Metaphire liaoningensis Han & Zhao 2025, sp. nov.
Creators: name: Zhao, Huifeng
name: Han, Anne Charis N.
name: Liu, Min
name: Zhang, Yufeng
name: Aspe, Nonillon M.
name: Miao, Pu
name: Wu, Donghui
Publisher: name: Zenodo
Year: 2025
Subjects: Biodiversity
Taxonomy
Animalia
Annelida
Clitellata
Crassiclitellata
Megascolecidae
Metaphire
Metaphire liaoningensis

description: Metaphire liaoningensis Han & Zhao sp. nov.
Figs 1, 2
Material examined.
Holotype: • 1 clitellate (368 R 6_02), Wanquan Park (41.7884 ° N, 123.4659 ° E, 57 m elev.), Shenyang Prefecture, Liaoning Province, 2023-07-01. Paratypes: • 4 clitellates (368 R 6_01, 368 R 6_04, 368 R 7_01, 368 R 7_02), same data as of holotype; • 1 clitellate (359 R 4_05), Zhongshan Park (41.7835 ° N, 123.4012 ° E, 60.4 m elev.), Shenyang Prefecture, Liaoning Province, 2023-07-01. Other specimens: • 2 juveniles (359 R 4_03, 359 R 5_03), the same with 359 R 4_05; • 1 juvenile (551 _ 13), Shuangshu Town (40.7060 ° N, 120.7910 ° E, 25.0 m elev.), Huludao Prefecture, Liaoning Province, 2023-07-27; • 2 juveniles (319 R 11_04, 319 R 31_04), People’s Park (43.5964 ° N, 122.2848 ° E, 183.5 m elev.), Tongliao Prefecture, Inner Mongolia Autonomous Region, 2023-07-24. All above specimens were collected by Yufeng Zhang, Shixiong Ma, Min Liu, and Mingyan Qin. All the specimens are stored at the Hebei Key Laboratory of Animal Diversity, Langfang Normal University, Langfang, China (C-HLU).
Etymology.
The specific name refers to the first known distribution range, which is in the Liaoning Province, Northeast China.
Diagnosis.
Medium sized, length 125–200 mm, diameter 6.0–7.0 mm, number of segments 120–145. Prostomium epilobic. First dorsal pore on 12 / 13. Three pairs of spermathecal pores in 6 / 7 / 8 / 9, ventrolaterally positioned. Male pore in XVIII in copulatory pouches (everted); ventral distance between openings of the pouches about 3.4–4.5 mm. Preclitellar genital markings small and prominently rounded. Intestinal caeca simple. Septa 8 / 9 / 10 absent. Spermathecael ampulla nearly elliptical, large, surface wrinkled, ampulla duct long, stout with a swollen basal portion. Diverticulum originating from below the swollen portion of the spermathecal duct, stalk slender at the proximal end, enlarged and greatly coiled toward distal end. Accessory glands, sessile, small and round. Prostate glands paired in XVIII, very follicular, extending anteriorly to XV (or XVI) and posteriorly to XX (or XXI), divided into many finger-shaped pieces. Prostatic duct U-shaped and slender.
Description.
External characters. Length 125–200 mm (n = 6). Color of preserved specimens may vary in shades because of the duration of preservation, but generally, dorsum region brown, covering half of the body length and fading to lighter brown towards posterior end with darker brown clitellum, while ventrum part is yellowish brown. Width 6.0–7.0 mm, segments 120–145. Prostomium epilobous (Fig. 1 A). First dorsal pore on 12 / 13. Clitellum annular at XIV – XVI; setae or dorsal pores and intersegmental furrow absent. Setal arrangement perichaetine; setae number 43 (V), 56 (IX), 70 (XIII). Setae between male porophores: 12–20 (20 setae count if reaching on porophore). Female pore single in slit-like opening, medioventral at XIV.
Spermathecal pores three pairs, 6 / 7–8 / 9, ventrolateral; each pore is located inside a transverse slit cave-like opening with ridges in the lip opening, 0.28–0.30 C apart ventrally. Pre-clitellar genital markings small and prominently rounded with diameters ranging from 0.3 to 0.6 mm, presetal on VII, XIII, and IX, 2–6 genital markings (rarely absent or with inconspicuous genital markings), paired or unilateral (rarely), located medio-vental to spermathecal pore slit opening, widely spaced 0.21–0.26 C apart ventrally (Fig. 1 B).
Male pores paired in XVIII (Fig. 1 D), situated ventro-laterally at everted copulatory pouches (diameters ranging 1.8–2.5 mm); ventral distance between openings of the pouches 3.4–4.5 mm. All specimens displayed everted copulatory pouches and 2– 3 male pore tubercles in each porophore (upper tubercles larger than lower tubercles). Post-clitellar genital marking absent.
Internal characters. Septa 8 / 9 / 10 aborted, 5 / 6 / 7 / 8 thick and muscular, 10 / 11 / 12 / 13 uniform thickness, 13 / 14 slightly thickened. Gizzard within IX – X (or only IX), small. Intestine enlarged from XV. Intestinal caeca are simple, originating in XXVII and extending anteriorly to XXIII (Fig. 1 C); however, some caeca extend up until XX. Last pair of hearts in XIII.
Spermathecae (Fig. 1 E) three pairs in VII – IX, ampulla nearly elliptical, large, surface flattened and wrinkled, 2.2–4.2 mm long, 2.0– 2.8 mm wide; ampulla duct long, stout, 1.4–1.5 mm long, with a swollen basal portion, 1.2–1.3 mm wide; diverticulum originating from below the swollen portion of the spermathecal duct, stalk slender at the proximal end 1.2–2.3 mm long, enlarged and greatly coiled toward distal end, receptacle is 2.2–3.6 mm long. Accessory glands, sessile, small and round. Variations of spermathecae are shown in Fig. 2.
Testis sac one pair, connected, in XI. Seminal vesicles are two pairs in XI and XII, well developed, follicular, posterior pair larger, each with a round or oval dorsal lobe. Prostate glands (Fig. 1 F) large, paired in XVIII, follicular, divided into many finger-shaped pieces, extending anteriorly to XV (or XVI) and posteriorly to XX (or XXI). Prostatic duct U-shaped, slender.
Distribution.
Northeastern China (Liaoning province and eastern Inner Mongolia Autonomous Region).
Habitats.
Municipal parks.
Remarks.
M. liaoningensis sp. nov. is classified into the M. houlleti species group (Sims and Easton 1972), which includes an estimate of 47 named species (Blakemore 2016). This group is characterized by having three pairs of spermathecal pores in 6 / 7 / 8 / 9, a male pore on XVIII, bithecate, and post-clitellar genital markings absent (Sims and Easton 1972). Currently, China has recognized 23 species belonging to the M. houlleti species group, of which 20 species were recorded by Xiao (2019) and M. sanmingensis by Sun et al. (2018), and two recently identified species, M. donganensis (Jin & Jiang, 2024) and M. hanbaiduensis (Dong & Sun, 2024) from southern China. However, only 10 of these species have been recognized in Blakemore (2007 b), mainly due to the known species recorded at that time and some changes at the genus and subspecies levels.
Collected specimens of the new species were all observed to have everted copulatory pouches and exhibit male pore tubercles. Table 2 presents a comparison of morphologically similar members of the M. houlleti species group in China with M. liaoningensis sp. nov. Among all the M. houlleti species group species in China, the new species is clearly seen to be unique from the rest by having round and prominent pre-clitellar genital markings reaching up to a maximum of three pairs and having a large and flattened ampulla with a swollen base of the ampulla duct. Although live specimens of M. liaoningensis sp. nov. share similar outward morphological characters (such as size and pigmentation) with M. tschiliensis, internal structures differ, such as in the shape of the spermathecae ampulla, diverticulum length, and prostate gland structures.
In addition, M. liaoningensis sp. nov. differs from the other morphologically similar species with dorsal pore in 12 / 13 by the following specific traits: pre-clitellar genital markings present [vs. present or absent in M. vulgaris agricola (Chen, 1930) and M. tschiliensis], accessory glands present and sessile [vs. present and stalked in M. kokoana (Chen & Fong, 1975) and M. aggera (Kobayashi, 1934); vs. absent in M. tschiliensis, M. guillelmi; and vs. bundle of strands in M. vulgaris agricola].
Moreover, it may seem that the new species also has some internal similarities to M. houlleti (Perrier, 1872), such as the very follicular prostate gland with a slender U-shaped duct, yet the follicle coverage according to segment count and number differs. These differences may be attributed to the body size of the species, since M. houlleti specimens are smaller than those of the M. liaoningensis sp. nov. specimens.
Likewise, other species of the M. houlleti species group, which are non-endemic to China, such as M. acampanulata in Vietnam, which share similar size with M. liaoningensis sp. nov., also manifested obvious dissimilarities in both external and internal morphologies, such as the presence and count of genital markings on both pre-clitellar and post-clitellar regions, the presence of penial setae, the orientation of accessory glands, the ampulla shape and size, and the diverticulum length.
description: Published as part of Zhao, Huifeng, Han, Anne Charis N., Liu, Min, Zhang, Yufeng, Aspe, Nonillon M., Miao, Pu & Wu, Donghui, 2025, A new pheretimoid earthworm of the genus Metaphire Sims & Easton, 1972 (Oligochaeta, Megascolecidae) from northeastern China with data from the mitochondrial genome, pp. 81-89 in Zoosystematics and Evolution 101 (1) on pages 81-89, DOI: 10.3897/zse.101.136027