The malacologicalsocietymalacological society ofJapanof Japan

fige YENUS (Jap. Jour. Malac.) Vel. 45, Ne. 3 C19S6): 169-176

-? tsgOlijEze< . Rzl

,ji Mlr N ee ([llkJit#mp\zzwu'tsfireimbeecuant)

Freshwater and Brackish Water Neritid Fauna in Taiwan (Republic of China)"

Shigemi KoMATsu

(Mukaishima Marine Biological Station of Hiroshima University,

Mukaishima-cho, Hiroshima-ken 722)

Abstract: The present paper deals with freshwater or brackish water neritid

fauna in northern and central Taiwan. Twelve species in three genera (eight

subgenera) were colleeted, of which five species are new reeords from Taiwan, and all of them are also distributed in Japan. There is a high zoogeographical

aMnity between Taiwanese and Japanese neritid fauna.

Matsuda (1924a, b), Herikawa (1935a, b), Kuroda (1941) and Pace (1973)

have previously reperted on neritid fauna in Taiwan (Republic of China).

Kureda listed 26 species in five genera, of which the freshwater or brackish

water neritids are composed of one speeies in the genus Nerita, three in the

genus Clithen, four in the genus Neritina and one in the genus Septaria. Pace

made a detailed review on the Taiwanese freshwater snails among which he

dealt with four species of Clithon, four of Neritina and one of Septaria. As a

part of the taxonomie study ef Japanese neritids, the comparison ef the Japa-

nese speeies with the Taiwanese speeies is made in order to elucidate a faunal

relationships within Neritidae and to eontribute new knowledge on freshwater

neritid fauna in Taiwan.

Materials

Specimens used in this study were eolleeted at the rivers of northern or

central Taiwan in April, 1985. Their localities are as follows (Map 1) : 1. Tungkang, I-lan (Lanyang Hsi).

2. Taichung (Tachia Hsi).

3. Takangko. ttt t tttt t tt t * Contribution from the Mukaishirna Marine Biological Station, No. 273;

Aceepted: May 12, 1986

NII-Electronic Library Service The malacologicalsocietymalacological society of Japan

170 VENUS: Vol. 45, No. 3 (1986)

gtianLiaochiav

mfo benghub Islants

e

KHohs

Map L Collecting localities. tweeJa±l,E,, 1, Tungkang, I-lan (Lanyang Hsi). Mas, :A:carii (whuzpt) 2, Taichung (Tachia Hsi). kgbi+i (]krpec) 3. Takangko, Jknsn

Results

Genus Ceithon Montfort, 1810

Subgenus Clithon s. str.

1. CZithon (CZithon) oorona (Linnaeus, 1758). (Fig. 1)

Localities oncl habitats: Takangko, 8 specimens; Tachia Hsi, 39 specimens.

Many snails were found attached on stones in the estuaries. These loealities

are the new distributional records in the central Taiwan.

Distribution in Tai2van: Kuroda (1941) reported this speeies enly from Keelung. Paee (1973) has also eited Kuroda's record and showed that a form

from the Philippines was C. c. angutosa.

2. (;Zithon ((;Zithon) retropictus (v. Martens, 1879). (Fig. 2) Localities and habitats: Tachia Hsi, 1 specimen. It inhabited the same area

as C. corona. This locality is a new distributional record in the central Taiwan,

Distribution in Taiwan: Hsinchu (Horikawa, 1935a, b) ; Keelung, Tanshui, Tali, Santiaochiao (Kuroda, 1941); I-lan, Taipei (Pace, 1973).

3. ()tithon (crithon) faba (Sowerby, 1836). (Fig. 3) Loeatities and habitats: Lanyang Hsi, 1 specimen; Taehia Hsi, 9 speeimens.

This species inhabited the same areas as C. corona,

Distribution in Taiwan: Tanshui (Martens, 1879; Pace, 1973); Liuchiu Yu

(Matsuda, 1924a).

NII-Electronic Library Service The malaoologloalmalacological societysoolety of Japan

Komatsu ： Freshwater Neritid Fauna in Taiwan ． 171

’ 一 ；i ・・：：： ・ ：ii蘇 ・鵬 謙 難iilii 隙 嫉 li 3

「囁 ミttt 照揮 』 睾緜 痴 肝 §匿 脚・ 噸驫 叢 黙 鑑二認 i ’ ・ ． ： ： 鑑 認 堀 iil7 ，：：：；．蕊ill： 雌難 鑞 嬬鍛 1鑓il

’ ’ ’ げ’ ’ほ：にu ， ，ニ こttU ミt 、t ttt’ r− ’ ・ 臓 ：：：…；1鑞i8i：、：：ili≡欝ii；；： tt ；一 ・：嵩 ン遣遣囁藩 ：溝O ！i鳧t彈tt’til；；｝：淫議 ：： 曽””／SMU ”／遥 ：／ ：tt・tmt・・tttt

簔：， ’tt 訟 ・灘鮒w” tt・t ■ ， 騾

Fig． L Ctithon （Clithon） corona （Linnaeus，1758）． Takangko ． イ ガ カ ノ コ ガ イ （大港 口 産 ） 2． C．（C ．） retropictus （v ， Martens ，1879）． Tachia Hsi ． イ シ マ キ ガ イ （大 甲渓 産） 3． C ，（C ．）faba （Sowerby ，1836）． Tachia Hsi． カ ノ コ ガ イ （大 甲渓産） ハ コ 4． C．（Pictoneritina）chlorostema （Sowerby ，1833）． Takangko ． ナ ガ ス ミ カ ノ ガ イ （大 港 「1産 ） 5 ． Neritina （Neripteron ） auriculata Lamarck ，1816． Lanyang Hsi ソ バ サ カ ノ コ ガ イ （蘭陽 渓産） ． Lanyang Hsi ． ヒ 卩 ク チ カ ノ コ ガ イ 678901 コ N ．（1）ostia ） viotacea （Gmelin ，1791） （蘭陽 渓 産 ） コ N ．（Vittina） turrita （Gmelin ，1791）． Lanyang Hsi ． シ マ カ ノ コ ガ イ （蘭 陽渓 産 ）

コ N ，（γ ．） paratlela （R6ding ，1798）． Lanyang Hsi． イ ナ ズ マ カ ノ コ ガ イ （蘭陽渓産） ． Hsi ． ド ン グ U カ ノ コ ガ イ ロ N ，（V ．） plumbea Sowerby ， 1855 Lanyang （蘭 陽 渓産 ）

11 ロ N ．（Vittoida） variegata Lesson ，1830． Takangko ． ム ラ ク モ カ ノ コ ガ イ （大 港 口 産 ） ロ Septaria（Septaria） porcellana（Linnaeus．1758）． Takangko ． フ ネ ア マ ガ イ （大 港 口 産 ） ー ベ コ フ ・ 口 12． S．（Navicetla）lineata（Lamarck ，1816）．Takangko ． ッ ウ ネ ア ガ イ （大 港 産 ） ． Scale＝1mm ．

一 NII-ElectronicN 工 工 Eleotronlo LibraryLlbrary Service The malacologicalsocietymalacological society of Japan

172 VENUS: VoL 45, No.3(1986)

Remarks: Martens considered that NeritinQ faba Sowerby, N. avetlana

R6cluz and N. sotoerbiana Recluz are distinct species and that the latter two

are distributed in Taiwan. Furthermore, he regarded N. pulchetta Recluz as a

synonym of IV. sowerbiatna and N. interTupta Recluz as that of N. avellana. How-

ever, Tryon (1888) eonsidered that pulchetla, avellana and faba are all probable

synonyms of sozverbiana and that interrztpta pessesses all the characters of

N. nucleolus Morelet, 1857. Hirase (1934) applied Theodoxus (Ctithon) sower- bianus and T. (C.) faba to Japanese species, but Hirase and Taki (1954) identi- fied C. fthba with C. sowerbianu$. Thereafter, Japanese workers allocated

Japanese species into Clithon sowerbianus. On the other hand, Benthem Jutting (1956, 1963) used the names C. faba to Javanese species and C. sowerbianza to New Guinean one. Paee pointed out that the most commonly used name for

these snails was Ctithon so2verbianus (R/6cluz) and stated that for the sake of

stability it would be worthwhile to appeal to the International Commission en

Zoological Nomenclature to preserve this name. In examining the syntype speci-

mens of Neritina･ sowerbiana R/ecluz, 1842 (Museum d'Histoire Naturelle, Geneve and Museum National d'Histeire Naturelle, Paris) and N. faba Sowerby, 1836 (British Museum), the present author confirmed that these species were identi-

cal and considered it inadequate that Hirase and Taki used sozverbianus to

Japanese species. Therefore, Clithon faba (Sowerby) should be used for this

specles.

Pace assigned this species to the subgenus Vittoctithon by the characters

that the shell was covered by a smooth periostracum and the co]or pattern was quite variable. However, I consider it inadequate to use these characters as diagnoses of the subgenus and could not distinguish them from the subgenus Clithon s. str. by the shell, opercular and radular characters. Subgenus Pictoneritina Iredale, 1936. 4. (;lith{m (Pictoneritina) tht(m'astoma (Sowerby, 1833). (Fig. 4) Localities and habitats: Takangko, 3 specimens. On the boulders in the estuary but slight]y closer te the sea than the habitat of C. cerona. This species was originally described on the speeimens from Tahiti (Sowerby, 1833) and is known from Polynesia to Japan. It was newly reported from Taiwan and this speeies is eharacterized by two black radiating bands on the exterior of the operculum.

Genus Neritina Lamarek, 1816.

Subgenus Neripteron Lesson, 1830. 5. IVeritina (IVieripteron) aesricutata Lamarck, 1816. (Fig. 5) Localities a･nd habitats: Lanyang Hsi, 16 speeimens. On stones on the bank adjacent to the reed field of the estuary. This speeies was newly reported from Taiwan.

Subgenus Dost･ia Gray, 1840.

NII-Electronic Library Service The malacologicalsocietymalacological society of Japan

Komatsu: Freshwater Neritid Fauna in Taiwan. 173

6. IVIeritina (Dastia) violacect (Gmelin, 1791). (Fig. 6)

Localities and habitats: Lanyang Hsi, 2 specimens. Collected with N.

(2VeripteTon) auricutat-. This was a new locality in the northern Taiwan. Distribntion in Taizvan: Pingtung, Kaohsiung, Anping (Kurbda, 1941). Remarks: Pace (1973) allocated this species to the subgenus Neripteron,

sinee no explanatioll was given for the changes in taxonomic position by Kuroda

and Habe (1961), However, the subgenus Dostia is characterized by much

areuated shells and thieker opercula than in the subgenus Neripteron and trape-

zoid eentral teeth of radulae. Therefore, Dostia is aeeeptable as the subgenus of

the genus Neritina･.

Subgenus Vittina Baker, 1923.

7. IVeritina (Vittina) turrita (Gmelin, 1791). (Fig. 7) Locatities and habitats: Lanyang Hsi, 7 specimens. In the Teed field of the

estuary; on the mud, stalks of reed or stones on the bank, This species was

newly reported from [I]aiwan.

8. IVbritina (Vittina) paralteta (R6ding, 1798). (Fig, 8) Localities and habitats: Lanyang Hsi, 28 specimens, collected with N. (V.)

turrita. This species was newly reported from Taiwan.

9. IVbritina (V]ittina) plumbetz Sowerby 1855. (Fig. 9) t Localities and habitats: Lanyang Hsi, 28 specimens, collected with N.

CNeripteron) auricueata. Distribution in Taitv(mt: Aoti (Taipei Hsien) (Kuroda, 1941).

Subgenus Vittoida BakeT, 1923.

10. IVeritina (Vittoida) variegata Lesson, 1830. (Fig. 10)

Localities and habitats: Takangko, 1 specimen. On the muddy bed of the

bank. This is a new loeality in the central Taiwan.

Distribution in Taiwan: Kaohsiung (Kuroda, 1941).

Remarks: As well as the subgenus Dostia, Pace did not aecepted Vittoida

as the subgenus of the genus Neritina. However, I admitted a differentiation

of Vittoida from Vittina in the shell, opercular and radular eharacters. Thus,

I alloeate .this species under the subgenus 7ittoida,

Genus Septaria Ferussae, 1807.

Subgenus Septaria s. str.

11. Septaria (Septaria) poraellana (Linnaeus, 1758). (Fig. 11) Locatities ana habitats: Takangko, 32 specimens; Tachia Hsi, 29 specimens,

collected on stones with Clithon corona. The latter locality was a new one in

the central Taiwan.

Distribution in Taitvan: Hualien, Taitung, Kaohsiung, Pingtung (Hori-

kawa, 1935a, b); Santiaochiao, Takangko, Penghu Islands (Kuroda, 1941).

Remarics: Horikawa, Kuroda and Pace (1973) applied e'anetti Recluz to the Taiwanese species of Septaria, but I found that the type speeimens of ianelli

NII-Electronic Library Service The malacologicalsocietymalacological society ofJapanof Japan

174 vENUS: vol. 45, No,3(1986)

is no longer extant. In comparing the Taiwanese specimens with the Japanese

ones, I eould not detect any differences between these two lots in characters of

shell, operculum and radula. Therefore, I applied poTcellana Linnaeus, which

have been used for Japanese species, also to Taiwanese one.

Subgenus Navicetla Lamarck, 1816.

12. Septaria (2Vavioella) lineata (Lamarck, 1816). (Fig. 12)

Localities and habitats: Takangko, 12 specimens collected with Clithon

eorona on stones. This species was new}y reported from Taiwan.

Discussion

Freshwater and brackish water neritids of Taiwan represent 15 species,

including 12 species dealt with here: planospira in the genus NeTita; coTona,

retropictus, faba, oualaniensis and chlorostoma in the genus Clithon; pzttligera,

auriculata, violacea, turrita, paraltela, ptumbea and variegata in the genus Neri-

tina; porcehana and lineata in the genus Septaria. All of these species are also

distributed in Japan where three more species, Neritodryas subsulcata, N. dubia

and Septaria eumingiana, are distributed, There is a high zoogeographical aMnity

"No between Taiwan fauna and Japan one. According to Pace (1973), non-

marine neritids have been reported from the relatively straight coastline of

central western Taiwan in the region where the rift valley of the Formosan

Strait iB formed. This pattern also coTrelates well with that of the braekish

water thiarids of the subgenus Steno7netania, Neither of these primarily Indo-

Pacific groups appears to have penetrated the region which has relatively

recently been exposed to the sea...... ". Nevertheless, in this study, four species

were collected in the central-western Taiwan, even from only a single collection

site, where C. corona and S. porcetlana are abundant, As Pace has mentioned,

nearly all of the habitats of these animals are greatly infiuenced by human

population pressures of one sort or another. Neritids could not be collected in

rivers of the urban areas, but in the estuary with little influence of man's pres-

sures, existenee of considerab]e populations of neritids were confirmed. There-

fore, it can be expected that they may inhabit the similar environments ef the

central-western area.

The list of the freshwater and brackish water neritids in Taiwan.

("' Not collected in the present study)

es1. Nerita (Theliostyla) ptctnosptra Anton, 1839. 2. Clithon (Ctithon) eorona (Linnaeus, 1758). 3. C. (C.) retropictus (v. Martens, 1879). 4. C. (C.) faba (Sowerby, 1836). W5. C. (Pieteneritiua) oualaniensis (Lesson, 1830).

6. C. (P.) chlorostoona (Sowerby, 1833).

NII-Electronic Library Service The malaoologioalmalacological societysooiety of Japan

Komatsu ； Freshwater Neritid Fauna in Taiwan ， 175

ac7 ． Neritin〔z （Neritin α ） lmtligeT α （Linnaeus ， 1767 ）．

γ on auricul α α 8． N ，（Neripte ） t Lamarck ， 1816 ．

伽 viot α ce α 9． N ．（Pos ） （Gmelin ， 1791 ）．

10 ． N ．（Vittina） turritα （Gmelin ， 1791 ）．

11． ヱV ．（V ．） paT α lletα （R6ding ，1798 ）．

． ． ． α ． 12 N （V ） ptumbe Sowerby ， 1855 ’ vaT θ α 13 ． N ’ （Vittoida） i 9 α t Lesson ， 1830．

14 ． Sept α ri α （Sept α ria ） porcellα n α （Linnaeus ，1758 ）．

15 ， S ．（ヱVavicetlα ） lineα ta （Lamarck ，1816 ）．

Acknowledgements ’− Iwish to express my gratitude to Dr ． Philippe Bouchet （Museum

’ ， Paris ． National d Histoire Naturelle ， ）， Dr ．C1 Vaucher （Museum d Histoire Naturelle，

and Ms H Museum History London for loan Geneve ） ．K ． ．Way （British ，Natural ， ） the

of type specimens under their care ．

要 約

・ ・ 台 湾北 中 部 の 淡 水 汽 水 産 ア マ オ ブ ネ ガ イ 類 相 を 調 べ た 。 3 属 8 亜 属 12種 が 採 集 さ れ ， うち 5 種

こ に ア マ い は 台 湾新 記 録 で あ っ た 。 れ ら は 全 て 日 本 も分布 し，両 地 域 間 に は オ ブ ネ ガ イ 類 に 関 し て 高

動 物 地 理 学 的 類縁 性 が 示 され た 。

・ マ ブ ＊ 台湾 産淡 水 汽 水 棲 ア オ ネ ガ イ 類 目録 （ 本 研究 で は 採 集 さ れ な か っ た 種 ）

凱 Nerita （Theliostyla）Planospira Anton ，1839 ヒ ラ マ キ ア マ オ フ ネ ガ イ ー a34 Clithon （Clithon） corona （Linnaeus ，1758） イ ガ カ ／ コ ガ イ ー C ，〔C ，） retropictzas （v ． Martens ，1879） イ シ マ キ ガ イ

C ．（C ．） faba（Sowerby ，1836 ） カ ノ コ ガ イ

琢 C ．（Fictoneritina） oualaniensis （Lesson，1830） ヒ メ カ ノ コ ガ イ ハ α C ．（P ．） chlorostoma （Sowerby ，1833） ナ ガ ス ミ カ ノ コ ガ イ

繊 Neritina （Neritina） puJligera （Linnaeus，1767） カ バ ク チ カ ノ コ ガ イ コ ＆ N ．（NeriPteron ） 翩 7 記 κ 」α ’σ Lamarck ，1816 ツ パ サ カ ノ ガ イ

9n N ．（1）ostia ） violaeea （Gmelin ，1791） ヒ 卩 ク チ カ ノ コ ガ イ ー N ．（Vittina） turrita （Gmelin ，1791） シ 1 カ ノ コ ガ イ

ル 1＞．（V ．） Parallela（R6ding ，1798） イ ナ ズ マ カ ノ コ ガ イ

皿 N ．（V ．）plumbea Sowerby，1855 ド ソ グ リ カ ノ コ ガ イ ー B 1＞．（Vittoida） Variegata Lesson ，1830 ム ラ ク モ カ ．ノ コ ガ イ 蛙 Septaria （Septaria） porceUana （Linnaeus ，1758） フ ネ ア マ ガ イ

ベ コ フ ア マ E S．（Navicella ） lineata （Lamarck ，1816 ） ッ ウ ネ ガ イ

1」iterature eited

Benthem Jutting W ． S ， S ． Van ， i956． Systematic studies on the non −marine mollusca ， − of the Indo−Australian Archipelago． V ． Critical Revision of the Javanese Fresh ▼ f reubia 23 ： 259 −477 water Gastropods ． ， ． Benthem Jutting， W ． S ． S ． Van ．1963． Non −marine Mollusca of West New Guinea 。

Pt ．1 Mollusca and waters ． α Zoology 10 ： ， from fresh brackish Nova Guine ， ， 409 − 521 ．

species of mollusca and Broderip W ．J ．and Sowerby ， G ．B ．1833． Characters of new ，

一 NII-ElectronicN 工 工 Eleotronio Library Service The malacologicalsocietymalacological society ofJapanof Japan

176 VENUS: VoL 45, No.3(1986)

cenehifera eollected by Mr. Cuming. Pro. Cemm. Sci. Corresp. Zool. Soc. London,

1832: 194L202.

Habe, T. 1961. Colour Illustrations of the Shells of Japan. IL ix+ 182pp., 66pls.

Hoikusha (Osaka).

Hirase, S. 1934. A Collection of Japanese Shells with Illzastrations in Natural Colours.

14+217pp., 129pls. Matsumura Sanshodo (Tokyo).

Hirase, S. and Taki, Is. 1954. An Illustrated Handbook of Shellg in Natural Colours

from the Japanese Istancls and Adiacent Territory. xxiv+214pp., 134pls, Maru- zen (Tokyo).

Horikawa, Y. 1935a. A list of freshwater shells of Taiwan. Venus, 5: 26-33.

Horikawa, Y. 1935b. Distributions of freshwater shells of Taiwan. Trans. natur.

Hist. Soc. Taiwan, 25: 226-231.

Kuroda, T. 1941. A catalogue of molluscan shells from Taiwan (Formosa), with

deseriptions of new species. Mem. Fac. Sed. Agr., Taihoku Imp. Univ., 22: 65-216.

Martens, E. von 1879. Die Gattung Neritina. Conch, Cab., 2(10): 1-303, pls. 1-23.

Matsuda, E. 1924a. I. Taiwan no kai rui, umi-gai. Trans. nat?tr. Hist. Soc. Pormosa,

14: 1-40.

Matsuda, E. 1924b. II. Taiwan no kai rui mokuroku. Trans. natur. Hist. Soc. For-

mosa, 14: 41-59.

Pace, G. 1973. The Freshwater snails of Taiwan (Formosa). Malacol. Rev., 1973,

Suppl. 1: 1-108.

Tryon, G.W. 1888. Monograph of the families Neritidae, Neritopsidae, Adeorbiidae,

Cyclostrematidae, and Liotidae. Manual of Conchology. 10: 23-160, pls. 1-36.

NII-Electronic Library Service