Glyphidrilus kratuensis Chanabun & Panha 2013

Dimensions: body length 83 mm, diameter 2.4 mm in segment 8, 2.9 mm before clitellar wi in segment 22, 2.8 mm behind wi in segment 30 in intraclitellar region. Body cylindrical in anterior part, quadrangular in transverse section behind clitellum. 235 segments. Body colour pale brown with variations from red to pink at adjacent tissues of wi portion in different individuals of newly collected specimens after placement in 30% ethanol for narcotization. Dorsal surface considerably broader than the ventral at posterior end. Clitellar wi on ventro-lateral part of clitellum in 23–28, 29, 2.4 mm in height, and about 0.6 mm in width on both sides. Prostomium zygolobous. Dorsal pores absent. Clitellum annular in 18–31. Four pairs of setae per segment start from 2, setal formula aa:ab:bc:cd:dd=1.0:0.6:1.7:0.7:1.1 in segment 8 and 0.9:0.4:0.8:0.4:1.0 in postclitellar segments. Female pores, male pores, and spermathecal pores are not visible. Gm: lateral paired or asymmetrical on bc in 15–16, 29, median paired on aa in 19–22 and 30–31. Septa 5/6–8/9 thicker, 9/10–11/12 thick and 12/13 to the last segment thin. Gi small globular within 8. Intestine enlarged from 14. Dorsal blood vessel aborted anterior to 8. He in 8–11. No distinguishable np in first twelve segments. Sv in 9–12. Ov in 13–14. Testis in 10–11. Prostate and accessory glands absent. Sc sessile, elongated oval or globular in 14/15–17/18, 0.4–0.5 mm in diameter, two on each side per segment.

Known from the type locality in Kratu waterfall, Kratu, Phuket in South Thailand. The new species was found on the shore connected to a waterfall in sandy mud topsoil covered with worm casts. Collections in nearby areas found other Glyphidrilus species but not this one.