This study reviews the Dicharax species in Thailand. Altogether ten Dicharax species are reported, four of which are new to science and described herein. They are Dicharax borealis Jirapatrasilp & Páll-Gergely sp. nov., Dicharax burchi Jirapatrasilp & Páll-Gergely sp. nov., Dicharax panhai Jirapatrasilp & Páll-Gergely sp. nov. and Dicharax pongrati Jirapatrasilp & Tongkerd sp. nov.Alycaeus davisi Godwin-Austen, 1914 is regarded as a junior subjective synonym of Alycaeus cucullatus Theobald, 1870 (= D. cucullatus) based on a similar depressed-conical shell shape, a long sutural tube and a sharp swelling behind the peristome. Furthermore, the type locality of Alycaeus pratatensis Panha & Burch, 1997 (= D. pratatensis) had to be amended. Most important characters to distinguish Dicharax species are the general shell shape and relative lengths of teleoconch regions, whereas the spiral striation of R1, the shape of swelling of R3, the outer peristome crenulation and protrusion, and the exterior opercular sculpture show large intraspecific variability.

中文翻译：

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在泰国经营的微型蜗牛属Dicharax Kobelt＆Möllendorff，1900年（Caenogastropoda，Alycaeidae），并描述了新物种

这项研究回顾了泰国的狄加拉克斯物种。总共报告了十种双夏char属物种，其中四个是科学新知识，在此进行了描述。他们是Dicharax borealis Jirapatrasilp和Páll-Gergelysp。十一月，Dicharax burchi Jirapatrasilp和Páll-Gergelysp。十一月，Dicharax panhai Jirapatrasilp＆Páll-Gergelysp。十一月 和Dicharax pongrati Jirapatrasilp＆Tongkerd sp。nov.Alycaeus davisi Godwin-Austen，1914被认为是Alycaeus cucullatus Theobald，1870（= D. cucullatus）的初级主观同义词，其基于类似的圆锥形凹陷的贝壳形状，细长的缝合管和在骨膜后面的急剧肿胀。此外，必须修改Alycaeus pratatensis Panha＆Burch，1997（= D. pratatensis）的类型局部性。