Amynthas bouatongi, Hong & Inkhavilay & James, 2018

Hong, Yong, Inkhavilay, Khamla & James, Samuel W., 2018, Nine new species of the " aeruginosus " - group in Amynthas (Clitellata: Megascolecidae) from Nam Et-Phouley National protected Area, Laos, Zootaxa 4496 (1), pp. 238-250 : 239-241

Amynthas bouatongi sp. nov.

( Figure 1A,B )

Material. Holotype: clitellate ( BDNUL0031 ): Laos, Hoaphane Province , Nam Et-Phouleoi NPA, Viengthong district, Hoauy Kanang Mountain, 1075m asl, 20o15.572'N, 103o09-629'E, good forest condition in dark soil, 22 July 2005, Phimphet, Xay, Ammaline, Phoang sone, and K. Inkhavilay colls . Paratype: 1 clitellate ( BDNUL0032 ), same data as for holotype . Other material: 7 aclitellates, same data as for holotype .

Etymology. The species is named for Mr. Bouatong, one of the local people assisting the team.

Diagnosis. Spermathecal pores paired in 7/8, 8/9 at 10th–11th setal lines; Male pores superficial in XVIII at 9th setal lines at center of elongate reniform pad, 0.20–0.28 circumference apart ventrally; paired genital papillae medial and lateral to male pores in XVIII.

Description. Dimensions 70–75 mm, by 3.6–4.1 mm at segment X, 3.5–4.0 mm at segment XXX, 3.8–4.0 mm at clitellum; body cylindrical, segments 79–99. Setae slightly set closer ventrally, numbering 54–56 at VII, 47–50 at XX, 5–10 between male pores, setal formula AA:AB:ZZ:YZ= 2:1:3:2 at XIII. Female pore single in XIV, on an oval porophore. Prostomium epilobic with tongue open, light red-brown to brown in pre-clitellar segments, clitellum coffee color; formalin preservation. First dorsal pore at 5/6. Clitellum annular XIV–XVI; setae invisible externally. Male pores superficial in XVIII at 9th setal lines at center of elongate reniform pad, 0.20–0.28 circumference apart ventrally. Two pairs of equatorial genital papillae in XVIII, one lateral and the other medial to male porophores; each papilla with a small central pore. Spermathecal pores two pairs in 7/8–8/9 at 10th–11th setal lines, 0.23–0.28 circumference apart ventrally; pores lip-like, edge whitened and wrinkled.

Septa 5/6/7 thick, 7/8 thin, 8/9, 9/10 absent, 10/11–12/13 very thin. Gizzard large in VIII–X. Intestine enlarged from XV, lymph glands not found. Typhlosole small fold from XXVII. Intestinal caeca originating in XXVII and extending anteriorly about to XXIII, simple elongate finger-shaped. Hearts esophageal X–XIII. Male sexual system holandric, testes and funnels in ventrally joined sacs in X, XI. Seminal vesicles paired in XI, XII with very small round dorsal lobes. Prostates in XVIII, extending from XVII–XX; both glandular portions divided into 9–11 small lobes, ducts long, muscular, coiled. Genital papilla glands not found. Ovaries in XIII. Spermathecae paired in VII or VIII, IX; ampulla irregular-shaped, flattened by gizzard, very short duct, seminal chamber pointed egg-shaped with small black spots on surface, stalk slightly bent, shorter than ampulla, no nephridia on spermathecal ducts. Genital marking glands not found.

Remarks. Amynthas bouatongi sp. nov., the following eight new species, and Amynthas choanus ( Thai & Samphon, 1988) , Amynthas uanus (Thai & Samphon, 1990) , and Amynthas otoforme s ( Thai & Samphon, 1989) which have spermathecal pores on 7/8, 8/9, all have simple intestinal caeca, and dorsal pores either from 5/6 or from 11/12+/-. Those with dorsal pores in or near 5/6 also have long muscular prostatic ducts, which in many species are coiled in a clockwise spiral on the left side and an anti-clockwise spiral on the right side. Collective differences of all these species from A. aeruginosus are the lack of MV genital papillae in post-clitellar segments, lack of paired pre- and post-setal genital papillae in XVIII medial to male pores, lack of lymph glands on the dorsal intestine, and caeca shorter than 8 segments ( Sims & Easton 1972; based on A. aeruginosus including two synonymized species which they suggest might be sub-specifically distinct).

The new species is similar to A. phadeangensis Hong, 2010 from Nam Xam NPA. Amynthas phadeangensis has male pores in XVIII at the 6th setal lines in small invaginations partly covered by raised U-shaped flap concave medially, but A. bouatongi sp. nov. has male pores superficial on reniform porophores in XVIII at the 9th setal lines. Also A. phadeangensis has fewer setae than A. bouatongi sp. nov. (38–39, 40–42 vs. 46–52 on VII, 45–52 on XX).

Amynthas bouatongi sp. nov. shares some internal characteristics of the septa, spermathecae, intestine, caeca type, hearts, and esophageal hearts with A. naphopensis Hong, 2010 . But A. naphopensis has an unusual intestine, which is deeply pouched in XXI–XXV. Amynthas bouatongi sp. nov. has smaller number of setae between the male pores than A. naphopensis (5–10 vs. 29–42), and smaller spermathecal pore spacing (0.23–0.25 vs. 0.27– 0.34). Amynthas bouatongi sp. nov. differs from A. longisiphonus ( Qiu, 1988) from Guizhou, China, by the shape of the male pore region and genital markings. A. longisiphonus has 5–8 pairs of genital papillae in XVIII–XXII or XXV, but Amynthas bouatongi sp. nov. has only two pairs in XVIII. The new species also is quite different from A. robustus ( Perrier, 1872) and A. arrobustus Thai, 1984 with respect to the shape of male pore region, and numbers and distribution of genital papillae and genital markings.

Figures

FIGURE 1. Amynthas bouatongi sp. nov. (A,B), Amynthas hoauykanangensis sp. nov. (C,D), and Amynthas phimpheti sp. nov. (E,F). A,C,E: ventral view; B,D,F: spermatheca. Scale bars 2 mm.