Research Article |
Corresponding author: Barna Páll-Gergely ( pallgergely2@gmail.com ) Academic editor: Frank Köhler
© 2015 Barna Páll-Gergely, András Hunyadi, Takahiro Asami.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Páll-Gergely B, Hunyadi A, Asami T (2015) A new Chinese species of Eostrobilops Pilsbry, 1927 with a checklist of Eostrobilops and Enteroplax Gude, 1897 species (Gastropoda, Pulmonata, Strobilopsidae). ZooKeys 508: 85-95. https://doi.org/10.3897/zookeys.508.10004
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Eostrobilops humicolus Páll-Gergely & Hunyadi, sp. n. is described from Guangxi Province, China. It is characterized by the combination of a small shell (diameter: 2.3–2.4 mm), strongly ribbed dorsal surface, an infraparietal lamella not reaching the callus, and long basal folds. The new species is found approximately 500 and 800 km from the two nearest species E. infrequens (northern Vietnam), and E. diodontina (Hunan, China), respectively. A checklist of extant Eostrobilops Pilsbry, 1927 and Enteroplax Gude, 1899 species is provided. Enteroplax yaeyamensis Habe & Chinen, 1974, Enteroplax kanjiokuboi Minato & Tada, 1992 and Enteroplax taiwanica Minato & Tada, 1992 are moved to the genus Eostrobilops because of the lack of an elevated parietal callus and a peripheral thread. A map showing all Eostrobilops records is provided.
Revision, taxonomy, systematics, land snail
The family Strobilopsidae is mainly defined on a conchological basis; the shell is trochiform, dome-shaped or discoidal, umbilicate and consists of 4.5–6 slowly increasing whorls. The aperture is oblique, peristome more or less thickened and expanded; the ends of the lips are connected by a parietal callus. The main characteristic feature of the family is the armature consisting of two or three parietal lamellae and several deeply-placed basal folds, all growing continuously from an early neanic state (
Living Strobilopsidae occur in America, from northern Mexico to the northern part of South America, and East Asia, from North Korea and south-eastern Russia to southern Borneo (
East Asia is inhabited by two recent strobilopsid genera: Enteroplax Gude, 1899 and Eostrobilops Pilsbry, 1927, which differ from each other in the morphology of the parietal callus, the edge of the body whorl and the parietal lamellae. Herein, we describe a new species of Eostrobilops from the Chinese province of Guangxi and provide a critically revised checklist of Eostrobilops and Enteroplax species.
The nomenclature for the armature follows that of
Comparative material. Eostrobilops hirasei, Korea, Quelpart (= Cheju Island), det. Zilch (?), NHMUK 1909.2.20.112.114.; Eostrobilops nipponica (labelled as matsushimae), Japan, Uzen, NHMUK 1912.6.28.19–20, NHMUK 1912.6.29.32–34; Eostrobilops coreana, 朝鮮京城府北渓山 (probably Cho-Sen Kei-Joh-Fu, Hoku-Kei-Zan), Sakurai collection, NSMT/2; Eostrobilops kanjiokuboi, 中華民国 (台湾) 南投県信義郷東埔楽々温泉, Lo lo uen chuan, Tung-pu, Hsin-i shiang, Nan tou hsien, Taiwan, NSMT 69652/1 paratype; Eostrobilops diodontina, China, Tchen-k’eou, leg. Farges, excoll Musée Heude, 03.01.1946, MCZ, 167133 (photos of a syntype were received from Jochen Gerber). We could not examine most Eostrobilops types during our visit to the National Museum of Nature and Science, Tsukuba, Japan (11–13 March, 2015), because they were on loan. The comparisons of Eostrobilops humicolus sp. n. with E. infrequens and E. triptychus were based on the original descriptions of these species.
HA Collection András Hunyadi, Budapest, Hungary
HNHM Hungarian Natural History Museum, Budapest, Hungary
MCZ Museum of Comparative Zoology, Massachusetts, USA
NHMUK The Natural History Museum, London, United Kingdom
NSMT National Museum of Nature and Science, Tsukuba, Japan
Eostrobilops Pilsbry 1927 (as a section of Strobilops), Manual of Conchology, Second Series, 28: 42.
Strobilops hirasei Pilsbry, 1908, by original designation.
China, Guangxi (广西), Hechi Shi (河池市), Tiane Xian (天峨県), Qimu Xiang (豈暮郷), road junction toward Lahaoyan (拉号岩), cliff overlooking a memorial, 600 m, 24°51.130'N, 107°11.670'E, leg. Hunyadi, 12.09.2013., HNHM 99419 (holotype, Figure
A small Eostrobilops species with a strongly ribbed dorsal surface, an infraparietal lamella not reaching the callus, and long basal folds.
Shell small, light brown (only one shell in type material had original colour); trochiform, rather domed above, almost flat ventrally (umbilical side), periphery rounded, very slightly keeled, suture rather deep; 4.75 (n = 3) slowly expanding whorls, protoconch approximately 1.5 whorls; virtually smooth but with weak microscopic pits arranged in irregular radial lines; teleoconch irregularly ribbed; ribs strong dorsally, very weak ventrally (except for inside the umbilicus); spiral structure entirely lacking; umbilicus narrow; inner margin of the whorls exposed in umbilicus irregularly crenulated; aperture semilunar and oblique; peristome slightly thickened and slightly reflexed; parietal callus weak; parietal and infraparietal lamellae well-developed, although the infraparietal does not extend to the peristome; a low interparietal lamella deeply situated, not visible from aperture; three long basal folds and one short columellar lamella; basal folds visible in one specimen with a fresh, translucent shell only (Figs
Both E. hirasei and E. nipponica are much larger than the new species, they have a more rounded body whorl, wider umbilicus, and weaker dorsal sculpture. Eostrobilops coreana is larger and flatter than E. humicolus sp. n., has a weaker dorsal sculpture, both of its parietal lamellae extend to the peristome, and has a shorter basal folds. Eostrobilops kanjiokuboi is similar to E. humicolus sp. n. by having a strongly ribbed dorsal surface and long basal folds, but differs in the larger size, wider umbilicus, and the serrated lamellae (not serrated in E. humicolus sp. n.); the infraparietal lamella extends to the callus (not in E. humicolus sp. n.), and has a long palatal fold, which is lacking in the new species. Eostrobilops diodontina is slightly larger (D = 2.88, H = 1.75 mm), has more elevated parietal and infraparietal lamellae, and both lamellae attain the peristome. Moreover, E. diodontina has shorter basal folds. Eostrobilops infrequens has a more elevated spire than E. humicolus sp. n., a stronger callus, a narrower umbilicus and shorter basal folds. The spire of E. triptychus is higher, it has more angulate periphery, thicker peristome and shorter basal folds.
(in mm): D = 2.3–2.4, H = 1.45–1.5 (n = 2).
From Latin (‘humicolus’ = soil-dwelling), in reference to the fact that this species was found in soil samples.
No living specimens have been found. The empty shells were collected from a soil sample. Eostrobilops humicolus sp. n. probably lives under stones and dead leaves on the soil.
China, Guangxi (广西), Hechi Shi (河池市), Tiane Xian (天峨県), Qimu Xiang (豈暮郷), road junction toward Lahaoyan (拉号岩), cliff overlooking a memorial, 600 m, 24°51.130'N, 107°11.670'E.
Known from the type locality only.
Eostrobilops yaeyamensis, E. taiwanica and E. kanjiokuboi have been described as Enteroplax species. However, they lack the thickened parietal callus, which is conspicuous in every Enteroplax species. Moreover, although they have a somewhat angular periphery, they lack a distinct “peripheral thread”, which is also characteristic for Enteroplax. Therefore, all these three species belong to the genus Eostrobilops, as already proposed by
No obvious teleoconch spiral lines are visible in the photo of the syntype of Eostrobilops diodontina, as noted in the original description (
The palatal fold, which is approximately a quarter whorl in length and runs just above the keel in the paratype of E. kanjiokuboi (see Material and methods) was not mentioned in the original description.
Enteroplax dumogensis Vermeulen, 1992: Indonesia, North Sulawesi Island, Utara, Dumoga valley, Mount Mogogonipa (
Enteroplax misoolensis (Adam & van Benthem Jutting, 1939): Indonesia, Misool Island, near Lilinta, Waima and Fakal (
Enteroplax polyptychia (Möllendorff, 1887): Philippine Islands, Cebu and Siquijor Islands (
Enteroplax quadrasi (Moellendorff, 1893): Philippine Islands, Luzon, Bohol, Mindanao islands (Moellendorff 1893,
Enteroplax trochospira (Möllendorff, 1887): Philippine Islands, Cebu and Bohol islands; Indonesia: North Sulawesi (
Eostrobilops coreana (Pilsbry, 1927): North Korea: Pyong Yang; southeast Russia, National reserve “Kedrovaya pad” (Кедровая падь = “Cedar valley”) (
Eostrobilops coreana echo (Kuroda & Miyanaga, 1939): North Korea, Soto-Kongō (outer Kumgang Mountains) (
Eostrobilops diodontina (Heude, 1885): Tchen k’eou (=Chengkou, Chongqing Province, China) (
Eostrobilops hirasei (Pilsbry, 1908): South Korea, Quelpart Island (
Eostrobilops infrequens Maassen, 2006: Vietnam, Thanh Hoa Province, Pu Luong National Park (
Eostrobilops kanjiokuboi (Minato & Tada, 1992): Lo lo uen chuan, Tung-pu, Hsin-i shiang, Nan tou hsien, Taiwan (
Eostrobilops kongoensis (Kuroda & Miyanaga, 1939): North Korea, near Tyō-anzi, Uti-Kongō (=Kumgang Mountains;
Eostrobilops humicolus Páll-Gergely & Hunyadi, sp. n.: China, Guangxi, Hechi Shi, Tiane Xian, Qimu Xiang, cross towards Lahaoyan, 600 m, 24°51.130'N, 107°11.670'E.
Eostrobilops nipponica (Pilsbry, 1927): Japan, Yonezawa; Nagano Province (
Eostrobilops nipponica reikoae Matsumura & Minato, 1980: Japan, Osaka Prefecture, Takatsuki-shi, Ibaragi-shi, Suita-shi and Minoo-shi (fourteen localities; Matsumura and Minato 1980).
Eostrobilops taiwanica (Minato & Tada, 1992): Meifeng, Lenai shiang, Nan tou hsien, Taiwan (
Eostrobilops triptychus Vermeulen, 1992: Indonesia, Borneo, Kalimantan Selatan, northwestern part of the Meratus Mountains (
Eostrobilops yaeyamensis (Habe & Chinen, 1974): Sonai, Irimote Island; Kabira, Ishigaki Island (both Yaeyama Group, Okinawa, Japan) (
Distribution of Eostrobilops species. 1, 2 Eostrobilops coreana (Pilsbry, 1927) 3 E. coreana echo (Kuroda & Miyanaga, 1939) and E. kongoensis (Kuroda & Miyanaga, 1939) 4, 5 Eostrobilops nipponica (Pilsbry, 1927) 6 E. nipponica reikoae Matsumura & Minato, 1980 7 E. hirasei (Pilsbry, 1908) 8 E. diodontina (Heude, 1885) 9 E. humicolus sp. n. 10 E. kanjiokuboi (Minato & Tada, 1992) and E. taiwanica (Minato & Tada, 1992) 11 E. yaeyamensis (Habe & Chinen, 1974) 12 E. infrequens Maassen, 2006 13 E. triptychus Vermeulen, 1992.
We are very grateful to Anatoly Schileyko, Kurt Auffenberg and Zoltán Fehér for providing literature, Jonathan Ablett (NHM), Kazunori Hasegawa (NSMT) for providing access to museums collections, Roland Farkas for his help in producing the map, Kurt Auffenberg for fine-tuning the English and Yurika Ujiie for her help for handling label data. This study was supported by scholarships from Japan Student Services Organization and Mitsubishi Corporation to BPG and Grants-in-Aid for Scientific Research (KAKENHI) from Japan Society for the Promotion of Science to T.A.