Amynthas wiggeri, 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 : 244-246

Amynthas wiggeri sp. nov.

( Figure 2E,F )

Material. Holotype: clitellate ( BDNUL0044 ): Laos, Hoaphane Province , Nam Et-Phouley NPA, Viengthong district, slope of Phouley Mountain, 2071m (20o16.612'N, 103o11.582'E), wet mossy forest, very thick surface layer; 23 July 2005, Boutong, Phimphet, Son and K. Inkhavilay coll. 2 paratypes: 2 clitellates ( BDNUL0045 , BDNUL0046 ), same data as for holotype. Other material: 1 clitellate , same data as for holotype.

Etymology. The species is named for the late Al Wigger, a California educator and fan of earthworms, at the request of his friends.

Diagnosis. Male pores near lateral margins of ventrum in XVIII at 12th setal lines, 0.22–0.30 circumference apart ventrally, at center of arc-shaped pad composed of two reniform sections joined end-to-end, arc convex laterally. Paired genital papillae equatorial on XVIII, just medial to male pores; paired papillae equatorial in XVII, XIX; spermathecal pores two pairs in 7/8–8/9 at 11th setal lines; first dorsal pore 4/5 or 5/6; stout prostatic ducts one complete loop clockwise (L), anti clockwise (R).

Description. Dimensions 140–153 mm, by 5.4–5.8 mm at segment X, 4.7–5.0 mm at segment XXX, 5.0– 5.1 mm at clitellum; body slightly flattened ventrally, segments 111. Setae more crowded ventrally numbering 59–64 at VII, 73–75 at XX, 12–15 between male pores, setal formula AA:AB:ZZ:YZ= 2:1:3:3 at XIII. Female pore single in XIV, on a circular porophore 0.3–0.4 mm in diameter. Prostomium epilobic with tongue open, clitellum light brown, anterior dorsum purple-brown, post-clitellum setal rings lighter, formalin preservation. First dorsal pore at 5/6 (3 individuals) and 4/5 (1 individual); from xx, ladder-like ventrum over ventral-most 24 setal intervals, these setae very closely spaced (0.13 mm); appearance due to elevated segmental equators. Clitellum annular XIV–XVI; setae invisible externally. Male pores near lateral margins of ventrum in XVIII at 12th setal line, 0.22–0.30 circumference apart ventrally, at center of arc-shaped pad composed of two reniform sections joined end-to-end, arc convex laterally. Paired genital papillae equatorial on XVIII, just medial to male pores; paired papillae equatorial in XVII, XIX just lateral to male pores. Spermathecal pores paired in 7/8/9 at 11th setal line, deep in furrows, near lateral margins of ventrum, 0.21–0.25 circumference apart ventrally. Genital markings lacking in preclitellar segments.

Septa 5/6 thick, 6/7 thicker, 7/8 thickest, 8/9/10 absent, 10/11 thick, 11/12/13 thinly muscular. Gizzard large in VIII–X. Intestine enlarged from XVI, lymph glands not found. Typhlosole small from XXVII. Intestinal caeca originating in XXVII extending anteriorly about to XXIV, simple finger-shaped. Hearts esophageal X–XIII; IX lateral, right side not developed. Male sexual system holandric, testes and funnels in large ventrally joined sacs in X, XI. Seminal vesicles paired, well-developed in XI, XII; with small round dorsal lobes. Prostates in XVIII, extending from XVII–XIX; stout ducts one complete coil clockwise (L), anti clockwise (R); glandular portions consisted of 3 main lobes. Genital papilla glands not found. Ovaries in XIII. Spermathecae two pairs in VII, VIII; ampulla cordate, flattened, grooves on surfaces, muscular ducts shorter than ampulla, iridescent seminal chamber bean-shaped, with thin coiled stalk; coils bound together, shorter than ampulla; stalk joins duct near ampulla base, no nephridia on ducts.

Remarks. This species is in the Laotian aeruginosus -group section characterized by long prostatic ducts often in mirror-image coils, first dorsal pore in 5/6 or nearby, and lack of pre-clitellar genital markings. Among the species reported here, in Hong (2010), and by Thai and Samphon (1989), it is closest to those with reniform genital papillae associated with the male pores. Those species are A. somechanae sp. nov. and A. bouatongi sp. nov. Amynthas wiggeri sp. nov. has on each side two such papillae joined end-to-end to form an arc whose convex side faces laterally. Each of the other two species has only one reniform papilla per side. Amynthas wiggeri sp. nov. is also larger and has more setae per segment than the other two species, and has a more posterior intestinal origin.

Figures

FIGURE 2. Amynthas nametensis sp. nov. (A,B), Amynthas somechanae sp. nov. (C,D), and Amynthas wiggeri sp. nov. (E,F). A,C,E: ventral view; B,D,F: spermatheca. Scale bars 2 mm.