The distributions of two camptandriid crabs,Deiratonotus cristatus and D.japonicus,were studied on the basis of 380 specimens collected in 2004 and 2005,from the brackish waters in Kochi Prefecture,Japan.The former species was abundant on intertidal sandy-mud bottoms of the innermost part of Urado Estuary and water pools formed during the ebb tides near the mouth of the Niyodo River. Specimens of D.japonicus were frequently collected from pebbly bottoms in the rivers from eastern to western Kochi Prefecture. Although many localities for these species were confirmed than previous studies,their habitats seemed to be easily affected by various human activities.
Stomato pod crustaceans of the genus Harpiosquilla in the family Squillidae were studied on the basis of 141 specimens collected by bottom trawlers from Tosa Bay.The following four species were recognized:H.harpax(de Haan,1844),H.annandalei(Kemp,1911),H.melanoura Manning,1968,and H.sinensis Liu et Wang,1998.In the Japanese fauna,H.melanoura has been represented only by two specimens ,the first from Kochi Prefecture and the second from Osaka Bay,but 12 additional specimens were collected during this study.Harpiosquilla sinensis frequently collected at Saga fish market(33°04′18″N,133°06′55″E)is reported for the first time in Japanese waters.
Bulletin of the Shikoku Institute of Natural History NO.3

四国自然史科学研究第3号 要旨
A brackish water potamidid snail Cerithidea cingulata was studied in Uranouchi Inlet and Susaki Bay.In 2000,this species was designated as one of the critically endangered species of Kochi Prefecture.Prior to this study,living individuals of C.cingulata were observed in 1981 on the intertidal sandy-mud flats in Uranouchi Inlet,known to be the only locality for living snails in Kochi Prefecture,according to a report in 2002.However ,the species seemed to be extinct,because the living snails have not been seen after 1981.This study confirmed the occurrence of C.cingulata at two localities,Shimo-nakayama and Lpngauchi,both in Uranouchi Inlet in 2005.In addition,a dead-shell of C.cingulata was obtained from Susaki Bay in 2005,where no living or fossil records of this species have been reported.
Avifauna and vegetation were studied in the Kuroson Natural Observation Forest,Kochi Prefecture.A survey stand was set in the old-growth natural forest in warm-temperate zone where 640-700m above sea level was.A total of 25 bird species,including 19 in the summer and 16 in the winter,were recorded in the stand.Frequently observed birds were Parus major(great tit),Troglodytes troglodytes (wren),Sphenurus sieboldii(Japanese green pigeon) and Cyanoptila cyanomelana (blue-and0white flycatcher)in the summer,While Fringilla montifreingilla (brambling),Hypsipetes amaurotis (brown-eared bul bul),T.troglodytes and Parus ater(coal tit)in the winter.Dominant woody plants with a large basal area were Qurcus salicina,Carpinus laxiflora and Acer mono var.ambiguum.
The distribution of two sympatric crabs of the genus Ptychognathus,P.ishii and P.capillidigitatus,occurring estuarine environments in Kochi Prefecture studied from December 2004 to October 2005.Previously known localities for P.ishii and P.capillidigitatus in Kochi Prefecture were 12 and five,respectively.This study confirmed 18 and 12 new localities for each species .These two crabs were common in estuarine environments from central to western Kochi Prefecture.Their occurrence could not be confirmed in rivers where its mouth frequently closed by wave actions,and in rivers where its bed and banks protected artificially.
Crabs inhabiting brackish rivers and estuaries on the southern coast of Tokushima Prefecture were studied on the basis of 169 specimens collected in August and October 2005.The occurrences of 24 species belonging to 19 genera in 5 families were recognized.The following species seemed to be zoogeographically important :Halicarcinus coralicola,Neorhynchoplax okinawaensis,Uca lactea,Acmaeopleura parvula,Ptychognathus capillidigitatus and P.ishii, Chasmagnathus convexus,Helice sp.Nanosesarma gordoni and Parasesarma acis.
The distribution of Nanosesarma minutum was studied on the basis of 336 specimens collected in 2004 and 2005.This study showed that N.minutum commonly occurred among bivalves and holdfasts of seaweeds attached to the substrata in estuarine environments on the coasts of central Kochi Prefecture.
The occurrence of gobies (Family Gobiidae)in the southern region of Urado Estuary in Kochi City was studied from April 2004 to January 2005.A total of 27 species belonging to 22 genera were recorded.Acanthogobius lactipes(endangered species of Kochi Prefecture),Apocryptodon punctatus(vulnerable species),two near endangered species Drombus sp.and Pseudogobius masago,and Bathygobius hongkongensis were first obtained from Urado Estuary.Specimens of Psammogobius biocellatus and Oxyurichthys ophthalmonema represented the second record for each species of Kochi Prefecture were also confirmed:Callogobius tanegasimae,Eutaeniichthys gilli,Periophthalmus modestus and Taenioides cirratus.These facts strongly suggested that Urado Estuary is one of the important brackish water environments in Kochi Prefecture.
Fishes from the Shinbori River in central Kochi City were studied.Nine specimens confirmed the occurrence of Lates japonicus,one of the critically endangered fishes of Kochi Prefecture.Four specimens of Eleotris oxycephala designated as one of the near endangered fishes of Kochi Prefecture were collected.In addition,a pipefish Hippichthys(Hippichthys)heptagonus was first recorded from Kochi Prefecture,representing the northernmost record of this species.The occurrence of L.japonicus and pipefishes seemed to be closely related with Zostera japonica growing on the riverbed.
Roost usage during the hibernation by cave-dwelling bats was studied in Kochi Prefecture from 2003 to 2005.The following four species were found from the roosts : Rhinolophus ferrumequinum,Rhinolophus cornutus,Myotis macrodactylus and Miniopterus fuliginosus.The number of roosts used by bats was highest in R.ferrumequinum,though R.cornutus was most abundant among the four species.Although the hibernation colony of M,fuliginosus in the Ryugado cave had been reported,the occurrence of this colony was not confirmed in the present study.
We investigated the vegetation and flora of Naruyama area,Ino Town,a typical rural mountainous area in Kochi Prefecture.We listed 117 families and 567 species (including subspecies and variety)in the area of 2.2ku.They consist of 73 spp.belonging to Pteridophyta,6 spp.Gymnospermae,and 488 spp. Angiospermae which include 13 endangered species and 29 alien species.The alien species rate of this area was very low(5%)as compared with those of other areas. The differences in floristic composition and species diversity among community types were discussed based on 188 vegetation data collected from sample satands of seven forest types and many types of scruds and herbaceous communities developing on roadside slopes and abandoned terraced paddly fields.The values of species diversity indices of slope stands maintained by frequent mowing around roads and paddy fields were very high,while those of abandoned terraced paddy fields were relativery low.The beta diversity between communities in Naruyama area was high,because various human disturbances such as cutting,mowing,clearing,plowing and burning,provided a variety of habitats for plants.In addition,serpentine areas which have particular vegetation and flora,contributed to increase the plant species diversity of Naruyama area.However,the increase of abandonment of arable fields and vegetation succession following after that has reduced the plant species diversity of this area.
佐久間智子・山城沙織・森口弥生・石川慎吾・三宅 尚