Glyphidrilus huailuangensis Chanabun & Panha, 2013

Chanabun, Ratmanee, Sutcharit, Chirasak, Tongkerd, Piyoros & Panha, Somsak, 2013, The semi-aquatic freshwater earthworms of the genus Glyphidrilus Horst, 1889 from Thailand (Oligochaeta, Almidae) with re-descriptions of several species, ZooKeys 265, pp. 1-76 : 45-48

32. Glyphidrilus huailuangensis Chanabun & Panha sp. n. Figs 29 30 37 Table 1

Type material.

Holotype: CUMZ 3250 ( Fig. 30 ), in sandy loam near Huailung waterfall, Phujong-Nayoi National Park, Nachalauy, Ubon Ratchathani, Thailand, 14°26'31.8"N, 105°16'21.7"E, 393 m amsl, 25 April 2009. Paratypes: 2 adults and 6 juveniles (CUMZ 3251), and 1 adult (ZMH 14568), same collection data as holotype.

Etymology.

The name " huailuangensis " is given to this species for its type locality in the Huailung waterfall, Ubon Ratchathani. This is the first record of this genus at this locality.

Diagnosis.

Glyphidrilus huailuangensis sp. n. has unique characters of wi in 25, 26-30, 31, with clitellum in 12, 13, 16-32, 33; gm: lateral paired or asymmetrical on bc in 16-24, median paired on aa in 31; he in 8-11; sv in 9-12; ov in 13-14; testis in 10-11; sc absent ( Table 1 ).

Description of Holotype.

Dimensions: body length 91 mm, diameter 2.5 mm in segment 8, 1.9 mm before the clitellar wi in segment 25, 1.8 mm behind wi in segment 31 within the clitellar region. Body cylindrical in anterior part, quadrangular in transverse section behind clitellum. 228 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 26-30, 2.3 mm in height, and about 2.9 mm in width on both sides. Prostomium zygolobous. Dorsal pores absent. Clitellum annular in 12-32. Four pairs of setae per segment from 2, setal formula aa:ab:bc:cd:dd = 1.0:0.5:1.5:0.5:1.0 at 8 and 1.2:0.5:1.6:0.5:1.5 in postclitellar segments. Female pores, male pores, and spermathecal pores not visible. Gm: lateral paired or asymmetrical on bc in 16, 17-24, median paired on aa in 31.

Septa 5/6-8/9 thicker, 9/10-14/15 thick and 15/16 to the last segment thin. Gi within 7-8. Intestine enlarged from 13. Dorsal blood vessel aborted anterior to 8. He in 8-11. No distinguishable np in first twelve segments. Sv in 9-12, segment 12 larger than the others. Ov in 13-14. Testis in 10-11. Prostate and accessory glands and sc absent.

Variation.

Body lengths of adult paratypes (3) ranged from 50-91 mm (69 ± 20.7), with 131-228 segments. Clitellum in 12, 13, 16-32, 33. Wi in 25, 26-30, 31. Gm laterally paired or asymmetrical on bc in 16-24, median paired on aa in 31.

Distribution.

The new speciesis known only from the type locality. This species was found on the shore near water in sandy loam topsoil (80% sand, 13.1% silt, 5.6% clay, pH 7.5) and in the water at about 5-10 cm depth. The soil surface was covered with worm casts.

Remarks.

Glyphidrilus huailuangensis sp. n. similar to Glyphidrilus annandalei from India in the locations of wi however, Glyphidrilus annandalei has a bit longer wi in 25, 26, 27- ½32, 32, ½ 33, 33, 35, 36, with longer clitellum beginning in 13-18 and extending to 35-41 and sc in 13/14-16/17. The new species is similar to Glyphidrilus tuberosus from Borneo in the locations of wi and clitellum, however, Glyphidrilus tuberosus has median unpaired gm on aa in 12-14 and 29-31 and sc in 14-15. Differs from Glyphidrilus fluviatilis reported from River Harangi, Madapur by Glyphidrilus fluviatilis has larger body size, longer clitellum in 13-33, 36, 38, no gm on aa, he in 7-11, np from 16, and gi in 8. Differs from Glyphidrilus yunnanensis from China by the last has longer wi in 22-32, with a clitellum in 18-38. Differs from Glyphidrilus vangviengensis from Laos by the Glyphidrilus vangviengensis has longer wi in 24, 25-31, 32, and clitellum in 19, 20-35, 36, 37, 38, intestine in 15 and lacks sc.

The new species differs from Glyphidrilus chiensis sp. n. which has a larger size, with a bit longer wi in 23, 24, 25, 26-29, 30, 31, 32, and clitellum in 17, 18-33, 34, 35, 36, 37, 38 and sc in 12/13-18/19. It differs from Glyphidrilus quadratus sp. n. by Glyphidrilus quadratus sp. n. has larger size, with a bit longer wi in 23, 24-28, 29, 30, 31, and clitellum in 15, 16, 17, 18-31, 32, 33, 34, 35, 36 and sc in 12/13-17/18 ( Table 1 ).

Figures

Figure 29. Photographs showing the A and B type locality of Glyphidrilus huailuangensis sp. n. on sandy beach near Huailuang waterfall, Phujong-Nayoi National Park, Nachalauy, Ubon Ratchathani and C coloration of living paratype CUMZ 3251.

Figure 30. Morphology of the holotype (CUMZ 3250) of Glyphidrilus huailuangensis sp. n., showing the A external ventral and B internal dorsal views.

Figure 37. Distribution map of the new Glyphidrilus species from Thailand. Open triangle: Glyphidrilus borealis sp. n., Filled triangle: Glyphidrilus vangthongensis sp. n., Filled star: Glyphidrilus chaophraya sp. n., Open square: Glyphidrilus chiensis sp. n., Filled square: Glyphidrilus quadratus sp. n., Open circle: Glyphidrilus huailuangensis sp. n.