Achaiohydrobia Falniowski, 2021

Falniowski, Andrzej, Grego, Jozef, Rysiewska, Aleksandra, Osikowski, Artur & Hofman, Sebastian, 2021, A new genus and species of Hydrobiidae Stimpson, 1865 (Caenogastropoda, Truncatelloidea) from Peloponnese, Greece, ZooKeys 1037, pp. 161-179 : 161

Genus Achaiohydrobia Falniowski gen. nov.

Type species.

Achaiohydrobia moreana by monophyly.

Diagnosis.

Shell broad, ovate-conic with a few flat whorls, rapidly growing and separated by a moderately deep suture; female reproductive organs with prominent, massive swelling of the spiral of the oviduct; oval bursa copulatrix with the duct longer than the bursa, receptaculum seminis prominent but smaller than the bursa, with the duct slightly distinguishable; penis tapering, widened at the base, without any outgrowths (nonglandular lobes) and without the distal papilla.

Derivatio nominis.

The genus name refers to Achaia, one of the ancient names of Greece and the Greek people.

Remarks.

The tapering penis with its broad base distinguishes Achaiohydrobia from Hydrobia and Peringia . The lack of any non-glandular outgrowths (lobes) distinguishes it from Hydrobia , Peringia , and Ventrosia . The lack of the distal papilla on the penis distinguishes it from Salenthydrobia . The massive swelling of the long spiral renal oviduct differentiates Achaiohydrobia from all other genera besides Hydrobia . The molecular divergence between Achaiohydrobia and the other genera (p = 0.109-0.167 for mitochondrial COI) is typical of the genus-level in Hydrobiidae .