An introduction to the Japanese groundwater animals with reference to their ecology and hygienic significance

Abstract

In the first half of this century, little was known of the groundwater animals of Japan. In 1916, Prof. Ijima and Dr. Kaburaki gave a description of a hypogean planarian as the first groundwater animal of Japan. Following this description, eleven species were recorded from wells and caves during the thirty-five years up to 1950. Thus, only twelve species of animals were registered as groundwater animals of Japan in the first four decades of this century. Since 1950, a number of groundwater animals have been collected and described from caves and wells of Japan, and the present list of the troglobites from the groundwaters of Japan comprises almost two hundred species which are classified in eight phyla, thirteen classes, eighteen orders, forty-seven families, and at least seventy-seven genera. However, numerous specimens of Oligochaeta, Ostracoda, Cyclopoida, and particularly those of microorganisms such as Protozoa, Hydra, Nematoda, and Rotatoria, etc. still remain undescribed. Because sufficient numbers of mature specimens in satisfactory condition are not available for study, some material of Nemertinea, Archiannelida, Turbellaria, Dytiscidae, Phreatodytidae, etc. are also left undescribed. In recent years, a remarkable decrease in the number of wells available for the collection of material has forced some speleobiologists to divert their activities to the field of the interstitial fauna of rivers and seashores. Besides the troglobites listed in Table I, various groups of troglophiles and trogloxenes have been obtained from the ground waters of Japan. Some of them are significant as a biological indicator of well-water pollution upon which I shall comment later on. Among the aquatic troglobites of Japan, one of the noteworthy groups may

The subterranean amphipod crustacean fauna of an artesian well in Texas

“…At present the genus Bogidiella is composed of 28 described species and several provisionally recognized species (Ruffo, 1973;Dancau, 1973b;Ruffo and Vigna Taglianti, 1973Ruffo and Schiecke, 1976;Matsumoto, 1976;Stock, 1978 DIAGNOSIS.-A small, slender-bodied subterranean species distinguished by the characters of the genus. Largest specimens (males ?…”

A cave leech (Hirudinea, Erpobdellidae) from Croatia with unique morphological features

“…Most of the specialized aquatic cave leeches belong to the family Erpobdellidae. They have been recorded from Japan (Matsumoto 1976; not taxonomically studied), France (Turquin 1994), northern Italy, the Dinaric karst of west Croatia (both B. Sket, unpublished data), the Dinaric karst of Hercegovina, Dalmatia and Montenegro, Georgia, Turkey and Texas, USA (Sket 1986). The only exception known is the gnathobdellid Haemopis caeca Manoleli, Sarbu & Klemm, 1998, recorded from an ecologically exceptional cave in Romania (Sarbu & Kane 1995).…”

First record of subterranean rissoidean gastropod assemblages in Southeast Asia (Mollusca, Gastropoda, Pomatiopsidae)

“…Species inhabiting similar habitats were mainly known only from North and South America, North Africa, Europe and the Balkans through Turkey and the Caucasus to Central Asia (Bole andVelkovrh 1986, Kabat andHershler 1993). The localities from Laos are situated between the single so far known locality in Sri Lanka (wells in the village of Pokonwita, south of Horana) and the few localities hitherto known throughout the Japanese Archipelago (Mori 1938;Kuroda and Habe 1957;Habe 1965;Kuroda 1963;Matsumoto 1976;Bole and Velkovrh 1986). The new finds partly fill the zoogeographical gap and also suggest their probable presence in a much wider area than hitherto supposed: from Naga Hills and Arunachal-Pradesh in India through Myanmar, Thailand, Laos and Vietnam to South China (YunNan and GuangXi) and likely northward to the central and east mainland of China and Korea.…”