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The taxonomic position of the Japanese mountain mole (Euroscaptor mizura) was reassessed based on its external and skeletal morphologies. The muzzle shape of the intact individuals in this species exhibits a unique central groove on the ventral side, widening into a small naked portion at the tip. The naked portion becomes long and triangular in dried skin specimens, which was previously used as a specific characteristic of this species. It has the longest tail of talpine moles, with a rod shape that becomes narrow and lanceolate-shaped at the tip. The auditory ossicles include the malleus with a constricted neck and incus with a long processus brevis. It has a regressive mogeroid-type pelvis with two sciatic foramina, and a sacrum fused to the ischium. These morphological characteristics are not shared with continental Euroscaptor species, with which the Japanese mountain mole was originally classified based on the dental formula. Therefore, a new genus is proposed for this species.

The chromosomal relationships between the Japanese water shrew Chimarrogale platycephalus and the Eurasian water shrew Neomys fodiens were investigated by conventional and differential staining. From the side-by-side analysis of matching G-banding patterns from the two species, a high degree of G-band homology was recognized in most of the chromosomes that were compared, although the extent of such homology was unclear in several small chromosomes. In C. platycephalus, large blocks of C-heterochromatin (C-blocks) were found in pair nos. M1, M8, M10 and ST23 and in the Y chromosome as conspicuous C-bands, while N. fodiens had no such C-blocks, having centromeric C-bands on most chromosomes with the exception of several small pairs, which included ST1 and ST23. Silver-stained nucleolus organizers (Ag-NORs) were found only on the secondary constriction of pair no. 1 in C. platycephalus and on the minute short arms of ST23 and ST24 in N. fodiens. A discussion of interspecific differences in C-bandin...

The patterns of morphometric variation in skulls among different species and among intraspecies geographic populations, of five taxa (four species and one subspecies) of the mole genus Euroscaptor from Vietnam were investigated. Univariate and multivariate analyses were conducted based on 16 measurements of 140 specimens. Four groups based on skull size and shape were identified: 1. E. kuznetsovi + E. orlovi, 2. E. subanura, 3. E. parvidens ngoclinhensis, and 4. E. p. parvidens. Euroscaptor p. parvidens and E. p. ngoclinhensis clearly differed in overall size, proportions, and allometry trends. Therefore, E. p. parvidens and E. p. ngoclinhensis likely represent distinct species. Our analysis also revealed remarkable interspecies and geographic variations in 18 Vietnamese populations of studied taxa. Based on morphological divergence patterns, previous molecular evidence, and data on geographic distribution, we discuss the importance of geographical isolation caused by rivers, mountains, and altitudinal distribution.

Forefoot characteristics of the Ryukyu long-furred rat, Diplothrix legata, in the Amami-oshima, Tokunoshima, and Okinawajima Islands of the southern part of Japan (the Nansei Archipelago), were analyzed morphologically considering its arboreal lifestyle. The presence of a nail on the pollex was confirmed and seemed to be regarded as an arboreal feature, based on the presence of nails in other arboreal murids reported in previous studies. In addition, a linear palmar groove was confirmed between the interdigital pads and the thenar-hypothenar pads. We tried to allow the forefoot to take hold of a thin stick at this groove; the stick fit well in the groove, and it seemed to be possible to grip by the fingers except for pollex. Thus, the sizes and positions of palmar swollen pads forming the linear groove were considered to be useful for gripping a thin twig in an arboreal lifestyle. In addition, the entire unguis size tended to be larger in Okinawajima Island than in Amami-oshima Island as a geographical variation.

Skull morphological characters are used for species and subspecies identification in the manatees, but no comparative study has investigated skull growth. We examined progressive ossification in the cranial sutures of 251 skulls of West Indian manatees, 19 skulls of African manatees and 17 skulls of Amazonian manatees. Degrees of cranial suture fusion were evaluated based on gross observations of skull specimens. Our results suggest that ossification patterns in occipital region sutures follow a fixed sequence in living manatees. In all manatees, the suture between the sphenoid and occipital bones fused first, while the supraoccipital-exoccipital synchondrosis fused last. The ossification sequence observed in manatees was not found in descriptions of other mammals, including the dugong. We concluded that this ossification sequence is a unique, common character of living manatees. We also found two differences in the sequence of occipital region development in two subspecies of the West Indian ma...

The brachial plexus of the okapi showed the evolutionarily intermediate status between the underived ruminants and the giraffe with elongated neck. Whereas the C6 was the thinnest among the roots of the brachial plexus, the C7, C8 and T1 were much thicker in the okapi. From the data we concluded that the okapi was equipped with the intermediate characteristics of the disappearing C6. Although the nerve of the C6 should be elongated in accordance with the long neck in the Giraffidae, the extraordinary elongation of the C6 may have no advantages in the function of the innervations. In the okapi, therefore, we suggest that the function of the C6 has been mainly replaced with that of C7.

The presacral vertebra of anteaters was examined by three-dimensional CT image analysis of the xenarthrous processes peculiar to the Order Xenarthra. The anteater is equipped with two following articulations in addition to the normal zygapophysial articulation. The dorsal xenarthrous process of the former vertebra articulates to the ventral area of the base of the mammillary process in the later vertebra. The pocket-like structure in the ventral area of the mammillary process receives the dorsal and ventral xenarthrous processes of the former vertebra. The complicated articulations do not obstruct the ability of the giant anteater to flex dorsally and laterally, however aids flexibility and strengthens the caudal thoracic and lumber regions of the animal. The xenarthrous processes and articulations may function as a supporter of the body weight during the bipedal standing posture when the anteater destroys the nests of ants and termites and protects itself from the enemies.

We present the first karyological study on Kloss's mole Euroscaptor klossi from Chiang Rai Province of Thailand. We used differential chromosome staining methods and determined the diploid and fundamental autosomal numbers to be 36 and 54, respectively. Compared with the G- and C-banded karyotypes of the Japanese mountain mole E. mizura, the karyotype of E. klossi involved a reciprocal translocation followed by a pericentric inversion of chromosomes 1 and 16 of the ancestral karyotype of E. mizura. Some minor C-band duplications supplemented the karyological differences between the two species. The karyotype of E. klossi is distinct from that of the Malaysian mole E. micrura malayana examined previously and these species have distinct scenarios in diverging from the ancestral karyotype of the genus Euroscaptor.

The taxonomy of the East Asian moles of genera Euroscaptor, Parascaptor and Scaptochirus, distributing in the Himalayas to China were controversial both in the generic and specific levels. These genera were named as more than ten species since the beginning of the description by Brian Houghton Hodgson in 1841. Several explorers had the expedition to this area and brought the specimens of these moles to European and American Museums and named them. One of the purpose of this paper is to review the historical note on the discoveries of Asian mole species as the compass to situate the taxonomic problem of these moles. As a matter of taxonomic evaluation, the problem of the usage of dental formula as the generic diagnosis is discussed in the reference of the examples of recent taxonomic works. Distribution of these East Asian talpids are scattered in the mountain regions like plot according from the collecting records by museums. Current museum collections are not enough to examine their local and in...

We report the first karyological description of a southeast Asian mole, the Malaysian mole (Euroscaptor micrura malayana). The karyotype of the Malaysian mole includes 36 chromosomes, which consist of 18 biarmed and 16 acrocentric autosomes and the sex pair. The sex chromosomes are a small meta-submetacentric X chromosome and a minute dot-like Y chromosome, although the latter is somewhat larger than that of some talpid allies. Autosomal complements include one pair of NOR-bearing chromosomes. A comparative G-banding analysis with the Japanese congener E. mizura showed that these two species share high G-banding homology, and their differences on two pairs of chromosomes are explained by a single reciprocal translocation. The karyological similarity of these distant geographic species is discussed in a systematic and evolutionary context, based on comparisons to other species distributed between them.

1 Laboratory of Animal Management and Resources, Graduate School of Bio-Agricultural Sciences, Nagoya University, Nagoya, Aichi 464-8601, Japan 2 Experimental Animal Center, Miyazaki Medical College, Miyazaki 889-1692, Japan 3 Wildlife Ecology Laboratory, Forestry and Forest Products Research Institute, Tsukuba, Ibaraki 305-8687, Japan 4 Department of Wildlife and National Parks 43200 Kuala Lumpur, Malaysia

The upper dental formula of the Russian desman Desmana moschata (Linnaeus, 1758) (Insectivora, Talpidae) is considered based on the position of the premaxillary suture (sutura incisiva). From the lateral aspect, this suture extends to the second tooth in the tooth row. From the ventral aspect, the suture connects the common alveolus fossa of the second and third teeth in front of the second tooth on the labial edge and behind it on the lingual edge; consequently, the third tooth in the upper row appears to be derived from the maxilla. Therefore, the upper tooth formula of D. moschata may differ from the traditional fundamental dental formula of eutherian mammals (I3, C1, P4, M3), and consist of two incisors, one canine, five premolars, and three molars (I2, C1, P5, M3). This hypothetical view, however, assumes two changes, a tooth deletion in the incisor row and an addition in the premolar row. The significance of the premaxillary suture and possible pitfalls in using it to define dental formulae are discussed.