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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. Journal of Natural History 56: 1957-1996, DOI: 10.1080/00222933.2022.2140085, URL: http://dx.doi.org/10.1080/00222933.2022.2140085

Hemienchytraeus cf. stephensoni Cognetti, 1927 (Figure 18) Hemienchytraeus stephensoni Cognetti, 1927. See Schmelz and Collado (2007) for list of synonymies, and for nomenclatural and taxonomic history of the nominal species. Material investigated GZO202007006, stained and whole-mounted, terminal segments absent, one mature specimen from site H; GZO202007007, stained and whole-mounted, one submature specimen from site H. CJJ 135, one mature specimen from site I, whole worm used for DNA extraction, preserved as total DNA. Further material investigated One mature specimen from site H, two mature specimens and one immature specimen from site I, six mature specimens from site 1, one mature specimen from site C and one mature specimen from site E, 12 in total, preserved in 75% ethanol. Description Small to medium-sized worms. Length 5.8–9.2 mm, diameter 0.21–0.34 mm at VII, 0.29– 0.35 mm at clitellum. Number of segments 32–38. Chaetae faintly sigmoid, anterior chaetae ca. 32.5–40 μm long and 3.75–5 μm thick, terminal chaetae enlarged (about 1.5× as large as anterior), ca. 52.5–62.5 μm long and 5–7.5 μm thick (Figure 18c). Body wall 25.1–29.7 μm thick, cuticle very thin. Epidermal gland cells inconspicuous, cells nearly rectangular, 4–6 transverse rows per segment and arranged in regular order. Clitellum in XII–1/2XIII, girdle-shaped, well developed, granulocytes dense and arranged in reticulate with hyalocytes, hyalocytes isolated from each other, midventrally almost exclusively granulocytes (Figure 18h). Head pore on prostomium mid-dorsally. Brain nearly rectangular, incised anteriorly and slightly concave posteriorly, about 232 μm long and 153 μm wide (in vivo) (Figure 18a). Oesophageal appendages arising mid-dorsally behind the pharynx in III, one root with large proximal chamber, two primary branches longer than root, with smaller branches; each primary branch bifurcating into three secondary branches, secondary branches thinner and shorter than primary branches (Figure 18b). Three pairs of pharyngeal glands in IV–VI, united in IV–V and separated in VI dorsally, two pairs of secondary ventral lobes in V and VI, almost equal size. Dorsal vessel from XII to XIV, blood colourless. Four pairs of preclitellar nephridia from 6/7 to 9/10, anteseptale consisting of funnel and parts of nephridial body, ca. 43 μm long and 36 μm wide (in vivo); narrowed at septum, postseptale ca. 94 μm long and 59 μm wide (in vivo). Efferent duct originating from the middle of postseptale (Figure 18d). Coelomocytes elliptic, brown in transmitted light, diameter 30– 33 μm (in vivo) (Figure 18i). Seminal vesicle absent. Sperm funnel tapering distad, collar indistinct, wider than funnel body, ca. 282–356 μm long and 50–57 μm wide at collar (in vivo) (Figure 18f, g, i). Spermatozoa sparse, about 125 μm long (in vivo). Sperm duct elongate, with few coils in XIII. Male copulatory organ (Figure 18h) small, male glandular body globular, diameter ca. 60 μm (in vivo). Spermathecae (Figure 18e) free, not attached to oesophagus. Ectal pores at 4/5, no ectal gland. Ectal ducts muscular, short, ca. 61 μm long and 9 μm wide (in vivo); ampullae wider than ectal ducts (36 μm long, 14 μm wide, in vivo). Connecting tubes thinner than ampullae (337 μm long, 11 μm wide, in vivo), extending into VII, ending in ellipsoid ental reservoirs (70 μm long, 20 μm wide, in vivo). Ental reservoirs thin-walled, empty or with spermatozoa. Remarks Hemienchytraeus stephensoni was recorded in China by Xie et al. (1999), but the specimens were considered misidentified by the original authors, in a subsequent, detailed taxonomic revision of the species (Schmelz and Collado 2007). The key characters (such as body size, chaetae, oesophageal appendage and spermatheca) of our specimens conform well to the description of H. stephensoni (Schmelz and Collado 2007)., 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 1987-1989, DOI: 10.1080/00222933.2022.2140085, http://zenodo.org/record/7426634, {"references":["Cognetti ML. 1927. Lumbricidi dei Carpazi. Bolllettino dei Musei di Zoologia e Anatomia comparata della Reale Universita di Genova. 2 a (7): 1 - 8.","Schmelz RM, Collado R. 2007. Revision of Hemienchytraeus stephensoni (Cognetti, 1927) (Enchytraeidae, Oligochaeta, Annelida). Folia Facultatis scientiarum naturalium Universitatis Masarykianae Brunensis, Biologia. 110: 67 - 85."]}

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."]}

Hemienchytraeus tenuiculus sp. nov. (Figures 6–8) Holotype Fully mature, whole-mounted specimen, stained, GZO202007012. Type locality Site 2. Soil and moss layer of Cyclobalanopsis glauca forest (108°42′58.7″E, 27°54′28.91″N), 2000 m asl, Fanjing Mountain, Guizhou, China, coll. Z.X. Zhang, Y.H. Ge and J.J. Chen, 25 December 2019. Paratypes GZO202007013, GZO20201010001, stained and whole-mounted, two mature specimens from the type locality, same data as holotype. CJJ81, CJJ125, CJJ126, CJJ130, four mature specimens from site 2, CJJ 82, one mature specimen from site 4, CJJ 83, one mature specimen from site I, CJJ 132, one mature specimen from site 8: seven specimens in total, whole worm used for DNA extraction, preserved as total DNA. Further material investigated One mature specimen from site 6, one mature specimen from site 10 and one mature specimen from site 12: three specimens in total, preserved in 75% ethanol. Etymology Named for the small and thin body. Diagnosis The species can be diagnosed by the following combination of characters: (1) worms small and thin; (2) each primary branch bifurcating into two secondary branches; (3) spermathecae extending to VII–VIII; (4) no secondary pharyngeal glands; (5) three pairs of preclitellar nephridia in 6/7–8/9; (6) dorsal vessel originating from postclitellar segments; (7) clitellum girdle-shaped. Description Small worms, transparent. Length 3.4–7.3 mm, diameter 0.12–0.21 mm at VII and 0.14– 0.23 mm at clitellum. Number of segments 30–43. Chaetae straight without inner hook, with slight proximal bend. Two chaetae per bundle throughout, absent in XII in mature worms (Figure 6a). Ventral chaetae in anterior region ca. 25–37.5 μm long and 5 μm thick, chaetae in caudal region somewhat increasing in size, ca. 30–50 μm long and 5–6.5 μm thick. Lateral chaetae almost of equal size throughout, ca. 25–30 μm long and 5 μm thick. Head pore on prostomium mid-dorsally (Figure 6a). Body wall 18–23 μm thick (in vivo), cuticle thin. Epidermal gland cells inconspicuous, 3–4 rows per segment, nearly rectangular, parallel or at chaetal level (Figure 7c). Clitellum in XII–1/2XIII, scarcely thickening, girdle-shaped, hyalocytes and granulocytes in dense transverse rows (Figures 6a, 7i). Brain ca 1.5× as long as wide (95 μm long, 65 μm wide, in vivo), deeply concave anteriorly, weakly incised posteriorly (Figures 6a, 7a). Oesophageal appendage with unpaired root dorsally behind pharyngeal pad in III, root with large lumen, extending posteriad, bifurcating into two primary branches, with meandering canal; each primary branch bifurcating further into two longer and thinner secondary branches, with smaller canal (Figures 6a, b, 7b, e). Three pairs of pharyngeal glands, poorly developed, pharyngeal glands in IV united dorsally, small, without ventral lobes, in V and VI dorsally separate, with ventral lobes (Figures 6a, 7f). No secondary pharyngeal gland lobes. Dorsal vessel beginning behind clitellum (segment XIV), blood colourless. Three pairs of preclitellar nephridia from 6/7 to 8/9 (Figure 6a), each about 115 μm long and 42 μm wide (in vivo). Anteseptale globular, consisting of funnel and parts of nephridial body, with coils of canal, postseptale elongate, length ratio of anteseptale: postseptale ca 1:1.3. Efferent duct originating from the middle of postseptale. Coelomocytes elongate, elliptical, numerous, 34–42 μm long, 15–18 μm wide (in vivo) (Figure 7g). Seminal vesicle absent. Sperm funnel cylindrical, tapering distally, ca. 106 μm long and 36 μm wide at collar (in vivo). Collar indistinct, as wide as funnel body, canal conspicuous (Figures 6c, 7g). Spermatozoa sparse, short, ca. 150 μm long, head ca. 18 μm long (in vivo) (Figures 6c, 7g). Diameter of sperm ducts ca. 6 μm, long and coiling unregularly in XII (Figure 7h). Male copulatory organs muscular, male glandular body oval, ca. 55 μm long and 23 μm wide (Figure 6a). Spermathecae free, not attached to oesophagus. Ectal pores lateral at 4/5, without ectal glands. Ectal ducts muscular, short, ca. 54 μm long and 10 μm wide (in vivo), with distinct ampullar dilatations in V (ca. 12 μm in diameter, in vivo); ampullar connecting tubes thinner than ectal ducts (ca. 8 μm wide, in vivo), extending into VII or VIII, ending in ellipsoid ental reservoirs, ca. 92 μm long and 19 μm wide (in vivo), ental reservoirs thin-walled, with spermatozoa (Figures 6a, 7d). One mature egg at a time. Remarks Among Hemienchutraeus species, there are six members with the same bifurcate branching pattern of the oesphageal appendage: H. bifurcatus Nielsen and Christensen, 1959, H. csuzdii Dózsa-Farkas, 1989, H. jeonjuensis Dózsa-Farkas and Hong, 2010, H. planisetosus Xie et al., 1999, H. solimoensis Righi, 1978 and H. tanjae Schmelz et al., 2005. Among them, the new species is most similar to H. jeonjuensis in possessing three pairs of preclitellar nephridia from 6/7 to 8/9, spermathecae extending to VII–VIII, a girdle-shaped clitellum and the absence of a seminal vesicle. However, in H. jeonjuensis, there are two pairs of secondary pharyngeal glands in V and VI, respectively, and the dorsal vessel originates in preclitellar segments (X–XI). The new species resembles H. csuzdii in the absence of secondary pharyngeal glands and a seminal vesicle, and in the postclitellar origination of the dorsal vessel. Conspicuous morphological differences from H. csuzdii include a short spermatheca confined to V and the first pair of preclitellar nephridia in 5/6. Hemienchytraeus planisetosus, H. solimoensis and H. tanjae differ from the new species in their longer spermathecae, presence of secondary pharyngeal glands, and the number and position of preclitellar nephridia. The comparison of the new species with H. bifurcatus is difficult due to the lack of several key morphological traits in the original description of the latter; for example, nothing is known about the pharyngeal glands and the preclitellar nephridia. Schmelz et al. (2005) considered H. bifurcatus to be a species inquirenda since its type material is lost. Repeated attempts to collect specimens at the type locality have so far not been successful (Schmelz, unpublished data). However, it is unlikely that H. tenuiculus sp. nov. and H. bifurcatus are the same species: the segments are fewer in the latter, despite some overlap with the former (28–32), and its clitellum is said to be ‘strongly elevated’ (Nielsen and Christensen 1959), while it is flat in the new species. Another difference can be inferred from the original illustration of H. bifurcatus (Nielsen and Christensen 1959, fig. 27), which shows a brain with length:width ratio of 1:1. Furthermore, H. bifurcatus has been recorded only in Europe [Denmark, Germany and Poland (Schmelz and Collado 2010)]. Hemienchytraeus tenuiculus sp. nov. is also clearly different from two species included in the DNA sequence comparison (Figure 8), H. koreanus Dózsa-Farkas and Hong, 2010 and H. wuhanensis Chen et al., 2021. In both species each primary branch of the oesophageal appendage divides into more than two secondary branches. Furthermore, the two species have three pairs of secondary pharyngeal glands and five pairs of preclitellar nephridia, from 5/6 to 9/10. It is noteworthy that the morphological similarity of the new species and H. jeonjuensis is not reflected in the DNA sequences (Figure 8). Phylogenetic analysis of the concatenated sequences (COI, H3 and ITS) shows that H. tenuiculus sp. nov. is monophyletic with respect to the other three species of Hemienchytraeus included in the analysis (Figure 8). However, the clade of the new species includes three branches, which suggests cryptic diversity within this morphospecies. For a detailed analysis see below (in the section on Molecular species delimitation).

Fridericia cf. loretensis Schmelz, 2003 (Figures 13, 14) Fridericia callosa (Eisén, 1872). Černosvitov 1937. Fridericia loretensis Schmelz, 2003. Material investigated GZO202106001–GZO202106002, stained and whole-mounted, two mature specimens from site 7, GZO202106003 stained and whole-mounted, one mature specimen from site 11. CJJ 99– CJJ 100, two mature specimens from site 7, CJJ 123– CJJ 124, two mature specimens from site 11, whole worm used for DNA extraction, preserved as total DNA. Description Small worms, white in stereomicroscope. Length 6.3–7.6 mm, diameter 0.22– 0.34 mm at VII, 0.23–0.4 mm at clitellum. Number of segments 36–46. Chaetae straight, without inner hook, formula 2–4 – 2–3: 4–6 – 2–5. A maximum of 6 per bundle, mostly 5 in ventral preclitellar bundles, the number of chaetae lower towards posterior body end (Figure 14d). Body wall 23–48 μm, cuticle thin. Epidermal gland cells 2–3 rows per segment, one at chaetal level, distinct, rectangular; the other two rows closely before or behind, cells few and scattered (Figure 14g). Brain elongated egg-shaped, anterior margin convex, posterior margin rounded, ca. twice as long as wide (153: 81 μm, in vivo) (Figures 13b, 14a). A pair of oesophageal appendages (Figure 13a) arising from ventral pharynx, free at IV/V, with short primary branches. Three pairs pharyngeal glands in IV – VI, in IV with wide dorsal connection and without ventral lobes; in V and VI dorsally separate and with ventral lobes, those in VI larger than those in V (Figures 13a, 14c). Five pairs preclitellar nephridia from 6/7–10/11, details not seen. Dorsal vessel from XVI–XVII, blood colourless. Coelomocytes two types, mucocytes numerous, with fine granulation and regular outline, diameter ca. 35 μm (in vivo); lenticytes small, millet-shaped. Chylus cells in XIII–XV, occupied about two segments. Clitellum girdle-shaped, well developed, gland cells in dense transverse rows, gland cells much taller (ca. 12.5–20 μm) than wide (ca. 3.8–7.5 μm); granulocytes rectangular, hyalocytes isolated from each other (Figure 14h, i). Seminal vesicle absent or very small. Head of spermatozoa ca. 83 μm (in vivo) (Figures 13c, 14e, f). Sperm funnel cylindrical, 164 μm long and 58 μm wide (funnel body) (in vivo), collar distinct, slightly narrower than funnel body, canal inconspicuous (Figures 13c, 14e, f). Vas deferens long and thin, diameter ca. 10 μm (in vivo), coiled irregularly in XIII. Glandular bulb of male copulatory organ hemispherical, ca. 73 μm long and 38 μm wide, with distinct musculature (Figure 14h). Bursal slit staple-shaped. No subneural glands . Spermathecae. Ectal pores laterally at 4/5, no ectal gland; ectal ducts ca. 12 μm wide and 171 μm long (in vivo), projecting proximally slightly into ampullae, projection nearly as wide as ectal duct. Ampullae without diverticula, distal part globular, diameter ca. 35 μm, thin-walled, sperm in a circle around projected ectal duct endpiece, proximal part cylindrical, 45 μm long and 16 μm wide, lumen small; proximal part of ampullae elongate, forming ental ducts, short, separate opening dorsally into oesophagus (Figures 13a, 14b). Remarks The original description of F. loretensis is based on preserved material from Argentina, first identified as F. callosa (Eisén) (Černosvitov 1937; Schmelz 2003). This is the first record of F. loretensis in China, and the first record of the species after the original description. Our specimens correspond well to the original description, but there are a number of slight differences, difficult to evaluate: smaller body size (length: 6.3–7.6 mm vs 10–11 mm, number of segment: 36–46 vs 51–54), fewer chylus cells (occupying 2 segments vs 3 ½ or 4 segments) and smaller glandular bulb (length: 73 μm vs 150–155 μm). Furthermore, dimensions in vivo and the texture of coleomocytes is unknown in F. loretensis. Due to these uncertainties, our identification remains tentative. In China, this species is also distributed in Guangxi, Yunnan, Jiangsu and Guizhou Provinces (J.J. Chen, unpublished data)., 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 1979-1982, DOI: 10.1080/00222933.2022.2140085, http://zenodo.org/record/7426634, {"references":["Schmelz RM. 2003. Taxonomy of Fridericia (Oligochaeta, Enchytraeidae). Revision of species with morphological and biochemical methods. Abhandlungen des Naturwissenschaftlichen Vereins in Hamburg, Neue Folge. 38: 1 - 415.","Eisen G. 1872. Om nagra arktiska Oligochaeter. - Ofv. Kongl. Vetenskaps-Akad Forh. 1: 119 - 124.","Cernosvitov L. 1937. Notes sur les Oligochaeta (NaIdidees et Enchytraeidees) de l'Argentine. Ann Mus Argent. 39: 135 - 157."]}

Fridericia sp. (Figures 15, 16) Material investigated GZO202010002, stained and whole-mounted, one mature specimen from site 1, GZO202010003, stained and whole-mounted, one mature specimen from site 7. CJJ 101, CJJ 122, two mature specimens from site 1, whole worm used for DNA extraction, preserved as total DNA. Further material investigated Five mature specimens from site 1, one mature specimen from site 7, one mature specimen from site 12, seven specimens in total, preserved in 75% ethanol. Description Small worms. Length 6–7 mm. Diameter 0.2–0.25 mm at VII, 0.24–0.3 mm at XII. Number of segments 39–46. Chaetae straight, without pronounced ental hook (a small bend is present), formula 2–4 – 2, 3: 3, 4 – 2–4. A maximum of 4 per bundle, mostly 4 in ventral preclitellar bundles, inner pair slightly thinner and shorter than outer pair, mostly 2 in posterior body half. Epidermal gland cells elongate, scattered in 3–4 rows per preclitellar segment, 4–5 cells in first row, followed by a second row with more cells. Body wall ca. 15 μm in thickness (in vivo). Clitellum girdle-shaped, cells arrangement almost reticulate, hyalocytes distinctly larger than granulocytes. Brain ovoid, anteriorly convex, posteriorly rounded. A pair of short, unbranched oesophageal appendages free in ventral part of IV–V (Figure 15a). Pharyngeal glands with dorsal connection present in IV, absent in V and VI. Ventral lobes absent in IV, largest in VI (Figures 15a, 16a). Four pairs of preclitellar nephridia, from 6/7–9/10, anteseptale ca. half as long as postseptale, medial origin of efferent duct. Coelomocytes. Mucocytes with refractile vesicles at the cell periphery, lenticytes milletshaped, scarce. Dorsal vesicle from XVIII, blood colourless. Chylus cells in XIII–XIV, occupying 2 segments (Figure 16d). Seminal vesicle absent. Sperm funnel cylindrical, tapering proximad, collar distinct, somewhat narrower than funnel body, ca. 143 μm long, 41 μm (at collar) and 53 μm (at funnel body) wide (in vivo) (Figures 15d, e, 16e, f). Spermatozoa ca. 150 μm (in vivo). Male copulatory organ medium-size, bursal slit staple-shaped. Subneural glands absent. Spermathecae without ectal gland; ectal ducts elongate (ca. 230 μm, in vivo), slightly projected into ampullae;ampullae without diverticula,onion-like, lumen large, containing sperm; proximal part elongate, forming ental ducts, adjacent or joint opening of the spermathecae into oesophagus dorsally (Figures 15b, c, 16b, c). Remarks The investigated specimens agree in almost all characters with Fridericia bretscheri Southern, 1907, especially when considering the redescriptions by Rota (1995) and Schmelz (2003). However, the absence of spermathecal ectal glands disagrees with the diagnosis of Fridericia bretscheri, where the gland is conspicuously large, its size being one of the key characters of the species. Furthermore, in our specimens postclitellar segments have predominantly 2 chaetae per bundle, while in F. bretscheri there are 4 or 3. The colour of epidermal gland cells and pattern of midventral clitellar gland cells are unknown in our specimens. Before erecting this species as new and different from F. bretscheri, we prefer to wait for more specimens from the Mt. Fanjing site to complete the description and for DNA sequences from European populations of F. bretscheri., 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 1982-1985, DOI: 10.1080/00222933.2022.2140085, http://zenodo.org/record/7426634, {"references":["Southern R. 1907. Oligochaeta of Lambay. Irish Nat J Dublin. 16: 68 - 82.","Rota E. 1995. Italian Enchytraeidae (Oligochaeta). I. Ital J Zool. 62: 183 - 231. doi: 10.1080 / 11250009509356067","Schmelz RM. 2003. Taxonomy of Fridericia (Oligochaeta, Enchytraeidae). Revision of species with morphological and biochemical methods. Abhandlungen des Naturwissenschaftlichen Vereins in Hamburg, Neue Folge. 38: 1 - 415."]}

Henlea perpusilla Friend, 1911 (Figure 17) Henlea perpusilla Friend, 1911. Černosvitov 1937; Nielsen and Christensen 1959; Chalupský 1986; Kasprzak 1986; Rota and Healy 1994; Rota 1995; Rota et al. 1998; Wang et al. 1999; Schmelz and Collado 2010; Lu et al. 2018. Henlea brucei Stephenson, 1922. Henlea balcanica Černosvitov, 1930. Material investigated GZO202007008–GZO202007009, stained and whole-mounted, two mature specimens from site H. CJJ 87, one mature specimen from site 1, whole worm used for DNA extraction, preserved as total DNA. Further material investigated Six mature specimens and one immature specimen from site H, one mature specimen from site B, seven mature specimens from site 1, two mature specimens from site 7 and one mature specimen from site 12, 18 in total, preserved in 75% ethanol. Description Small worms. Length 5.7–10.4 mm (in vivo), diameter 0.32–0.43 mm at VII, 0.35–0.5 mm at clitellum (in vivo). Number of segments 26–39. Chaetae without inner hook, straight distally, slightly bent proximally, fan-shaped, short in the middle and long on the side. Chaetae formula 3–6 – (2)3–5: 4–6 (7,8) – 3–6. Body wall 12.5–25 μm thick, cuticle very thin (Epidermal gland cells rectangular, 2–3 rows per segment (Figure 17c). Clitellum at XII–1/2XIII, girdle-shaped, developed well, thickened both dorsally and ventrally, gland cells reticulate, hyalocytes in contact with each other (Figure 17h). Brain flat anteriorly and weakly concave posteriorly, ca. 130 μm long, 107 μm wide (in vivo) (Figure 17a). Pharyngeal glands 3 pairs in IV–VI, all separate dorsally (Figure 17d). Preclitellar nephridia 5 pairs, 6/7–10/11. Gut abruptly widened at 7/8, no intestine diverticulum (Figure 17e). Dorsal vessel rising in VIII, pulsating and conspicuous, blood pale (Figure 17e). Coelomocytes only mucocytes, finely and regularly vesicular, diameter 40–47 μm (in vivo). Chloragocytes yellowish, forming a thin layer on the intestine from VII. Seminal vesicle absent. Sperm funnel cylindrical, small, collar distinct, nearly as wide as funnel body. Length and width varies among specimens, 49–108 μm long, 35–50 μm wide (in vivo), ca 1.4–2.1 × as long as wide (Figure 17g, i). Vas deferens long, coiled irregular, diameter 6.5 μm (in vivo). Spermathecae without ectal gland. Ectal pores lateral at 4/5; ectal ducts muscular, short, 55.3 μm long, 24.5 μm wide; ampullae spindle-shaped, thiner than ectal ducts, 110.9 μm long, 18.6 μm wide (in vivo); ental ducts narrower than ampullae, united before attachment to oesophagus in V (Figure 17b). 1–2 mature eggs at a time, occupying 1–3 segments (Figure 17f). Remarks This species is common and widespread around the world. In China, the worms have been found in Hunan, Jilin, Gansu, Yunnan, Xinjiang, Guizhou Provinces and Tibet (J.J. Chen, unpublished data). K2P distances were calculated based on COI sequences: high genetic distances were shown between our species and H. perpusilla from Sweden (Erséus et al. 2010) (18.2%), H. perpusilla from Svalbard (Dózsa-Farkas et al. 2015) (16.0%) and H. perpusilla from Switzerland (Vivien et al. 2015) (18.2%). Henlea perpusilla is probably a species complex, containing several species., 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 1985-1987, DOI: 10.1080/00222933.2022.2140085, http://zenodo.org/record/7426634, {"references":["Friend H. 1911. New British Henleas. Zool Ser. 4 (15): 464 - 468.","Cernosvitov L. 1937. Notes sur les Oligochaeta (NaIdidees et Enchytraeidees) de l'Argentine. Ann Mus Argent. 39: 135 - 157.","Nielsen CO, Christensen B. 1959. The Enchytraeidae. Critical revision and taxonomy of European species (Studies on Enchytraeidae VII). Natura Jutlandica 8 - 9: 1 - 160.","Chalupsky J. 1986. Czechoslovak enchytraeids (Oligochaeta, Enchytraeidae) I. Enchytraeids from an apple orchard by Bavorov in South Bohemia. Vestnik Ceskoslovenske spolecnosti zoologicke. 50: 13 - 21.","Kasprzak K. 1986. Skaposzczety wodne i glebowe, II. Rodzina: wazonkowce (Enchytraeidae). Polska Akademia Nauk Instytut Zoologii, Warszawa. 366.","Rota E, Healy B. 1994. The enchytraeid fauna of North Africa. Hydrobiologia. 278 (1 - 3): 53 - 66. doi: 10. 1007 / BF 00142311.","Rota E. 1995. Italian Enchytraeidae (Oligochaeta). I. Ital J Zool. 62: 183 - 231. doi: 10.1080 / 11250009509356067","Rota E, Healy B, Erseus C. 1998. Biogeography and taxonomy of terrestrial Enchytraeidae (Oligochaeta) in Northern Sweden, with comparative remarks on the genus Henlea. Zool Anz. 237: 155 - 169.","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.","Lu YJ, Xie ZC, Zhang JQ. 2018. Preliminary taxonomical investigation of soil enchytraeids (Clitellata, Enchytraeidae) from south region of Tibet, China. Zootaxa. 4496 (1): 395 - 410. doi: 10.11646 / zoo taxa. 4496.1.29.","Stephenson J (1922) The Oligochaeta of the Oxford University Spitsbergen expedition. Proceedings of the Zoological Society of London, 74, 1109 - 1138. 10.1111 / j. 1469 - 7998.1922. tb 07096. x","Cernosvitov L. 1930. Zur Kenntnis der Oligochatenfauna des Balkans. I. Uber die Oligochaten aus Bosnien. Zool Anz. 86: 319 - 333.","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.","Dozsa-Farkas K, Felfoldi T, Hong Y. 2015. New enchytraeid species (Enchytraeidae, Oligochaeta) from Korea. Zootaxa. 4006 (1): 171 - 197. doi: 10.11646 / zootaxa. 4006.1.9.","Vivien E, Wyler S, Lafont M, Pawlowski J. 2015. Molecular barcoding of aquatic oligochaetes implications for biomonitoring. PLoS ONE. 10 (4): 1 - 15. https: // journals. plos. org / plosone / article / file? id = 10.1371 / journal. pone. 0125485 & type = printable"]}

Xetadrilus prolixglandus sp. nov. (Figures 2–5) Holotype Fully mature, whole-mounted specimen, stained, GZO202007003. Type locality Site I. Soil and moss layer of Cyclobalanopsis glauca, Pinus taiwanensis and Eurya japonica mixed forest (108°39′ 24.79°E, 27°54′ 43.15°N), 1970 m asl, Fanjing Mountain, Guizhou, China, coll. Z.X. Zhang, X.K. Jiang and J.J. Chen, 25 July 2019. Paratypes GZO202007001, GZO202007002, stained and whole-mounted, two mature specimens from the type locality, same data as holotype. GZO202008001, GZO202008002, stained and whole-mounted, two mature specimens from site F. CJJ91, one mature specimen from site 1, whole worm used for DNA extraction, preserved as total DNA. Further material investigated One mature specimen from site C, nine mature specimens from site F, one mature specimen from site G, two specimens from site H, four specimens from site I; three mature specimens from site 1, three mature specimens from site 2, one mature specimen from site 3, one specimen from site 4, one specimen from site 5, one specimen from site 9, two specimens from site 10: 29 specimens in total, preserved in 75% ethanol. Etymology The Latin prefix ‘prolix-’ means extended and elongate; ‘prolixglandus’ refers to the elongation of the third pair of pharyngeal glands, consisting of an anterior dorsal part in VI and a posterior ventral part in VI–VII. Diagnosis This new species can be diagnosed by the following combination of traits: (1) ventral chaetae in posterior segments enlarged, ca. 1.5× as large as anterior; (2) the third pair of pharyngeal glands elongate, with separate dorsal lobes in VI; (3) two pairs of secondary pharyngeal gland lobes in V–VI; (4) brown coelomocytes with refractile vesicles completely filled; (5) spermathecae free, confined to V; (6) epidermal gland cells distributed evenly; (7) gut widening gradually in VII, no intestinal diverticula; (8) two pairs of preclitellar nephridia in 7/8–8/9; (9) dorsal vessel originating from XII–XIII, blood colourless. Description Small-sized worms. Length 2.4–3.5 mm, diameter 0.07–0.17 mm in segment VII and 0.08– 0.22 mm in segment XII. Number of segments 23–28. Chaetae two per bundle, formula 2, 0–0: 2–2. Chaetae straight, with proximal bend. Lateral chaetae present in II–VII, absent from VIII on, ventral chaetae absent in XII in mature worms (Figure 2a). Ventral chaetae in preclitellar segments ca. 25–30 μm long and 2.5 μm thick (Figure 3d), increasing in size behind clitellum towards posterior end, ca. 32.5–45 μm long and 2.5–4 μm thick (ca. 1.5× as large as anterior). Prostomium with head pore in mid-dorsal position, slit transverse (Figure 2a). Epidermal gland cells grey, inconspicuous, cells almost round (diameter ca. 2.7–4 μm, in vivo) and evenly distributed in 7–8 separate transverse rows per segment (Figure 4d). Clitellum in XII–1/2XIII, conspicuous thickening, saddle-shaped, clitellum-free mid-ventral field as wide as distance between male pores. Cells in dense transverse rows, roughly rectangular, with hyalocytes (ca. 19–25 μm high and 11–13 μm wide, in vivo) larger than granulocytes (ca. 11–25 μm high and 7.5–10 μm wide, in vivo); with larger proportion of hyalocytes dorsally, and larger proportion of granulocytes laterally (Figures 2a, 4e, f). Body wall thin, 7–12 μm thick, cuticle in vivo). Brain about 2 × as long as wide (ca. 50 μm wide and 100 μm long, in vivo), incised posteriorly, sides converging anteriad (Figures 2a, b, 3a). A pair of prostomial ganglia present on prostomial nerves (Figures 2a, b, 3a). Pharyngeal glands with two unpaired dorsal lobes in IV and V, of almost the same size; primary ventral lobes in V, elongate; secondary ventral lobes in V and VI, spherical, smaller than primary ventral lobes. In VI–VII a pair of separate elongate lobes, consisting of an anterior dorsal part in VI and a posterior ventral part in VI–VII (Figures 2a, 3c). Oesophageal appendage and intestinal diverticula absent. Gut widening gradually in VII (Figure 2a). Chloragocytes inconspicuous, from V, and dense from VII. Dorsal vessel originating from XII–XIII, blood colourless. Nephridia two pairs in preclitellar segments, at 7/8 and 8/9 (Figures 2a, 3e). Anteseptale with funnel and parts of nephridial body, funnel attached obliquely, anteseptale about 26 μm long and 22 μm wide (in vivo); postseptale larger than anteseptale (ca. 40 μm long and 26 μm wide, in vivo), with a dorsal bump in mid-section; nephridial canal apparently with up and down zig-zag course; efferent duct rising subterminally, nephroporus inconspicuous, situated anteriorly of ventral chaetal bundles, no terminal vesicle. Nephridia in postclitellar segments in varying positions. Coelomocytes one type, nucleate mucocytes slightly longer than wide ca. 17–24 μm long (in vivo); cells brownish in vivo, with small spherical and refractile vesicles (Figure 3f). Seminal vesicle absent. Spermatozoa conspicuous at the opening of sperm funnel, ca. 40 μm long, head ca. 14 μm long (in vivo) (Figure 2a, c). Sperm funnel pear-shaped, with distinct collar, not or only a little wider than funnel body; sperm funnel small, ca. 40 μm long and 26 μm (at collar) wide (in vivo) (Figures 2a, c, 4a). Vas deferens in loose or dense coils ventro-laterally, diameter ca. 5 µm (in vivo) (Figures 2a, 4c). Male copulatory organ inconspicuous, glandular bulb with musculature (Figures 2a, 4f), roughly spherical, ca. 32 μm in diameter (in vivo). No accessory copulatory glands. Spermathecae free, not attached to oesophagus, like a proximally blind-ending tube, confined to V; ectal pores lateral at 4/5, without ectal glands, ectal ducts short (64 µm long, 10 µm wide, in vivo), ampullae wider than ectal ducts (28 µm long, 16 µm wide, in vivo) with thin wall, empty or with spermatozoa (Figures 2a, 3b). Two mature eggs at a time, occupying 3–4 segments (Figures 2a, 4b). Remarks The new species is most similar to Xetadrilus maacki Schmelz, 2011, which also has two pairs of preclitellar nephridia, brown coelomocytes, spermathecae confined to V and intestine widened in VII. However, in X. maacki the pharyngeal glands are dorsally united in VI and there are three pairs of secondary ventral lobes in V–VII. Further conspicuous differences of X. maacki from the new species include sigmoid chaetae in posterior segments and epidermal gland cells only mid-ventrally. A comparison of X. prolixglandus sp. nov. with similar species is presented in Table 4. Molecular analyses confirm that X. prolixglandus sp. nov. is a species distinct from other Xetadrilus species for which sequences are currently available, since its sequences form distinct lineages on the phylogenetic trees based on the COI region (Figure 5). However, our analysis is limited by the lack of sequence data for other species of Xetadrilus., 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 1962-1967, DOI: 10.1080/00222933.2022.2140085, http://zenodo.org/record/7426634, {"references":["Schmelz RM, Collado R, Rombke J. 2011. Mata Atlantica enchytraeids (Parana, Brazil): a new genus, Xetadrilus gen. nov., with three new species, and four new species of Guaranidrilus Cernosvitov (Enchytraeidae, Oligochaeta). Zootaxa. 2838 (1): 1 - 29. doi: 10.11646 / zootaxa. 2838.1.1."]}

Enchytraeus sp., buchholzi group (Enchytraeus buchholzi; Vejdovský, 1879) (Figures 11, 12) = Enchytraeus florentinus Bell, 1947 = Enchytraeus polonicus Dumnicka, 1977 Enchytraeus buchholzi Vejdovsky, 1879; Nielsen and Christensen, 1959; Dash 1970; Chalupský 1992; Rota and Healy 1994; Rota 1995; Schmelz et al. 2005; Schmelz and Collado 2010. Material investigated CJJ 95, one submature specimen from site 7, whole worm used for DNA extraction, preserved as total DNA. One submature specimen from site H and two submature specimens from site 7, preserved in 75% ethanol. Description Small worms, yellowish white in stereomicroscope. Length ca. 3.3–5.0 mm (in vivo), 1.8– 2.8 mm, wide 122.5–180.0 μm in segment VII and 125–200 μm in clitellum. Number of segments 24–25. Chaetae straight, with ental hook, formula: 2–2, 3: (2) 3–3 (2). Head pore at 0/1, transverse slit (Figure 11a). Epidermal gland cells grey, inconspicuous, 4–5 transverse rows per segment. Clitellum in XII–1/2XIII, saddle-shaped, hardly elevated, not fully developed (our specimens are all submature). Body wall ca. 15–26 μm thick (in vivo). Brain trapezoidal, truncate anteriorly and round posteriorly, ca. 124 μm long, 46 μm wide anteriorly and 86 μm wide posteriorly (in vivo) (Figures 11b, 12a). Oesophageal appendages a pair of unbranched tubes with common opening leading dorsally into oesophagus in III, behind pharyngeal pad, tubes extending into IV with meandering cannel (Figures 11a, 12b). All three pairs of pharyngeal glands separated dorsally, pharyngeal gland in VI elongate, with a small constriction at septum (Figures 11a, 12d). Dorsal vessel from XII–XIII, blood colourless. Intestinal diverticula absent, gut widening gradually. Chloragocytes well developed, large and with retractile globules of differing size, present from V and forming a dense layer from segment VII onward, absent in XII (Figures 11a, 12e). Four pairs of preclitellar nephridia from 6/7–9/10, anteseptale with funnel only. Coelomocytes one type, mucocytes, with refractile granula. Seminal vesicle absent. Spermatozoa sparse, ca. 37 μm long and head ca. 15 μm long (in vivo) (Figures 11c, 12f). Sperm funnel cylindrical, small, length about 1/4 body diameter (ca. 33 μm long and 17 μm wide, in vivo), with distinct midline, collar little wider than funnel body (Figures 11c, 12f). Vas deferens long, in tangled coils ventro-laterally, diameter ca. 6 µm (in vivo) (Figure 12f). Male copulatory organ small, globular, not floppy. Spermathecae short, confined to V; ectal pores lateral at 4/5, surrounded by several glands at each pore, glands of varying size, sometimes stretching along ectal duct; ectal ducts ca. 52 μm long and 9 μm wide (in vivo); ampullae spindle-shaped, ca. 43 μm long (in vivo), almost with same diameter as ectal ducts; ental ducts short and narrow; spermathecae attached to oesophagus separately (Figures 11a, 12c, d). No mature eggs observed. Remarks Using the key for European species in Schmelz and Collado (2010), specimens key out as E. buchholzi Vejdovský, 1878, based on the following characters: chaetal formula 2–2, 3: 3–3, oesophageal appendage with meandering canals, four pairs preclitellar nephridia, in 6/7 to 9/10, clitellum saddle-shaped, testis sac, sperm funnel and male glandular bulb small, spermathecal ectal glands covering only ectal part of ectal duct, ampulla small, ental duct present. Enchytraeus buchholzi is a species complex (Rota and Healy 1994; Rota 1995; Schmelz et al. 2005). Descriptions of this species sensu lato usually distinguish two forms based on the texture of the coelomocytes: with or without refractile granula (Schmelz et al. 2005). Specimens from Mount Fanjing have coelomocytes with refractile granules. All specimens are submature, i.e. without eggs or a fully developed clitellum. This record documents the presence of E. buchholzi sensu lato at Mt. Fanjing. It is unknown whether the specimens underlying this account belong to one or more species. In China, E. buchholzi has also been recorded fromMount Changbai, Jilin Province (J.J. Chen, unpublished data). The K2P distances based on COI sequences also confirm the complexity of E. buchholzi. The genetic distance between our specimens and E. buchholzi - Russia (Erséus et al. 2010), E. buchholzi - Switzerland (Vivien et al. 2015) and E. buchholzi - India (GenBank accession number: KX348269) are 18.7%, 20.7% and 19.9%, respectively. However, we failed to match molecular differences to morphological differences because of the lack of morphological descriptions., 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 1975-1979, DOI: 10.1080/00222933.2022.2140085, http://zenodo.org/record/7426634, {"references":["Vejdovsky F. 1879. Beitrage zur vergleichenden Morphologie der Anneliden. I. Monographie der Enchytraeiden. Verlag von Friedrich Tempsky. 61.","Bell AW. 1947. Some new enchytraeids (Oligochaeta) from the old world. Trans Am Microsc Soc. 66 (2): 190 - 202. doi: 10.2307 / 3223250.","Dumnicka E. 1977. Enchytraeus polonicus sp. n., a new species of Enchytraeidae (Oligochaeta) from a cave in the Krakow-Czestochowa Upland. Bulletin de l'Academie Polonaise des Sciences, Serie des sciences biologiques Classe II. 25: 163 - 166.","Nielsen CO, Christensen B. 1959. The Enchytraeidae. Critical revision and taxonomy of European species (Studies on Enchytraeidae VII). Natura Jutlandica 8 - 9: 1 - 160.","Dash MC. 1970. A taxonomic study of Enchytraeidae (Oligochaeta) from Rocky Mountain forest soils of the Kananaskis region of Alberta, Canada. Can J Zool. 48 (6): 1429 - 1435. doi: 10.1139 / z 70 - 242.","Chalupsky J. 1992. Terrestrial Enchytraeidae (Oligochaeta) and Parergodrilidae (Polychaeta) from Sweden, with description of a new enchytraeid species. Zool Scr. 21 (2): 133 - 150. doi: 10.1111 / j. 1463 - 6409.1992. tb 00316. x.","Rota E, Healy B. 1994. The enchytraeid fauna of North Africa. Hydrobiologia. 278 (1 - 3): 53 - 66. doi: 10. 1007 / BF 00142311.","Rota E. 1995. Italian Enchytraeidae (Oligochaeta). I. Ital J Zool. 62: 183 - 231. doi: 10.1080 / 11250009509356067","Schmelz RM Arslan N, Bauer R, Didden W, Dozsa-Farkas K, Graefe U, Panchenko I, Pokarzhevski A, Rombke J, Schlaghamersky J, et al. 2005. Estonian Enchytraeidae (Oligochaeta) 2. Results of a faunistic workshop held in May 2004. Proc Est Acad Sci Biol Ecol. 54 (4): 255 - 270. doi: 10.3176 / biol. ecol. 2005.4.02","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.","Vivien E, Wyler S, Lafont M, Pawlowski J. 2015. Molecular barcoding of aquatic oligochaetes implications for biomonitoring. PLoS ONE. 10 (4): 1 - 15. https: // journals. plos. org / plosone / article / file? id = 10.1371 / journal. pone. 0125485 & type = printable"]}