Glyphidrilus satunensis Chanabun & Panha

Chanabun, Ratmanee, Inkavilay, Khamla & Panha, Somsak, 2017, New species of semi-aquatic freshwater earthworm genus Glyphidrilus Horst, 1889 from Thailand and Laos (Oligochaeta, Almidae), ZooKeys 672, pp. 1-34 : 4-6

Glyphidrilus satunensis Chanabun & Panha sp. n. Figs 2, 5, Table 1

Material examined.

Holotype: One adult (CUMZ 3405), in Nong Prakpraya, Mueang, Satun, Thailand (06°44'34.0"N, 100°02'23.0"E), 27 meters elevation on 16 January 2014. Paratypes: 15 adults and 21 juveniles (CUMZ 3406), 2 adults (ZMH 14580), 2 adults (NHMUK), and 2 adults (ZRC), all same collection data as holotype.

Diagnosis.

Glyphidrilus satunensis sp. n. has the clitellar wings on the lateral side of the body in XXIV, XXV, XXVI–XXIX, XXX, XXXI. Clitellum in XVII, XVIII–XXXII, XXXIII, XXXIV, XXXV. Female pores, male pores and spermathecal pores not visible. Genital markings: unpaired on aa in XVI, XVII, XVIII–XXII, XXIII, XXIV; paired or asymmetrical on bc in XVII, XVIII, XIX. Four pairs of seminal vesicles in IX–XII. Intestinal origin in XVI. Ovaries in XIII–XIV. Spermathecae between 13/14-15/16.

Description of holotype.

Dimensions: body length 131 mm, diameter 2.2 mm in segment VIII, 2.3 mm before the clitellar wing in segment XXIII, 2.4 mm after wing in segment XXX in clitellar region; body cylindrical in anterior part, quadrangular in transverse section behind clitellum. 326 segments. Body color pale brown with variations from red to pink at adjacent tissues of wing portion in different individuals of newly collected specimens. At posterior end dorsal surface considerably broader than the ventral. Clitellar wing on ventro-lateral part of clitellum in XXIV–XXIX, 2.5 mm in height, and 0.5 mm in width on both sides. Prostomium zygolobous. Dorsal pores absent. Clitellum annular in XVII–XXXIII. Four pairs of setae per segment from II, setal formula aa:ab:bc:cd:dd = 1.0:0.5:1.5:1.0:1.5 in segment VIII and 1.0:0.5:1.5:0.5:2.0 in postclitellar segments. Female pores, male pores, and spermathecal pores not visible. Genital markings: unpaired on aa in XVII–XXII.

Septa 5/6-7/8 thicker than between other segments, 8/9-9/10 thick and 10/11 to the last segment thin. Gizzard small, globular in VII. Intestine enlarged from XVI. Hearts, four pairs in VIII–XI. A pair of holonephridia in each segment from segment XIII onwards. Seminal vesicles, four pairs in IX–XII. Ovaries, two pairs in XIII–XIV. Testes free in X and XI. Prostate and accessory glands absent. Spermathecae sessile and diverticula absent, elongated oval or globular between 13/14-15/16, about 0.2-0.3 mm in diameter, four to five on each side per segment.

Variations.

Body lengths of adult (n = 22) and juvenile paratypes (n = 21). Adults ranged from 60+-131 mm (95.8 ± 24.5), with 156+-326 segments. Juveniles ranged from 62-129 mm (82.5 ± 22.1), with 166-323 segments. Wings in XXIV, XXV, XXVI–XXIX, XXX, XXXI, clitellum in XVII, XVIII–XXXII, XXXIII, XXXIV, XXXV. Genital markings: unpaired on aa in XVI, XVII, XVIII–XXII, XXIII, XXIV; paired or asymmetrical on bc in XVII, XVIII, XIX.

Distribution.

The new species was found at a pond in Satun, south Thailand.

Etymology.

The name " satunensis " is given in reference to the type locality, Satun.

Remarks.

See Table 1 for a summary of these comparisons. Glyphidrilus satunensis sp. n. is quite similar to G. kratuensis Chanabun & Panha, 2013 from Kratu waterfall, Kratu, Phuket, south Thailand in the location of wings but G. kratuensis has a smaller size, a shorter clitellum in XVIII–XXX, XXXI, XXXII, the intestine begins from XIV, and spermathecae are between 14/15-17/18. It differs from G. trangensis Chanabun & Panha, 2013 from Trang River, Nayong, Trang, south Thailand by the latter having wings in XXII, XXIII–XXVII, XXVIII, the clitellum in XVII, XVIII–XXX, and spermathecae in XVIII–XXI. It differs from G. wararamensis Chanabun & Panha, 2013 from stream near Wattham Wararam, Phanom, Suratthani, south Thailand by G. wararamensis having wings in XX, XXI–XXVI, XXVII, a clitellum in XI, XII, XIII–XXXIII, XXXIV, XXXV, and spermathecae between 13/14-17/18. It differs from G. nanensis sp. n. by G. nanensis having a smaller size, slightly shorter wings in XXIV, XXV, XXVI–XXVII, XXVIII, XXIX, unpaired genital markings absent, five pairs of hearts in VII–XI, and spermathecae between 13/14-17/18 (see Table 1).