Amynthas lilis Shen, 2025

Amynthas lilis Shen sp. nov.

urn:lsid:zoobank.org:act:89141457-A609-429E-9BF5-4054AE69066A

Fig. 5 View Fig

Amynthas corticis View in CoL – James et al. 2005: 1023 (partim).

Diagnosis

Length (clitellates) 70–85 mm. Segments numbering 74–98. Setae 36–51 in VII, 50–57 in XX, 12–13 between male pores. First dorsal pore in 11/12 or 13/14. Clitellum XIV–XVI. Spermathecal pores four pairs in 5/6–8/9, 0.28–0.30 body circumference ventrally apart. Male pores 0.27–0.31 body circumference ventrally apart in XVIII. Genital papillae small, mid-ventral, 0–5 presetal papillae in a row and 0–3 postsetal papillae in a row on each segment of VII–IX and XVII–XX. Spermathecae four pairs in VI–IX. Seminal vesicles large, two pairs in XI and XII, each occupying 1.5–2 segments. Prostate glands lobed, occupying 3–4 segments in XVI–XX. Prostatic ducts C-shaped in XVIII. Accessory glands stalked.

Etymology

The species is named after the nearby Lili Creek in Chunrih, Pingtung County, Taiwan.

Type material

Holotype

TAIWAN • clitellate (mature) specimen; Nanhe, Chunrih , Pingtung County; 22°26′33″ N, 120°39′03″ E; 133 m a.s.l.; 19 Aug. 1999; Chung-Chi Hwang and Jin-Kuan Yang leg.; NMNS-8595-003. GoogleMaps

Paratypes

TAIWAN • 5 clitellates; same data as for holotype; NMNS 4054-034 View Materials GoogleMaps .

Description

Length (mature) 70–85 mm. Number of segments 74–98. Setae regularly distributed around segmental equators, size and distance regular, numbering 36–51 in VII, 50–57 in XX, 13–14 between spermathecal pores, 12–13 between male pores in XVIII. Prostomium epilobous. First dorsal pore in 11/12 or 13/14. Clitellum XIV–XVI, smooth, setae and dorsal pores absent, length 2.7–3.3 mm and width 4.1–5.7 mm. Spermathecal pores four pairs in 5/6–8/9, paired pores 0.28–0.30 body circumference ventrally apart. Genital papillae small, mid-ventral in VII–IX, number highly variable. In VII, 0–3 presetal papillae in a row and 0–2 postsetal papillae in a row; in VIII, 1–5 presetal papillae in a row and 0–2 postsetal papillae in a row; in IX, 0–3 presetal papillae in a row and 0–3 postsetal papillae in a row; an additional presetal papilla in VI for holotype ( Fig. 5A View Fig ). Each papilla about 0.3 mm in diameter. Female pore single, mid-ventral in XIV.

Male pores paired, ventro-lateral in XVIII, paired pores 0.27–0.31 body circumference ventrally apart, each porophore surrounded by one or two shallow circular folds. Genital papillae small, mid-ventral, often in XVII–XX, number and arrangement highly variable. In XVII, 0–3 presetal papillae in a row and 0–2 postsetal papillae in a row; in XVIII, 0–3 presetal papillae in a row and 0–2 postsetal papillae in a row; in XIX, 0–3 presetal papillae in a row and 0 or 1 postsetal papilla; in XX, 0–3 presetal papillae in a row and 0 or 1 postsetal papilla; additional papillae present in XXI–XXV and XXVII–XXVIII for holotype ( Fig. 5B View Fig ). Each papilla 0.3–0.4 mm in diameter. Preserved specimens brown and dark brown on clitellum.

Septa 5/6–7/8 thickened, 8/9/10 absent, 10/11–13/14 thickened. Nephridial tufts on anterior faces of 5/6/7. Gizzard in VIII–X. Intestine enlarged from XV. Intestinal caeca paired in XXVII, simple, bent, extending anteriorly to XXII or XXI. Esophageal hearts paired in XI–XIII.

Spermathecae four pairs in VI–IX. Ampulla peach- or elongated oval-shaped, surface wrinkled, 0.9– 2.1 mm in length and 0.8–1.6 mm in width, with a short, stout stalk 0.3–0.5 mm long. Diverticulum with a large, round or oval, iridescent seminal chamber 0.5–1.1 mm in length and a slender stalk 0.5–0.9 mm in length ( Fig. 5C View Fig ). Accessory glands stalked, 0.4–0.6 mm in total length, each corresponding to external genital papilla. In addition, one or two stalked glands near each spermathecal pore, 0.4–0.6 mm in total length. Ovaries paired in XIII.

Holandric. Testes oval, two pairs in ventrally joined sacs in X and XI. Seminal vesicles large, two pairs in XI and XII, each vesicle occupying 1.5–2 segments, each with a large, round dorsal lobe. Prostate glands paired in XVI–XIX, XVII–XIX or XVII–XX, lobed, wrinkled. Prostatic ducts C-shaped in XVIII, distal end enlarged ( Fig. 5D View Fig ). Accessory glands stalked, 0.6–0.8 mm in total length, each corresponding to external genital papilla.

Distribution

Known only from type locality (Chunrih, Pingtung County, Taiwan).

Remarks

The character of a longitudinal series of genital papillae on the mid-ventral line in A. lilis sp. nov. sets it apart from A. corticis . This papilla arrangement is akin to that of A. catenus Tsai, Shen & Tsai, 2001 from elevations of 2200–3000 m, central Taiwan ( Tsai et al. 2001; Shen et al. 2019). However, A. catenus is a parthenogen with spermathecae from absence to three pairs in VI–VIII, small, vestigial seminal vesicles, and prostate glands from absence to large in XVI–XX ( Tsai et al. 2001). No sperm was found and spermatozoal iridescence was not observed in any of the spermathecae examined for A. catenus ( Shen et al. 2011, 2012).