Maroccoarganiella touarguii Ghamizi et Falniowski 2024, sp. nov.

Maroccoarganiella touarguii Ghamizi et Falniowski, sp. nov.

urn:lsid:zoobank.org:act: A1793C4D-C60C-4DC5-9BB0-0229A8BBD8CD

GenBank no. for COI: PP079487–PP079489

Holotype. Ethanol-fixed specimen (Fig. 5A), Well 2 Bouregreg2, 33°13’49”N; 5°37’10”W, a well located in an agricultural plot serving for market gardening and olive groves, water used for irrigation, rudimentary protection by pieces of jujube bushes (Locality P10: Table 1, Fig. 1 and 2C), leg. M. Ghamizi, 12 April 2022.

Paratypes. Ethanol-fixed specimens: locality P9 (Table 1): A131 (Fig. 5B) sequenced, five specimens in the collection of MHNM (Muséum d’Histoire Naturelle de Marrakech), voucher number MHNM22 ZTMH60; locality P10 (Table 1, Fig. 2C): A132 (Fig. 5C) sequenced, 20 left in the collection of MHNM voucher numbers MHNM22 ZTMH61; locality P11 (Table 1, Fig. 3A):A133 (Fig. 5D) sequenced, three specimens left in the collection of Jagiellonian University. Four specimens left in the collection of MHNM voucher numbers MHNM22 ZTMH62.

Diagnosis. Minute valvatiform hydrobiid gastropod with hardly visible spire and circular aperture below the half of height of body whorl, neither eyes nor pigment, flat and massive, broad penis with broad and not prominent outgrowth on its right side.

Description. Shell (Fig. 5) minute, 0.51–0.69 mm high, 1.12–1.30 mm broad, valvatiform, formed by 2½ rapidly growing whorls, separated by shallow suture and forming low and narrow, proportionally minute spire. Umbilicus moderately wide, with older whorls visible inside. Body whorl growing slowly, adjacent to symmetrical, circular aperture. Peristome continuous. Shell thin-walled, whitish and translucent, glossy, growth lines nearly invisible. Shell measurements: Table 4, Fig. 6.

Soft parts morphology and anatomy. No eyes, body with no pigment. Penis (Fig. 7A) straight, broad, flat and massive, proximally broadened, distally triangularly sharpened, a broad and not prominent outgrowth distally on its right side. Female reproductive organs unknown.

Etymology. The species name dedicated to a deceased colleague that participated in the field collection: Professor Touargui member of AESVT Khemisset.

Differential diagnosis. The shell and the penis resemble the ones of Italian Arganiella pescei Giusti et Pezzoli, 1980 (Giusti & Pezzoli 1980, Delicado et al. 2021). The Moroccan Ainiella Taybi, Glöer et Mabrouki, 2022 (Taybi et al. 2022c), and Rifia yacoubii Ghamizi, 2020 differ in the outgrowth on the left side of the penis (Ghamizi 2020), absent in Maroccoarganiella. Islamia Radoman, 1973 with its bi-lobed penis (Radoman 1973) is evidently different. From among the Iberian valvatiform Hydrobiidae (Delicado et al. 2019) similar shell can be found in Iberhoratia Arconada et Ramos, 2007 (Arconada et al. 2007), but the penis in Iberhoratia has conspicuous outgrowth on its left side.Another Iberian valvatoid genus: Corbellaria Callot-Girardi et Boeters, 2012 has similar shell but its penis also bears prominent outgrowth (Ramos et al. 2000, Boeters et al. 2019). The Moroccan genera with the penis without outgrowth: Ifrania Glöer, Mabrouki et Taybi, 2020 (Glöer et al. 2020b) and Pikasia Taybi, Glöer et Mabrouki, 2021 (Taybi et al. 2021) have shells with lower and less circular aperture, and their penes do not resemble the broad and flat one of Maroccoarganiella. Moroccan Fessia Glöer, Mabrouki et Taybi, 2020 (Glöer et al. 2020b) has the shell with much higher spire, lower and somewhat oval aperture, and more slender penis; also the eyes and pigmentation of the body is characteristic of Fessia Glöer, Mabrouki et Taybi, 2020 (Glöer et al. 2020b), but not of Maroccoarganiella, although this troglomorphic adaptation is facultative and easily gained or lost (Culver & Pipan 2009). In Menzella timedrinensis Mabrouki, Glöer et Taybi, 2023 the shell is strikingly different than in Maroccoarganiella, globular with higher spire, some of the paratypes illustrated by Mabrouki et al. (2023) could be classified rather as trochiform, not valvatiform following Hershler & Ponder (1998). In Menzella timedrinensis there are eyes and pigmentation, also on the penis, which is bent, unlike our Maroccoarganiella.