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The metacercarial infections of door snails (Gastropoda: Clausiliidae) with unknown species of the genus Brachylaima (Trematoda: Brachylaimidae) have recently been reported in eastern Honshu and Kyushu, Japan. A large scale snail survey was carried out to clarify their taxonomic status. From the period of 2015 to 2020, a total of 1239 land snails (768 door snails and 471 others) were collected from 32 localities in Honshu, Shikoku, and Kyushu. The resulting trematode isolates were identified as Brachylaima sp. by mitochondrial DNA barcoding. The sporocysts were found only a few from Megalophaedusa sublunellata (Clausiliidae), Tauphaedusa subaculus (Clausiliidae), and Aegista trochula (Camaenidae), while the metacercariae were frequently detected from 14 species of Clausiliidae and 2 species of other families. Although Brachylaima sp. showed a broad range of intermediate hosts, door snails seem to be very important to drive the life cycle. The gravid adults of Brachylaima sp. was experimentally raised from metacercariae using immunosuppressed mice. Morphological, phylogenetical, and ecological considerations prompted us to propose Brachylaima phaedusae n. sp. for this unknown species. The definitive hosts of the new species are completely unknown. The wide geographic distribution and high genetic diversity of the new species suggest a possibility that the definitive host is ground-foraging birds, which prefer door snails.

Prey-tracking behavior is common in snail-killing predators, but in the family Lampyridae, this behavior has been validated in only a single species even though this Coleopteran family includes many specialist snail predators. The endemic firefly Pyrocoelia atripennis is a major snail-killing predator in the Yaeyama Islands of Japan, and the larvae often climb on the trees and grasses at night. This tree-climbing behavior is relevant to larval food choices and anti-predatory defenses of land snails. This study examined whether lampyrid larvae can track snail mucus trails and examined larval prey preferences using alternative choice experiments. In addition, predation trials were conducted to evaluate which snail species are potential prey. P. atripennis larvae significantly selected mucous trails over distilled water or control (no-trail) treatments. In addition, a semi-arboreal species was preferred over a ground-dwelling species. In predation trials, the larvae preyed on five out of 10 endemic snail species, all of which were semi-arboreal or arboreal species. Ground-dwelling Cyclophoridae and Aegista species have effective anti-predatory defenses consisting of an operculum or “foamy-lid” that fills the shell aperture. Whether the prey has a lid affects the predation success of lampyrid larvae, and larval tree-climbing behavior may be an adaptation used to search for semi-arboreal and arboreal land snails that lack defensive lids. Furthermore, snail mucus left on the plant stem may help the lampyrid larvae to locate their prey.

Aegista hiroshifukudai n. sp. from Yamaguchi Prefecture, the Chugoku District, western Honshu, Japan is described. The new species is assigned to Aegista Albers, 1850 based on its morphology and molecular phylogeny. Aegista hiroshifukudai n. sp. is phylogenetically distinct from all other closely related species and the shell has a relatively taller spire.http://zoobank.org/urn:lsid:zoobank.org:pub:B0D76861-D9E7-40DB-B1C4-D604D6090569

The role of natural selection in phenotypic evolution is central to evolutionary biology. Phenotypic evolution is affected by various factors other than adaptation, and recent focus has been placed on the effects of phylogenetic constraints and niche conservatism on phenotypic evolution. Here, we investigate the relationship between the shell morphology and habitat use of bradybaenid land snails of the genus Aegista and clarify the causes of the divergence in shell morphology among phylogenetically related species. The results of ancestral state reconstruction showed that arboreal species have evolved independently from ground-dwelling species at least four times. A significant association was found between shell shape and habitat use, despite the existence of a certain degree of phylogenetic constraint between these traits. A principal component analysis showed that arboreal species tend to have a relatively high-spired shell with a narrow umbilicus. By contrast, ground-dwelling species have a low-spired shell with a wide umbilicus. Although the latitude and elevation of the sampling locations showed no relationship with shell morphology, the geology of the sampling locations affected the shell size of arboreal species. The development of a well-balanced shell shape is one effective method for reducing the cost of locomotion under the force of gravity in each life habitat, resulting in the divergence in shell morphology and the independent evolution of morphologically similar species among different lineages. The present study suggests that ecological divergence is probably the cause of shell morphology divergence in land snails. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 114, 229–241.

Analyses of molecular phylogeny have revealed that phenotypically identified taxa do not reflect phylogenetic relationships. Such taxa often are not evolutionary significant and are misleading in describing and evaluating biological diversity. Herein, we investigated the molecular phylogeny of the East Asian bradybaenid land snail genera Aegista, Landouria, Trishoplita, and Pseudobuliminus to test whether morphology and current taxonomy reflect phylogenetic relationships. Our results document extensive parallel evolution and substantial incongruence between taxonomy and molecular phylogeny. Species with an elongated turret shell evolved independently five times, and hair-like ornamentation of the shell was independently gained or lost in a number of lineages. Although genital anatomy reveals phylogenetic conservatism to some extent, love dart and dart-related organs were lost independently at least three times in these genera. Accordingly, classification of these genera based on morphological traits did not reflect phylogenetic relationships, and, overall, these genera except for a few species should be tentatively assigned to a single genus as Aegista. The present findings suggest that radical revision is required for the taxonomy of bradybaenid land snails.

Aegista chejuensis and Aegista quelpartensis (Family-Bradybaenidae) are endemic to Korea, and are considered vulnerable due to declines in their population. The limited genetic resources for these species restricts the ability to prioritize conservation efforts. We sequenced the transcriptomes of these species using Illumina paired-end technology. Approximately 257 and 240 million reads were obtained and assembled into 198,531 and 230,497 unigenes for A. chejuensis and A. quelpartensis, respectively. The average and N50 unigene lengths were 735.4 and 1073 bp, respectively, for A. chejuensis, and 705.6 and 1001 bp, respectively, for A. quelpartensis. In total, 68,484 (34.5%) and 77,745 (33.73%) unigenes for A. chejuensis and A. quelpartensis, respectively, were annotated to databases. Gene Ontology terms were assigned to 23,778 (11.98%) and 26,396 (11.45) unigenes, for A. chejuensis and A. quelpartensis, respectively, while 5050 and 5838 unigenes were mapped to 117 and 124 pathways in the Kyoto Encyclopedia of Genes and Genomes database. In addition, we identified and annotated 9542 and 10,395 putative simple sequence repeats (SSRs) in unigenes from A. chejuensis and A. quelpartensis, respectively. We designed a list of PCR primers flanking the putative SSR regions. These microsatellites may be utilized for future phylogenetics and conservation initiatives.

Aegista aubryana is an endemic land snail in China. The complete mitochondrial genome of A. aubryana was first determined using long PCR reactions and primer walking method (accession number KT192071). The genome has a length of 14 238 bp, containing 37 typical mitochondrial genes (13 protein-coding genes, 22 tRNA genes and 2 rRNA genes). The base composition of the whole heavy strand is A 31.32%, T 37.86%, C 14.46% and G 16.36%. The results of phylogenetic analyses showed that the A. aubryana is most closely related to Mastigeulota kiangsinensis. This new complete mitochondrial genome can be the basic data for further studies on mitogenome comparison, molecular taxonomy and phylogenetic analyses in bradybaenid snails and Molluscs at large.

A paper by Tokubei Kuroda from 1953 is presented for the first time in English, with an introduction and annotation. It describes the main collecting expeditions commissioned by Yoichiro Hirase between 1900 and 1909. The localities and collection dates for the type material of the following species are given in more detail than in the original descriptions: Euhadra awaensis (Pilsbry, 1902); Trishoplita optima (Pilsbry, 1902); Mundiphaedusa kurozuensis (Pilsbry, 1902); Mundiphaedusa pachyspira (Pilsbry, 1902); Aegista (Coelorus) cavitectum (Pilsbry and Hirase, 1903); Karafthelix chishimana (Pilsbry and Hirase, 1904) [= K. blakeana (Newcomb, 1865)]; Mundiphaedusa hosoyaka (Pilsbry 1905); Luchuphaedusa azumai (Pilsbry, 1905); Luchuphaedusa ophidoon (Pilsbry, 1905).

Aegista subchinensis (Möllendorff, 1884) is a widely distributed land snail species with morphological variation and endemic to Taiwan. Three genetic markers (partial sequence of the mitochondrial cytochrome c oxidase subunit I [COI], the 16S rDNA and the nuclear internal transcribed spacer 2 [ITS2]) were analysed to infer phylogenetic relationships and genetic divergence of closely related species of the genus Aegista, Aegista vermis (Reeve, 1852) and Aegista oculus (Pfeiffer, 1850). A new species from Aegista subchinensis has been recognized on the basis of phylogenetic and morphological evidences. The nominal new species, Aegista diversifamilia sp. n. is distinguished from Aegista subchinensis (Möllendorff, 1884) by its larger shell size, aperture and apex angle; wider umbilicus and flatter shell shape. The northernmost distribution of Aegista diversifamilia sp. n. is limited by the Lanyang River, which is presumed to mark the geographic barrier between Aegista diversifamilia sp. n. and Aegista subchinensis.