Monacha pantanellii (De Stefani, 1879)

Pienkowska, Joanna R., Manganelli, Giuseppe, Giusti, Folco, Barbato, Debora, Kosicka, Ewa, Hallgass, Alessandro & Lesicki, Andrzej, 2020, Redescription of Monacha pantanellii (De Stefani, 1879), a species endemic to the central Apennines, Italy (Gastropoda, Eupulmonata, Hygromiidae) by an integrative molecular and morphological approach, ZooKeys 988, pp. 17-61 : 17

publication ID	https://dx.doi.org/10.3897/zookeys.988.56397
publication LSID	lsid:zoobank.org:pub:6806D201-2ABF-4A8C-B06C-A7A31CDF852D
persistent identifier	https://treatment.plazi.org/id/9F28FA85-571C-556E-9394-3A5E8A6CE89E
treatment provided by	ZooKeys by Pensoft
scientific name	Monacha pantanellii (De Stefani, 1879)
status

Treatment

Monacha pantanellii (De Stefani, 1879) View in CoL Figures 5-14 View Figures 5–14 , 15-22 View Figures 15–22 , 23-31 View Figures 23–31 , 37-40 View Figures 37–40 , 41-44 View Figures 41–44 , 45-48 View Figures 45–48 , 49-52 View Figures 49–52 , 53-56 View Figures 53–56 , 57-59 View Figures 57–59 , 60-63 View Figures 60–63

Helix pantanellii De Stefani, 1879: 40-41.

Monacha ruffoi Giusti, 1973: 533-537, pl. 6.

Diagnosis.

A species of Monacha (s. str.) (according to the subgeneric division proposed by Neiber and Hausdorf 2017) with vaginal appendix usually short and slender (having shape and size of a digitiform gland) inserted at mid vagina; proximal vaginal sac absent; penial flagellum long to very long; penial papilla with narrow space between external walls and central duct; central duct circular in transverse section, usually rather small in diameter, not joined by strips to external walls and with its lumen almost totally filled by large pleats.

Redescription.

Shell (Figs 5 View Figures 5–14 - 31 View Figures 23–31 ) dextral, sub-globose to globose, small to medium in size, variable in colour, sometimes (when colour is brownish yellow) with paler subsutural and peripheral bands, with 5¼ -6 slightly convex whorls separated by superficial sutures; aperture slightly prosocline, round to oval; peristome not reflected, thickened, with variably evident whitish callous rim lining the outer margin; umbilicus open, very small to small; protoconch and teleoconch smooth, with very faint scattered collabral growth lines. Shell dimensions: H: 10.3 ± 1.5 mm; D: 16.2 ± 2.3 mm (n = 45).

Radula not examined.

Female distal genitalia (Figs 37 View Figures 37–40 , 38 View Figures 37–40 , 41 View Figures 41–44 , 42 View Figures 41–44 , 45 View Figures 45–48 , 46 View Figures 45–48 , 49 View Figures 49–52 , 50 View Figures 49–52 , 53 View Figures 53–56 , 54 View Figures 53–56 , 57 View Figures 57–59 , 58 View Figures 57–59 , 60-63 View Figures 60–63 ; Table 7 View Table 7 ) include free oviduct, bursa copulatrix and its duct, digitiform glands, vagina and vaginal appendix. Free oviduct short and variably wide. Bursa copulatrix bean-like or pyriform with long wide duct. Vagina short to long and wide. Digitiform glands disposed on opposite sides of vagina in two groups of 1-3 tufts, each with 1-3 units. Vaginal appendix usually short (having shape and size of a digitiform gland) and inserted approximately half-way along the vagina.

Male distal genitalia (Figs 37 View Figures 37–40 - 63 View Figures 60–63 , Table 7 View Table 7 ) include vas deferens, flagellum, epiphallus and penis. Vas deferens very long and very slender. Flagellum long to very long and slender. Epiphallus long to very long and wide. Penis short and wide, enveloped by thin sheath, consisting of proximal portion (from start of penial sheath to base of penial papilla) and distal portion (from base of penial papilla to genital atrium). Penial papilla variable in shape (perhaps due to pre-mortem stress or spirit fixation), with apical opening, thick external walls and narrow space between external walls and central duct; central duct circular in section, usually rather small in diameter, not joined by strips to external walls of penial papilla and with its lumen almost totally filled with large pleats.

Genital atrium large, receiving vagina and penis, internally smooth or with variably developed longitudinal pleats.

Type locality.

"Sulla cima del Monte Fionghi al sud di Spoleto a circa mille metri sul livello del mare ", i.e., on the summit of Monte Fionchi, south of Spoleto, at an altitude of ca. 1000 m (municipality of Spoleto, province of Perugia), UTM references 32T UH 1726, Lat and Long: 42°40.455'N, 12°46.340'E.

Type material.

Probably lost.

Topotype sequences.

Sequences obtained from individuals from the type locality of M. pantanellii are designated as typical for this species: COI - MT380011-MT380018, 16S rDNA - MT376031-MT376039, ITS2 - MT376088-MT376094, H3 - MT385776-MT385785.

Etymology.

Named after Dante Pantanelli (1844-1913), Italian palaeontologist and geologist at the University of Modena. He published many papers on Miocene and Pliocene molluscs, some of which were co-authored by his friend Carlo De Stefani (1851-1924). He was also the secretary of the Italian Malacological Society and the editor of the Bullettino della Società Malacologica Italiana for many years ( Manganelli et al. 2017, with references).

Giusti’s species was named after Sandro Ruffo (1915-2010), a major Italian twentieth-century zoologist and director of the Museo Civico di Storia Naturale di Verona for many years ( Latella 2011).

Distribution.

Endemic to Umbria-Marche Apennines and Latium Sub-Apennines. It occurs from the Apennines of Gualdo Tadino in the north to the Aniene and Turano valleys in the south.

Ecology.

Mesophile species living among grass in open habitats such as grasslands, pastures, forest edges and clearings in hill and mountain areas.

Conservation.

Apparently common and widespread species within its range, but in some sites (e.g., Vallonina) it was no longer found during a field survey in the summer of 2019. Like other mesophilic species it could be sensitive to global warming.

Remarks.

This species was distinguished from Monacha cantiana on the basis of a few shell characters ("more depressed, more fragile and paler shell, with fine growth lines, less rounded opening and deeper umbilicus") and was disregarded by its author as an "extreme variety" of the former. Subsequently it was only reported in two catalogues by Westerlund (1889: 95) and Pilsbry (1895: 266) so that when Alzona prepared the catalogue of Italian non-marine malacofauna, they included it as a doubtful species ( Alzona 1971: 183).

On the contrary, our analysis showed that it matches a valid species, currently known as Monacha ruffoi , described from the Reatini mountains by Giusti (1973) as a Monacha species with a shell resembling that of cantiana , but with a much smaller vaginal appendix.

This is an unexpected result: indeed, De Stefani’s species is one of thousands of mollusc species established since the second half of the nineteenth century on the basis of very few shell features of no diagnostic value due to dramatic intra- and inter-population variability. In describing thousands of species and varieties, past authors hit on some that remained valid.