Amynthas carnosus ( Goto & Hatai, 1899 )

Chang, Chih-Han, Snyder, Bruce A. & Szlavecz, Katalin, 2016, Asian pheretimoid earthworms in North America north of Mexico: An illustrated key to the genera Amynthas, Metaphire, Pithemera, and Polypheretima (Clitellata: Megascolecidae), Zootaxa 4179 (3), pp. 495-529 : 505

2. Amynthas carnosus ( Goto & Hatai, 1899)

( Figure 8 )

Perichaeta carnosa Goto & Haitai, 1899: 15 .

Pheretima carnosa — Kobayashi 1936: 115.

Amynthas carnosus — Sims & Easton 1972: 235. Blakemore 2012a: 36; 2013b: 58; 2013c: 101. Carrera-Martínez & Snyder 2016: 297 .

Amynthas pingi (Stephenson, 1925) — Sims & Easton 1972: 235. Blakemore 2013c: 112.

Data sources. Blakemore (2012a, 2013b, c); Carrera-Martínez & Snyder (2016).

Diagnosis. Size 110–340 mm by 4–9 mm. Segment numbers 106–179. Color of live specimens dark brown or purple. Male pores paired in XVIII, simple, on round or elliptical porophores. Post-clitellar genital markings paired, pre-setal on XVIII and XIX, mid-ventral or widely spaced; post-setal on XVIII, slightly median to male pores; markings variously lacking or completely absent. Spermathecal pores four pairs in 5/6/7/8/9 or three pairs in 6/7/8/9. Pre-clitellar genital markings paired on VIII and IX, pre-setal, mid-ventral or widely spaced, variously lacking. Female pore single in XIV. First dorsal pore 12/13. Spermathecae four pairs in VI–IX or three pairs in VII– IX, ampulla oval or pear-shaped, duct equal to or slightly shorter than ampulla, diverticulum reaching one-third to half of ampulla with a slender stalk and a wider seminal chamber. Prostate glands well-developed, extending through XVII–XIX. Intestinal caeca paired in XXVII, simple, extending anteriorly to XXIII or XXIV.

Remarks. This species is newly recorded in North America in 2015 near Manhattan in Kansas (Carrera- Martínez & Snyder 2016), and therefore has never been included in any previous US pheretimoid earthworm keys ( Reynolds 1978; Gates 1982). Amynthas carnosus has only been recorded from Japan, Korea and China, and a previous report from Taiwan has been confirmed to belong to a different species ( Blakemore 2012a; 2013c). Reproduction of A. carnosus is presumably amphimictic.

Figures

FIGURE 8. Amynthas carnosus. (A) Right male pore region and the associated genital markings (arrows). (B) Pre-clitellar genital markings paired mid-ventral on VIII and IX and eight spermathecal pores right behind eight genital markings (arrows). (C) Right spermathecae in VII – IX. Only the spermathecal diverticulum in IX is visible. (D) Right spermatheca in IX. (E) Right prostate gland and its duct (arrow). (F) Right intestinal caecum.