An undescribed pipe snake from Thailand (JCM) and a map
showing the known taxa.
In a new paper Amarasinghe et al. (2015) examine the systematics of the genus and redefine based only uon specimens from Java Cylindrophis ruffus, they C. burmanus using the type series collected from Myanmar, and designate a lectotype. They identified four groups based on the number of scale rows around the midbody (17, 19, 21, and 23). Among the Cylindrophis examined they discovered two new species: C. jodiae sp. nov. from Vietnam and C. mirzae sp. nov. from Singapore. This paper is a good start on revising the genus but it leaves many undescribed species in places like Sumatra. Borneo, and most of the Indochinese peninsula.
Amarasinghe AAT, Campbell PD, Hallermann J, Sidik I, Supriatna J, Ineich I. 2015. Two new species of the genus Cylindrophis Wagler, 1828 (Squamata: Cylindrophiidae) from Southeast Asia. Amphibian & Reptile Conservation 9(1): 34–51 (e98).