Two new camaenid land snails (Eupulmonata) from Central China

New camaenid genus and species from Zhejiang, East China (Eupulmonata, Helicoidea)

We report a new land snail species representing a new genus from the mountainous area of Zhejiang, China. The snail has a depressed shell with granules all over the surface. The soft part of the new taxon is characterized by the presence of a mantle lobe whose form is reviewed herein across a wide range of helicoid snails, the presence of a developed epiphallic papilla, and the absence of a penial sheath, a dart sac apparatus and a flagellum. As indicated by a molecular-based phylogeny (16S + ITS2), the new taxon is deeply nested in the eastern Asian camaenid genera and shows a close relationship with the camaenids distributed in Central China.

Land snail diversity in central China: revision of Laeocathaica Möllendorff, 1899 (Gastropoda, Camaenidae), with descriptions of seven new species

Central China harbors the native dart-sac-bearing camaenids Laeocathaica. The genus is revised and seven new species are proposed based on museum material and newly collected specimens. This work confirmed that most Laeocathaica species have restricted habitats. The comparison of the dart sac apparatus among the dart-sac-bearing camaenid genera indicated the importance of the presence of the proximal accessory sac that might be analogous to the membranous/muscular sac surrounding the proximal dart sac and/or the distal region of the vagina near the atrium, which also plays a significant role in the diagnosis of Laeocathaica species based on its number, symmetry and position on the dart sac. Species with similar shell morphology were studied using geometric morphometric methods to detect variations in shell shape. A molecular phylogenetic analysis based on 16S and ITS2 sequence data of partial Laeocathaica species and many other dart-sac-bearing taxa suggested that Laeocathaica might be monophyletic. Furthermore, the present phylogeny indicated that Stilpnodiscus, Cathaica, Bradybaena, and Pseudobuliminus might be polyphyletic and therefore the taxonomy of dart-sac-bearing camaenids in this region requires a thorough revision. This work reconfirms that the Southern Gansu Plateau is important as a hotspot for malacodiversity conservation on the Chinese mainland.

Convergent evolution of

East Asian terrestrial snails of the family Camaenidae Pilsbry, 1895a are diverse in terms of genus and species numbers, shell morphology and mode of living. This family also includes colourful conical arboreal snails that traditionally have been assigned to the genus Amphidromus Albers, 1850. Yet, the present study shows that, despite their deceiving conchological similarity, some of these East Asian arboreal snails do not belong to the genus Amphidromus or the subfamily Camaeninae Pilsbry, 1895a. The presence of a dart complex comprising a mucous gland, a dart sac, an accessory sac and a proximal accessory sac, along with a pronounced penial caecum and molecular phylogenetic analyses revealed that former ‘Amphidromus’ dautzenbergi, ‘A.’ roemeri and ‘Camaena’ mirifica, and one additional new species belong to Aegistohadra Wu, 2004 (subfamily Bradybaeninae Pilsbry, 1934). Aegistohadra dautzenbergi, comb. nov. and Aegistohadra roemeri, comb. nov. are conical with colourful spiral bands, whereas Aegistohadra mirifica, comb. nov. and Aegistohadra zhangdanae, sp. nov. are heliciform to conical with colourful, variegated spiral and transverse banding patterns. DNA sequence analyses also revealed that each variety of Aegistohadra dautzenbergi could not be differentiated by mitochondrial (cytochrome c oxidase subunit I and 16S rRNA) gene fragments. The phylogenetic position of Aegistohadra within the East Asian camaenids revealed that the similar appearance in shell morphology, microhabitat use and diet to arboreal snails in the genus Amphidromus is homoplastic. Moreover, the presence or absence of a dart complex is also homoplastic and is unsuitable for suprageneric classification. By contrast, the presence of a flagellum and a penial caecum is useful for the suprageneric classification.

Revision of the " Chloritisdelibrata (Benson, 1836)" group (Gastropoda, Stylommatophora, Camaenidae)

Chloritisdelibrata (Benson, 1836), known from northeastern India, was believed to have three varietal forms, sometimes mentioned as subspecies: C.delibratavar.khasiensis (Nevill, 1877) and C.delibratavar.fasciata (Godwin-Austen, 1875) from the Khasi Hills, India, and C.delibratavar.procumbens (Gould, 1844) from Dawei in Myanmar. The reproductive anatomy of the latter form is known and does not match with those of any continental camaenid genera, but does with that of the newly examined Chloritisplatytropis Möllendorff, 1894 from Thailand. The latter species is conchologically similar to Bouchetcamaenahuberi Thach, 2018 (synonym of Helixfouresi Morlet, 1886), which is the type species of the genus Bouchetcamaena Thach, 2018. Thus, Bouchetcamaena can provisionally host the entire Chloritisdelibrata -group with the exception of var. fasciata, which is transferred to Burmochloritis Godwin-Austen, 1920 due to the multiple reddish bands on its shell. The examination of shells deposited in the Natural History Museum, London revealed that seven morphologically distinguishable forms are present, which are accepted here as representing distinct species. Four new species are described from India: Bouchetcamaenafoveata Páll-Gergely sp. nov., B.fusca Páll-Gergely sp. nov., B.raripila Páll-Gergely sp. nov., and B.subdelibrata Páll-Gergely sp. nov.

Descriptions of four new dextral land snails of the genus Camaena (Gastropoda, Eupulmonata, Camaenidae) from south China

In this study, four new dextral camaenid from China are reported, based on shell morphology, reproductive system anatomy, and molecular phylogenetic analyses: Camaenafuningensis Zhou, Wang & Lin, sp. nov., Camaenagaolongensis Zhou, Wang & Lin, sp. nov., Camaenamaguanensis Zhou, Wang & Hu, sp. nov., and Camaenayulinensis Zhou, Wang & Hu, sp. nov. Detailed descriptions of the morphological characteristics including shells and genitalia, DNA sequences, and living environments of the four new species are provided, with further comparisons with congeners.

Jawless land snail Sinorachis, a new bradybaenine genus from China (Eupulmonata, Camaenidae)

A new land snail species that represents a new genus is reported from Hubei, China. The snail has a conical shell with pits and/or granules on embryonic whorls and a smooth teleoconch with straight peristome. The head of the animal has a developed wart. The mantle lobe is only developed on the left side. At the front of the buccal mass there is no chitinous jaw that is without exception seen in Chinese camaenids. Its radular teeth are usually slender and tongue-shaped, not typical in bradybaenine snails. The genital system is typical of Bradybaeninae and is characterized by the absence of a membranous sac surrounding the terminal genitalia, penial caecum or flagellum; a well-developed penis sheath; a symmetrical dart sac apparatus; and one distally branched mucous gland. The new species Sinorachisbaihu Wu & Chen, gen. and sp. nov., is assigned to the type species of the new genus, in which all the known Chinese Rachis species are included. Thereby, the new genus is composed of three species, namely Sinorachisonychinus (Heude), comb. nov., Sinorachisaureus (Heude), comb. nov. and the new species.

New insights in Trichochloritis Pilsbry, 1891 and its relatives (Gastropoda, Pulmonata, Camaenidae)

The genus Bellatrachia Schileyko, 2018 was described based on a specimen identified as Helix (Chloritis) pseudomiara Bavay & Dautzenberg, 1909. We concluded that the examined specimen is not that species, but Helixcondoriana Crosse & Fischer, 1863. Therefore, (1) the type species of Bellatrachia must be replaced with Helixcondoriana; (2) the species Helix (Chloritis) pseudomiara must be re-allocated to the genus Trichochloritis; (3) the erroneous treatment of the genus Trichochloritis by Schileyko (2007) needs to be corrected through the description of a new genus, Dentichloritisgen. nov. based on Helixbrevidens Sowerby I, 1841. In addition, Chloritismicrotricha Möllendorff, 1898 is treated as a synonym of Helixcondoriana, and further information on the genitalia of Chloritis (?) bifoveata (Benson, 1856) is presented.