overflow of Lake Kournas which was completely dry during sampling time, 46: deposit of shells at the overflow where Valvata kournasi n. sp. was also found.