Rhiostoma Ngocthachi

''Rhiostoma'' is a genus of operculate land snails in the subfamily Cyclophorinae of the family Cyclophoridae, native to parts of Asia.MolluscaBase eds. (2021). MolluscaBase. Rhiostoma Benson, 1860. Accessed through: World Register of Marine Species at: http://www.marinespecies.org/aphia.php?p=taxdetails&id=886689 on 2021-06-05

They are sometimes referred to as "snorkel snails" due to the tubular structure found on the final whorl of their shell, which resembles a snorkel.

Description

The shell is subdiscoidal with a broad umbilicus. The last whorl is separate from the rest of the shell and features a tube-like snorkel structure. The operculum is multispiral.

Etymology

The name is derived from "rhion" meaning a promontory and "stoma" meaning hole. In anatomy, a promontory is another word for a protuberance, so ''Rhiostoma'' can be understood to mean "protruding hole." This name refers to the snorkel on the shell which is the defining characteristic of the genus.

Ecology

Somwang Pathamakanthin of Thailand said about the ecology of ''Rhiostoma'', "As we have kept some living animals of ''Rhiostoma'' species in our garden, we know that most of them burrow into the ground during the day and are active only when it is raining or-sometimes-during the night, when the temperature is lower and the humidity is higher. When it is extremely hot during the day, we observed that species of the large variety of ''Rhiostoma smithi'' (from the Chanthaburi province) preferred to move into water, where they stayed for days! Others have been resting under the shade of trees, under rocks and fallen wood. We have been informed that the bluish Rhiostoma from Songkhla province prefers to burrow into the soil underneath fallen wood or under stones close to the foot of limestone hills.""

Taxonomy

Species within the genus ''Rhiostoma'' include MolluscaBase (2018). Rhiostoma Benson, 1860. Accessed at: http://molluscabase.org/aphia.php?p=taxdetails&id=886689 on 2019-09-15
* '' Rhiostoma abletti'' Thach, 2016 (taxon inquirendum, debated synonym)
* † '' Rhiostoma americanum'' G. D. Hanna, 1920
* '' Rhiostoma asiphon'' Möllendorff, 1893
* '' Rhiostoma battambangense'' Thach & F. Huber, 2020
* ''Rhiostoma boxalli'' Godwin-Austen, 1893
* '' Rhiostoma cambodjense'' Morelet, 1875
* '' Rhiostoma chupingense'' Tomlin, 1938
* '' Rhiostoma dalyi'' Blanford, 1902
* '' Rhiostoma grohi'' Thach, 2020
* '' Rhiostoma hainesi'' Pfeiffer, 1862
* '' Rhiostoma haughtoni'' Benson, 1860
* '' Rhiostoma herosae'' Thach & F. Huber, 2017
* '' Rhiostoma housei'' (Haines, 1855)
* '' Rhiostoma huberi'' Thach, 2018
* ''Rhiostoma jalorense'' Sykes, 1903
* '' Rhiostoma jousseaumei'' de Morgan, 1885
* '' Rhiostoma macalpinewoodsi'' Laidlaw, 1939
* '' Rhiostoma marioni'' (Ancey, 1898)
* '' Rhiostoma morleti'' Dautzenberg & H. Fischer, 1906
* '' Rhiostoma ngocngai'' Thach & F. Huber, 2018
* '' Rhiostoma ngocthachi'' F. Huber, 2020
* ''Rhiostoma ninhbien'' D. S. Do, T. S. Nguyen & H. L. Do, 2020
* ''Rhiostoma samuiense''
* ''Rhiostoma simplicilabre'' L. Pfeiffer, 1862
* ''Rhiostoma smithi'' Bartsch, 1932
* ''Rhiostoma strubelli'' Möllendorff, 1899
* ''Rhiostoma thachi'' F. Huber, 2018
* ''Rhiostoma thorsengi'' Thach, 2020
* ''Rhiostoma tomlini'' Salisbury, 1949
;* Species brought into synonymy:
* ''Rhiostoma americana'' G. D. Hanna, 1920 †: synonym of ''Rhiostoma americanum'' G. D. Hanna, 1920 † (wrong gender agreement of specific epithet)
* ''Rhiostoma battambangensis'' Thach & F. Huber, 2020: synonym of R''hiostoma battambangense'' Thach & F. Huber, 2020 (wrong gender agreement of specific epithet)
* ''Rhiostoma bernardii'' L. Pfeiffer, 1862: synonym of '' Opisthoporus bernardii'' (L. Pfeiffer, 1862) (original combination)
* ''Rhiostoma cavernae'' Godwin-Austen, 1889: synonym of '' Opisthoporus cavernae'' (Godwin-Austen, 1889) (original combination)
* ''Rhiostoma gwendolenae'' Godwin-Austen, 1889: synonym of '' Cyclotus gwendolenae'' (Godwin-Austen, 1889) (original combination)
* ''Rhiostoma hungerfordi'' Godwin-Austen, 1889: synonym of '' Cyclotus hungerfordi'' (Godwin-Austen, 1889) (original combination)
* ''Rhiostoma iris'' Godwin-Austen, 1889: synonym of '' Cyclotus iris'' (Godwin-Austen, 1889) (original combination)
* ''Rhiostoma macalpine-woodsi'' Laidlaw, 1939: synonym of ''Rhiostoma macalpinewoodsi'' Laidlaw, 1939 (hyphens are not accepted in specific epithet)
* ''Rhiostoma ninhbinhensis'' Thach & F. Huber, 2018: synonym of ''Rhiostoma ninhbinhense'' Thach & F. Huber, 2018 (wrong gender agreement of specific epithet)
* ''Rhiostoma spelaeotes'' Tomlin, 1931: synonym of '' Pterocyclos spelaeotes'' (Tomlin, 1931) (original combination)
;Taxa inquirenda:
* ''Rhiostoma abletti'' Thach, 2016 (debated synonym)
* ''Rhiostoma christae'' Thach, 2016 (debated synonym)
* ''Rhiostoma ngocngai'' Thach & F. Huber, 2018 (debated synonym)
* ''Rhiostoma ninhbinhense'' Thach & F. Huber, 2018 (debated synonym

References

External links

Kobelt W. (1902). Das Tierreich. Eine Zusammenstellung und Kennzeichnung der rezenten Tierformen. 16. Lieferung. Mollusca. Cyclophoridae. Das Tierreich. XXXIX + 662 pp., 1 map.

Cyclophoridae
Gastropod genera

{{Cyclophoridae-stub