Glyphidrilus borealis Chanabun & Panha 2013

Dimensions: body length 67 mm, diameter 2.5 mm in segment 8, 1.9 mm before the clitellar wi in segment 21, 1.8 mm after wi in segment 29 in clitellar region; body cylindrical in anterior part, quadrangular in transverse section-behind clitellum. 247 segments. Body colour pale brown with variations from red to pink at adjacent tissues of wi portion in different individuals of newly collected specimens. At posterior end dorsal surface considerably broader than the ventral. Clitellar wi on ventro-lateral part of clitellum in 22–28, 3.1 mm in height, and 0.6 mm in width on both sides. Prostomium zygolobous. Dorsal pores absent. Clitellum annular in 17–33. Four pairs of setae per segment from 2, setal formula aa:ab:bc:cd:dd = 1.5:0.8:1.8:0.8:1.7 in segment 8 and 1.7:0.8:1.9:0.5:2.0 in postclitellar segments. Female pores, male pores, and spermathecal pores not visible. Gm laterally paired or asymmetrical on bc in 17–22, and 29. Septa 5/6–8/9 thicker, 9/10–14/15 thick and 15/16 to the last segment thin. Gi small, globular within 7–8. Intestine enlarged from 13. Dorsal blood vessel anterior to 7. He in 7–11. A pair of np bladder in each segment from segment 14 onwards. Sv in 9–12. Ov in 13–14. Testis in 10–11. Prostate and accessory glands absent. Sc sessile, elongated oval or globular in 14/15–18/19, about 0.2–0.3 mm in diameter, two to twelve on each side per segment.

The new species was found on the canal connected to waterfall in sandy loam topsoil (70% sand, 26% silt, 4% clay, pH 7.1–7.5) covered with the worm casts in the north of Thailand at middle to higher elevations (388–677 m amsl).