Amynthas fluviatilis Zhao and Sun 2013, sp. nov.
Creators: name: Zhao, Qi
name: Sun, Jing
name: Jiang, Jibao
name: Qiu, Jiangping
Publisher: name: Zenodo
Year: 2013
Subjects: Biodiversity
Taxonomy
Animalia
Annelida
Clitellata
Opisthopora
Megascolecidae
Amynthas
Amynthas fluviatilis

description: <i>Amynthas fluviatilis</i> Zhao and Sun, sp. nov. (Figure 2) <i>Type material</i> Holotype: Clitellate specimen (C-HN014-01), 121 mm long, 3.2 mm wide, 119 segments. Setae numbers: 52/III, 56/ V, 40/ VIII, 46/XX, 55/XXV; 22(VI) between spermathecal pores, 5(XVIII) between male pores, collected in Jianfengling National Nature Reserve, south-west Hainan, (18 ◦ 43 ′ 58 ′′ N, 108 ◦ 53 ′ 10 ′′ E), at an altitude of 890 m. Collected by J. P. Qiu, M. Bouche, J. X. Li and W. X. Zhang. <i>Etymology</i> This species is named after its habitat near the river. <i>Diagnosis</i> Spermathecal pores two pairs, in 5/6–6/7, about 0.33 circumference apart. Small genital markings posterior to each pore. Male pores 0.33 circumference apart, ventrally placed, each on top of a tiny conical porophore, surrounded by five skin folds. A small papilla posterior to the left male pore. Another small papilla present in the middle of XVIII ventrally above setae line. <i>Description</i> Preserved specimens light brownish dorsally; no pigmentation before clitellum, but light brownish after clitellum ventrally. Dimensions 121 mm by 3.2 mm; segments 119. Setae sparsely paired, regularly distributed around segmental equators, their numbers: 52 at III, 56 at V, 40 at VIII, 46 at XX, 55 at XXV; 22(VI) between spermathecal pores, 5(XVIII) between male pores; setal formula AA = AB, ZZ = 1.3ZY. Female pore single in the ventral centre of XIV, ovoid, brown. First dorsal pore in 11/12. Prostomium 1/2 epilobous. Clitellum in XIV–XVI, ring-shaped, purplish, markedly glandular; setae invisible. Male pores paired in XVIII about 0.33 body circumference apart, ventrally placed, each on the centre of a slightly raised, tiny conical porophore, surrounded by five skin folds. A small papillae posterior to the left male pore. Another small papillae present in middle of XVIII ventrally above the setae line. Spermathecal pores two pairs in 5/6–6/7, ventral, eye-shaped, distance between them about 0.33 body circumferences apart. Two tiny genital markings posterior to each pore, but three tiny markings posterior to the left pore in 6/7. Septa 8/9, 9/10 absent; 6/7–7/8 comparatively thick and muscular; 10/11–12/13 thin but slightly thicker than those following. Gizzard barrel-shaped, in IX–X. Intestine starting enlarged in XV. Intestinal caeca simple, small, originating in XXVI, extending anterior to 1/2XXIV, dark brownish, with one slight incision on terminal dorsal margin, smooth ventrally. Oesophageal hearts four pairs, in X–XIII. Spermathecae two pairs, in VI–VII; ampulla ovoid, duct slender, a little shorter than ampulla, diverticulum short, as long as 0.25 of main pouch, ental 0.25 swollen, serving as seminal chamber, whitish in appearance. Testis-sacs paired in X and XI. Seminal vesicles paired in XI and XII, the first pair slender, the second more developed. Prostate gland in 1/2XVII–1/3XX, coarsely lobated, composed of some grey-brown vesicular capsule, its duct well-developed, U-shaped, and proximally appreciably enlarged. An accessory present in VII. <i>Remarks</i> <i>Amynthas fluviatilis</i> sp. nov. also keys to the <i>morrisi</i> -group according to Sims and Easton (1972). In appearance, <i>Amynthas fluviatilis</i> sp. nov. is somewhat similar to <i>Amynthas incongruus</i> (Chen, 1933). Both of them are moderate species with pigmentation. They have two pairs of spermathecal pores in 5/6–6/7, simple intestinal caeca, and no septa in 8/9–9/10. Furthermore, their spermathecae are similar. They have an ovoid ampulla with a duct a little shorter than the ampulla. Their diverticulum is small; there is an accessory gland around the prostate. But <i>Amynthas fluviatilis</i> sp. nov. has no accessory gland around the spermathecae, and its seminal vesicles are developed. A pair of small papillae is present in the middle of XVIII ventrally above the setae line in <i>Amynthas fluviatilis</i> sp. nov., which is similar to some individuals of <i>Amynthas incongruus</i>. However, there is only a small papilla posterior to the left male pore in <i>Amynthas fluviatilis</i> sp. nov. while three to seven small genital papillae occur around the male pores in <i>Amynthas incongruus</i>. In the spermathecal regions there are only two or three small genital markings posterior to each spermathecal pore in <i>Amynthas fluviatilis</i> sp. nov. while there are usually paired small genital markings pre- and/or post-setal in VI and/or VII in <i>Amynthas incongruus</i>. Occasionally, there are no genital markings in <i>Amynthas incongruus</i> (Table 3).
description: Published as part of <i>Zhao, Qi, Sun, Jing, Jiang, Jibao &amp; Qiu, Jiangping, 2013, Four new species of genus Amynthas (Oligochaeta, Megascolecidae) from Hainan Island, China, pp. 2175-2192 in Journal of Natural History (J. Nat. Hist.) (J. Nat. Hist.) 47 (33 - 34)</i> on pages 2183-2185, DOI: 10.1080/00222933.2013.775374, http://zenodo.org/record/5197518
description: {"references": ["Sims RW, Easton EJ. 1972. A numerical revision of the earthworm genus Pheretima auct. (Megascolecidae: Oligochaeta) with the recognition of new genera and an appendix on the earthworms collected by the Royal Society North Borneo Expedition. Biol J Linn Soc. 4: 169 - 268.", "Chen Y. 1933. A preliminary survey of earthworm of the Yangtze valley. Contri Biol Lab Sci Soc China (Zool Ser). 9: 178 - 296."]}