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Achaeta brevivasa Graefe, 1980 (Figures 9, 10) Achaeta brevivasa Graefe, 1980. Wang et al. 1999; Schmelz and Collado 2010. Material investigated GZO202007004–GZO202007005, stained and whole-mounted, two mature specimens from site H. CJJ 92– CJJ 94, three mature specimens from site 1, whole worm used for DNA extraction, preserved as total DNA. Further material investigated Two mature specimens from site H, two mature specimens from site I, one mature specimen from site A, two mature specimens from site 3, one mature specimen from site 8, one mature specimen from site 11: nine specimens in total, preserved in 75% ethanol. Description Small worm, 3.5–3.8 mm long, 0.15–0.18 mm wide at VII and 0.17–0.2 mm wide at clitellum. Number of segments (18) 20–26. Chaeta absent. Head pore on the tip of prostomium (Figure 9a). Body wall thin, thickness 8–15 mm, cuticle 1–2 mm (in vivo). No pyriform glands. Six lentiform epidermal gland cells per segment (Figure 10e). Clitellum saddled-shaped, hyalocytes in 6 baguette-like longitudinal rows in dorsal, conspicuous and depressed into the coelom, rectangle and closely packed, ca. 30–32 μm long and 9– 14 μm high, granulocytes inserted more or less regularly; granulocytes in dense transverse rows laterally, rectangle, ca. 20 μm long and 11 μm high (Figures 9a, 10h). Brain slightly convex posteriorly, ca. 1.5–2× as long as wide (154 μm long and 91 μm wide, in vivo) (Figures 9a, b, 10a). All three pairs of pharyngeal glands untied dorsally in IV/V–VI/VII, with ventral extension in V–VI, one pair of secondary pharyngeal gland lobes in VI (Figures 9a, 10b, c). One pair of spongy oesophageal appendages in V, small and inconspicuous (diameter ca. 30 μm, in vivo) (Figures 9a, 10b). Dorsal vessel originating from VII, blood colourless. Intestinal diverticula absent. Gut widening gradually in VII (Figures 9a, 10f). Chloragocytes yellowish-brown, sparse in IV–VII and dense from VII on. Nephridia two pairs in preclitellar segments, at 6/7 and 7/8 (Figures 9a, 10d). Nephridia constricted by septa, anteseptale with funnel and parts of nephridial body, ca. 39 μm long and 26 μm wide (in vivo); postseptale ca. 44 μm long and 27 μm wide (in vivo), with a ventral bump in mid-section, tapering gradually into efferent duct. Coelomocytes abundant and round, pale, ca. 9–13 μm in diameter. Seminal vesicle absent. Sperm funnel small, barrel-shaped, ca. 35–38 μm long, collar narrower than funnel body, 18–20 μm wide in collar and 21–27 μm wide in funnel body (in vivo) (Figures 9c, 10i). Spermatozoa short, 23–26 μm long, heads 10–13 μm long (in vivo) (Figures 9c, 10i). Sperm duct in coils, diameter ca. 4–4.5 μm (in vivo). Male copulatory organs small and inconspicuous. Spermathecae small, free, confined to V; ectal pores lateral at 4/5, without ectal glands; ectal ducts short, ca. 40 μm long and 11 μm wide (in vivo), the duct widening into narrow dilations of ampullar, ca. 25 μm long and 17 μm wide (in vivo) (Figures 9a, 10g). Only one mature egg (Figure 10h) at a time, with yellowishbrown granules, occupying 2–3 segments (Figure 9a). Remarks The morphological characters of our specimens correspond well with the original description (Graefe 1980); however, coelomocytes were without attached filaments in the redescription by Wang et al. (1999) based on specimens collected from Hunan Province and Hubei Province. This species has also been found in the Jilin, Gansu and Guizhou Provinces of China (Wang et al. 1999; J.J. Chen, unpublished data). Molecular results show that our specimens differ from Achaeta cf. brevivasa collected in Sweden (Erséus et al. 2010). Clear genetic gaps were observed between the two groups of specimens, with high interspecific distances (up to 18.7%) and low intraspecific distances (0%) based on the K2P distances of COI sequences. Achaeta brevivasa is a widespread morpho-species; it is probably a group of genetic species instead of only one, and the molecular differences are probably caused by weak dispersal capacity and long geographical distance., Published as part of Chen, Juanjuan, Schmelz, Rüdiger M., Zhang, Zuxu & Xie, Zhicai, 2022, The enchytraeid fauna (Enchytraeidae: Clitellata) of the Fanjing Mountain National Nature Reserve (China) with description of two new species, pp. 1957-1996 in Journal of Natural History 56 on pages 1973-1975, DOI: 10.1080/00222933.2022.2140085, http://zenodo.org/record/7426634, {"references":["Graefe U. 1980. Systematische Untersuchungen an der Gattung Achaeta (Enchytraeidae, Oligochaeta). 1. Beschreibung von Achaeta brevivasa sp. n. und Achaeta camerani (Cognetti). Mitteilungen aus dem hamburgischen zoologischen Museum und Institut. 77: 35 - 39.","Wang HZ, Xie ZC, Liang YL. 1999. Records of Enchytraeidae (Clitellata) from the People's Republic of China. Hydrobiologia. 406: 57 - 66. doi: 10.1023 / A: 1003732116567.","Schmelz RM, Collado R. 2010. A guide to European terrestrial and freshwater species of Enchytraeidae (Oligochaeta). Soil Org. 82: 1 - 176.","Erseus C, Rota E, Matamoros L, Wit PD. 2010. Molecular phylogeny of Enchytraeidae (Annelida, Clitellata). Mol Phylogenet Evol. 57 (2): 849 - 858. doi: 10.1016 / j. ympev. 2010.07.005."]}

Achaeta cf. brevivasa Graefe, 1980 (Figure 13, A,B) NIBRIV0000320532, NIBRIV0000320533, slides 1084, 1085. Two adult fixed and stained specimens, collected from site 11. Segment number 20���23, length 3.1���3.5 mm, in vivo, 2.1���2.7 mm long and about 200���210 ��m wide, fixed. Pyriform glands absent, lentiform epidermal glands not detected. Clitellum and male openings in XII. Clitellum with 6 baguette-rows of hyalocytes; between rows, at the edges, granulocytes present (Fig. 13 B). Brain 65���75 ��m long (fixed) and about 1.5 times longer than wide, rounded posteriorly. Coelomocytes rounded, about 44 ��m long. One pair small secondary pharyngeal glands in VI, not well visible. Two pairs preclitellar nephridia in 6 / 7, 7/ 8. Sperm funnels small, 40���50 ��m long and 20���21 ��m wide. Spermathecae in V, about 65���75 ��m long in vivo (Fig. 13 A). The whole mounts are unfortunately not of good quality; secondary pharyngeal glands could not be seen with certainty, and lentiform epidermal glands were not detected, either. For these reasons we added a "cf." to the species name., Published as part of D��zsa-Farkas, Kl��ra, Felf��ldi, Tam��s & Hong, Yong, 2015, New enchytraeid species (Enchytraeidae, Oligochaeta) from Korea, pp. 171-197 in Zootaxa 4006 (1) on page 191, DOI: 10.11646/zootaxa.4006.1.9, http://zenodo.org/record/237087