New Stygiotrechus (Coleoptera, Trechinae) from Non-calcareous Areas
|Three new trechine beetles belonging to the genus Stygiotrechus are described from Gonji-ana Cave/Mine at the western side of the Kii Peninsula, Zozu-san in northeastern Shikoku, and Ponpon-yama to the west-southwest of Kyoto, respectively. The first locality is a sandstone cave artificially modified for the purpose of mercury mining, while the other two are low hills covered with temperate broadleaved trees. The Gonji-ana form, named S. nishikawai, is a new species closely related to S. ohtanii; the Zozu-san form, which is endogean, is regarded as a new geographical race of S. satoui, and the Ponpon-yama one, also endogean, as that of S. morimotoi. The occurrence of S. nishikawai in a cave/mine in the Hidaka-gawa drainage is of special interest from the zoogeographic point of view, since the locality is in an area near to the Pacific coast, far south beyond the Median Tectonic Zone of Japan.|
|A new eyeless species of trechine beetle is describcd for the first time from the Nepal Himalaya. It belongs to a new genus, which seems to take part in the Aphaenops group but differs from all the genera previously known in the peculiarities of protibiae and aedeagal apex. A new name, Himalaphaenops nishikawai, is given for this remarkable species. Its discovery in an endogean habitat at a high altitude will open up a new prospect that an interesting cave fauna may exist in the Himalayas and Southwest China.|
Two New Lathrobium (Coleoptera, Staphylinidae) Found in Limestone Caves of Japan
|Two new staphylinid beetles belonging to the genus Lathrobium are described and illustrated. One of them, L. uenoi, was found in Shizushi-do Cave in Kyoto Prefecture, while the other, L. yozawanum, was taken in Yozawa-do Cave in Tokyo Prefecture, both in Central Japan.|
Occurrence of a New Sinostemmiulus (Diplopoda, Nema-somatidae) in a Limestone Cave of Southwest Japan
|The milliped genus Sinostemmiulus, originally erected as a member of Stemmiulidae but later transferred to Nemasomatidae, has been known until now from only a single Chinese species. Recently, a milliped apparently belonging to this genus was discovered in a limestone cave of West Japan. It differs from the type-species in the details of male gonopods and is doubtless new to science. It is described in this paper under the name of S. japonicus.|
A New Spider, Nesticus shureiensis (Araneae, Nesticidae) from Mie Prefecture, Central Japan
|A new spider, Nesticus shureiensis, from Shurei-no-mizu-ana Cave (Mie Prefecture, Japan) is described. This species belongs to a long-legged and eastern Japanese type nesticid. Together with the previously described species, N. suzuka, N. gujoensis and N. masudai, this species forms a species-group, which has no distinct connection with the neighboring groups.|
A New Coelotes (Araneae, Agelenidae) from Central Japan
|A new agelenid spider, Coelotes tumidivulva, is described from Central Japan. It is easily distinguished from all the known species of the genus by having very small anterior median eyes and a large protruded epigynum. The spider seems primarily endogean, but has also been found in an abandoned adit of a manganese mine located at the southwestern part of the Suzuka Mountains in Shiga Prefecture.|
Two New Macrochelid Mites (Gamasida) Found in Mine Adits of Japan
|Two new species of gamasoid mites belonging to the family Macrochelidae are described from abandoned mine adits in Southwest Japan, under the names of Macrocheles (Macrholaspis) ovoideus sp. nov. and M. subterraneus sp. nov. This is the first record of macrochelid mites from the subterranean domain of Japan.|
|Yoshinari KAWAMURA and
Keiichi KAJIURA Kamo
Mammalian Fossils from Sugi-ana Cave, Gifu Prefecture, Central Japan
Mammalian fossils obtained from Sugi-ana Cave are treated in this report. The cave is situated in Hachiman-cho, Gifu Prefecture, Central Japan (long., 136'59'E;lat.,35'44'N). It is a narrow and steeply inclined limestone cave. Mammalian fossils were found from the sediments of the cave floor near the entrance. The sediments are probably redeposited here, so that they contain several fossil bones together with bones of the recent. The fossil bones are, however, rather easily distinguished from the recent ones by the degree of their fossilization and preservation . The characteristics of the fossil assemblage are summarized as follows :
1 ) Among the fossil assemblage, nineteen forms of mammals are recognized, most of which are micro-mammals. Of these, two are extinct and one is exotic to the Japanese Islands except Hokkaido, but others are all extant. Two living forms, Dymecodon pilirostris TRUE and Eothenomys sp. are predominant in the number of remains.
2) In the assemblage, insectivores are abundant in number and variety. It is peculiar that the insectivore forms sporadically distributed only on high mountains at present are associated with those which are widely distributed in lowlands. In addition, it is also interesting that an extinct Japanese burrowing shrew, Anourosorex japonicus SHIKAMA et HASEGAWA is included.
3) The forms which are assigned to Chiroptera, Primates and Lagomorpha are relatively few in number, and all of them are living forms.
4) In rodents, microtines are most abundant. Among them, Clethrionomys sp. is considered to be an exotic form which is not distributed in present Honshu, and Microtus epiratticeps YOUNG is an extinct form which was first described from Choukoutien Locality 1. In numbers of microtine molar M1 obtained, the proportion of exotic and extinct ones attains to 7%.Compared with other assemblages of the Quaternary fossil localities in Japan, the fossil assemblage of Sugi-ana Cave has similar content to those of the Upper Kuzuu Formation and its correlatives. Though there are some stratigraphical problems to be solved as to the origin of those fossiliferous cave sediments, the fossil assemblage treated here is assumed to be the Late Pleistocene in age. The materials of the extinct and exotic mammals such as Anourosorex japonicus, Clethrionomys sp. and Microtus epiratticeps are described.
|Yoshikazu HASEGAWA and
A Common Otter Remain from Taka-ga-ana Cave of the Akiyoshi-dai Karstic Plateau. Yamaguchi Prefecture, Japan
The karstic plateau of Akiyoshi-dai, Yamaguchi Prefecture, South-west Japan, is divided into two areas, Higashi-dai (east plateau) and Nishi-dai (west plateau). On the northeastern slope in the northern central part of Nishi-dai is found Takaga-ana Cave. The elevation of the cave entrance is 241 m above sea-level. Since 1973, the junior author, NAKAGAWA, and his coworkers have repeatedly investigated the cave, and have revealed that the cave is relatively large and considerab]y complex in structure, with a total extension of 4.5 km and a relative relief as large as 156 m. The cave sediment spreading from the entrance down to the bottom contains fairly abundant remains of vertebrates comprising 30 species, more than 20 of which are Mammalia. Especially the remains of the Japanese monkey (Macaca) consist of ten or more individuals, comparable to the Macaca assemblage in Ojika-do Cave at the Hirao-dai Karst, Kitakyushu City (HASEGAWA et al. , 1968). Most of the remains were obtained by surface collection and were identified with living species. They included a skeleton of a dog which had apparently fallen into the cave and died quite recently. The sediment near the cave entrance was excavated down to a clay bed at a depth of several tens of centimetres from the surface, and in this clay bed were found fragments of an elephant vertebra. The sediment must be of the Pleistocene to the Recent Age. The otter reported herein was collected from the Kawauso Branch of the main central cave. This branch passage is a slender crack-Iike shaft. The otter was found buried in red soil on the middle terrace of a pothole shape, 16 m above the channel leading to the main cave. It is thinly coated with travertine. It is not clear how and when the otter came into the cave, but it is probable that the upper end of the Kawauso Branch was open onto the surface, through which the otter might have entered the cave.
Although the present distribution of the Japanese otter is restricted within the Shikoku region, it was widespread all over Japan during the Jomon Period at least. Subsequently, the number of individuals has decreased rapidly and now the otter is on the way to extinction. The occurrence of the otter remains in Taka-ga-ana Cave is the first record in the Akiyoshi district, and proves that the otter was once distributed also in this district. From the fact that the fossilization of the specimen is not much advanced and its morphological features do not differ from those of the living species, it is suggested that the otter inhabited this district until rather recently.
Development of Limestone Caves and the Groundwater Paleoenvironment in the Akiyoshi-dai (Plateau), Japan - With an Example in the Kazaana-dai Area -
Based on the investigation of the solutional features and frameworks of the caves in the Kazaana-dai area, southern Akiyoshi Plateau, the cave development of the area is preliminarily dealt with, with special reference to the groundwater paleoenvironment. Formative cave levels in the Akiyoshi Plateau may be classified as follows (Fig. 3) :
1. Upper horizontal caves : 260-300 m above sea-level
Upper vertical caves : 290-340 m above sea-level
2. Middle horizontal caves : 150-200 m above sea-level
Middle vertical caves : 210-250 m above sea-level
3. Lower horizontal caves : 90-140 m above sea-Ievel
Lower vertical caves: 120-200 m above sea-level
Two phreatic cave frameworks are recognized at altitudes of 150-230 m (P1) and l00-160m (P2), respectively. The first base level to P1 is estimated at 260-280 m from the evidence of developmental frequency of horizontal caves shown in Fig. 3. That level is correlative with the Chohjagamori land-surface in the early to middle Pleistocene. The second base level to P2 remains at 160-200 m on the basis of the solutional features of water-tab]e zone. It is correlative with the Wakatakebara land-surface in the middle Pleistocene. The development of caves in the southern Akiyoshi Plateau may be inferred as follows (Fig. l0).
First stage : The first base level (BL1) was at 260-280 m and the contemporaneous phreatic cave systems were formed at 150-230 m above sea-Ievel.
Second stage : The second base level (BL2) formed at 160-200 m and some caves expanded as water-tab]e passage at that height. Phreatic cave systems were newly developed at 100-160 m above sea-level.Third stage: The base level lowered to about 100 m above sea-level. Many complex caves were completed to integrate the phreatic passages and the water-table passages developed in pre-stages. Such water-table caves as Akiyoshi-do were vigorously formed.