Phylogenetic relationships of four species of floating gobies (Gymnogobius) as inferred from partial mitochondrial cytochrome b gene sequences

 To clarify the intra- and interspecific relationships of four Gymnogobius species, G. urotaenia, G. isaza, Gymnogobius sp. 1 (sumiukigori), and Gymnogobius sp. 2 (shimaukigori), partial mitochondrial cytochrome b gene sequences of 639 bp were obtained for a total of 31 specimens from Japan and Korea, plus 2 outgroup specimens. Twenty-nine haplotypes were identified in the ingroup, with a total of 122 variable sites (19.1%). The individuals regarded as the same species morphologically were monophyletic genetically. Sequence differences between amphidromous individuals of three species distributed in both Japan and Korea were relatively small (0.16–1.25%). The largest intraspecific sequence difference was observed between individuals of G. urotaenia from Lake Biwa and those from other localities (1.25–2.19%). Interspecific sequence differences ranged from 4.07% to 13.46%; neighbor-joining, maximum-parsimony, and maximum-likelihood methods indicated that Gymnogobius sp. 2 diverged first, followed by G. isaza, with Gymnogobius sp. 1 and G. urotaenia being monophyletic. The estimated divergence time of each species, based on estimated divergence rates for mitochondrial protein-coding genes already reported (0.8–2.8%/my), suggested that speciation occurred mainly in the Pliocene (possibly Miocene), with G. isaza (a Lake Biwa endemic) diverging significantly earlier (probably Lake Kouga stage) than estimated in previous studies. In contrast, according to the previous hypothesis, the substitution rates were highly overestimated to about 12–20%/my. Received: November 19, 2001 / Revised: May 20, 2002 / Accepted: June 18, 2002 Acknowledgments Special thanks are due to Katsutoshi Watanabe and Yuji Yamazaki for valuable advice and providing fish samples. We also thank Kouji Nakayama, Toshiyuki Ohkawa, Motoomi Yamaguchi, and members of the Laboratory of Marine Biology, Fukui Prefectural University, and members of the Laboratory of Molecular Marine Biology, Ocean Research Institute, University of Tokyo, and the Laboratory of Marine Stock Enhancement, University of Kyoto, for their help and advice during the present study. Correspondence to:Shigeo Harada     

<Emphasis Type="Italic">Zacco sieboldii</Emphasis>, a species distinct from <Emphasis Type="Italic">Zacco temminckii</Emphasis> (Cyprinidae)

 Two biological types of Japanese dark chub, so-called types A and B of Zacco temminckii, were taxonomically inspected. A comparison of types A and B with the lectotypes of Leuciscus sieboldii and L. temminckii in Siebold's collection revealed that type A is identical to L. sieboldii, whereas type B matches L. temminckii. Hence, Zacco sieboldii and Z. temminckii were redescribed on the basis of the lectotype and additional specimens from Japan. Zacco sieboldii is distinguishable from Z. temminckii by having a narrower band on the anterior portion of both body sides, nine branched rays of anal fin (10 in Z. temminckii), lateral line scales not less than 53 (not more than 52 in Z. temminckii), and scales above lateral line not less than 13 (not more than 11 in Z. temmincki). A key to the species of Japanese Zacco is also provided. Received: August 15, 1999 / Revised: July 25, 2002 / Accepted: August 19, 2002 Acknowledgments We express our cordial thanks to all the following investigators: Dr. M.J.P. Van Oijen (RMNH) for the specimen loan of von Siebold's collection; Professor San-Rin Jeon, Sang-Myung University (formerly, Seoul) for providing several papers on Korean Zacco congeners; Dr. Harumi Sakai, National Fisheries University; Dr. Tetsuo Furukawa-Tanaka, Museum of Nature and Human Activities, Hyogo; Dr. Seishi Kimura, Mie University; Dr. Akihisa Iwata, Kyoto University; Dr. Osamu Katano, National Research Institute of Fisheries Sciences; Mr. Kazuo Hoshino, Oita Marine Palace; and Dr. Kouichi Kawamura, National Research Institute of Aquaculture, for the valuable comments and information on the ecological aspects of both species of the Japanese dark chub. Correspondence to:Kazumi Hosoya     

A fluvial population of Cottus pollux (middle-egg type) from the Honmyo River, Kyushu Island, Japan

 Specimens of the Cottus pollux species' group collected from the upper part of the Honmyo River, Nagasaki Prefecture, Japan, were subjected to morphological and allozyme analyses to place them into one of the recognized valid taxa, viz. small-egg type (SE type), middle-egg type (ME type), or large-egg type (LE type). They were identified as ME type on the basis of specific morphological characteristics, such as laterally depressed cross-sectional shape at posterior half of the body and deep caudal peduncle, and by having a diagnostic allozyme allele (MEP ^* 54). This ME-type population is the first recorded from Kyushu Island, Japan. An ecological survey of the population revealed that females spawned larger eggs (2.8–3.2 mm in diameter) than those of other amphidromous populations, from which well-developed yolk-sac larvae of about 8.0 mm TL were hatched out. In addition, ME-type specimens collected on 25 and 26 May 2001 included 15 sex-unknown juveniles ranging from 18.8 to 30.2 mm SL, suggesting that they represented larvae hatched out on a nearby spawning ground, with no experience of downstream migration into Isahaya Bay. This observation strongly suggests that the ME-type population in the Honmyo River has a fluvial lifestyle, being different from other amphidromous populations. The former population may have arisen from an amphidromous ancestor through changes in egg size and early ontogenetic development. Received: February 25, 2002 / Revised: May 21, 2002 / Accepted: June 17, 2002 Acknowledgments We thank Professor M. Azuma, Nagasaki University, for his kind guidance of our field survey in the Honmyo River and Dr. G.S. Hardy, Thames, New Zealand, for correcting the English. Thanks are also offered to Mrs. Y. Miyajima and Y. Masaoka, Kyushu Branch of Construction and Technology Institute Co., for their helpful cooperation in the field survey. Drs. H. Sakai, National Fisheries University and Y. Yamazaki, Toyama University, and Mrs. N. Okabe and Y. Suzuki of Yamagata Prefecture are thanked for their help in sample collection. This work was partly supported by a Grant-in-Aid (No. 13660171) from the Japan Ministry of Education, Culture, Sports, Science and Technology to A. Goto. Correspondence to:Akira Goto     

Two mating groups of Polysphondylium pallidum, a dictyostelid cellular slime mold

 Seven strains representative of Polysphondylium pallidum were examined in terms of mating relationship and morphology. By mating tests, two heterothallic mating groups were detected. By morphological comparisons, they were clearly different in number of branches and in shape of bases and tip cells of sorophores. These results suggested that these two mating groups were distinct taxa. Received: January 23, 2002 / Accepted: August 30, 2002 Present address:Kanagawa Prefectural Museum of Natural History, Odawara, Kanagawa, Japan (visiting researcher) Acknowledgments I thank Dr. James C. Cavender, Department of Environmental and Plant Biology, Ohio University, Athens, OH, USA, for providing the cultures of three strains, V-1, WS320, and WS543. Correspondence to:H. Hagiwara     

Spawning season and migration of the myctophid fish <Emphasis Type="Italic">Diaphus theta </Emphasis>in the western North Pacific

 The spawning season, spawning grounds, and migration of the myctophid fish Diaphus theta were studied in the western North Pacific, based on seasonal sampling and estimation of hatching dates. The peak abundance of larvae was observed in July in the transition waters between the Oyashio and Kuroshio fronts. The spawning season ranged from late March to early September, with a peak from May to July. Larvae and juveniles <40 mm in standard length were distributed in the transition waters, whereas larger individuals were collected in the Oyashio and the Western Subarctic waters. These results indicate that this species undergoes a horizontal spawning migration from the Oyashio and Western Subarctic waters into the transition waters crossing the Oyashio front. Received: July 11, 2002 / Revised: October 2, 2002 / Accepted: October 15, 2002 Acknowledgments We are grateful to the captains, officers, and crew of FRV Hokko-Maru, FRV Tankai-Maru, and RV Hakuho-Maru for their assistance at sea. We thank Dr. H. Saito and Mr. H. Kasai for their cooperation in field sampling, and Dr. C. Sassa for his assistance with larval fish taxonomy. Correspondence to:Masatoshi Moku     

A new species of <Emphasis Type="Italic">Lycenchelys</Emphasis> (Perciformes: Zoarcidae) from the Pacific coast of northern Japan

 Lycenchelys tohokuensis sp. nov. is described from five specimens, 199–270 mm SL. Unknown before 1997, specimens were collected along the Pacific side of the Tohoku coast, from off Aomori to Fukushima prefectures at depths of 543–709 m. The species differs from all congeners in the northwestern Pacific chiefly in the lack of pelvic fins, having a double lateral line configuration, relatively low vertebral counts, two rows of palatine teeth, and its head pore pattern. The new species does not appear to be closely related to any other northwestern Pacific Lycenchelys including the only other one without pelvic fins, Lycenchelys fedorovi Anderson and Balanov, 2000. Received: March 26, 2002 / Revised: July 8, 2002 / Accepted: July 9, 2002 Acknowledgments We are indebted to Dr. Daiji Kitagawa, Tohoku National Fisheries Research Institution, and participants in his research cruises, including Drs. T. Hattori, Y. Shimizu, K. Uchikawa, and T. Nobetsu, for collecting and supplying the five specimens described here. We also thank the crews of the R/V Wakataka-Maru and T/V Tanshu-Maru for their help aboard ship. Elaine Heemstra, J.L.B. Smith Institute, South Africa, rendered the figures. Correspondence to:M. Eric Anderson     

Occurrence of sea eels of <Emphasis Type="Italic">Anguilla japonica</Emphasis> along the Sanriku Coast of Japan

 The age and migratory history of the Japanese eel, Anguilla japonica, collected along the Sanriku Coast of Japan, were examined using otolith microstructure and analysis of strontium (Sr) and calcium (Ca) concentrations. The mean Sr : Ca ratios from the elver mark to the otolith edge indicated that there were eels with several general categories of migratory history, including sea eels that never entered freshwater and others which had entered freshwater for brief periods but returned to the estuary or bay. This first evidence of the occurrence of sea eels in this northern area indicates that Japanese eels of the Sanriku Coast do not necessarily migrate into freshwater rivers. Received: May 15, 2002 / Revised: August 4, 2002 / Accepted: August 15, 2002 Acknowledgments We thank Messrs. S. Yamane and K. Morita, and crews of the Otsuchi Marine Research Center, Ocean Research Institute, The University of Tokyo, for their assistance in collecting the eels. This work was supported in part by Grant-in-Aid No. 13760138 from the Ministry of Education, Culture, Sports, Science and Technology, Japan. Correspondence to:Takaomi Arai     

A new perspective on lakes: Kawanabe's latest achievements

In October 1996 the Lake Biwa Museum opened in Oroshimo, Japan after 10 years of planing and construction. It is a most ambitious concept and a very impressive facility. By June of 1997 it had attracted almost 800 000 visitors – almost twice the at tendance predicted for the entire first year of operation.The founding Director General of the Lake Biwa Museum is Hiroya Kawanabe. After a distinguished career as professor of ecology at Kyoto University, Hiroya Kawanabe founded the Centre for Ecological Research at Otsu. After retirement from the university he moved to his new position at the Lake Biwa Museum. Kawanabe-san is internationally recognized for his pioneering and collaborative research on the ayu, Pleoglossus altivelis, Lake Biwa and the ecology of Lake Tanganyika fishes (Kawanabe 1996, Kawanabe et al. 1997). The Lake Biwa Museum is not only the pinnacle of his personal and professional achievements, but also the physical embodiment of his philosophy of science and life.     

Growth history and migration of the threespine stickleback <Emphasis Type="Italic">Gasterosteus aculeatus</Emphasis> in Otsuchi Bay,northeastern Japan

 Both growth and migratory history of the Pacific Ocean forms of the threespine stickleback Gasterosteus aculeatus collected in Otsuchi Bay, northeastern Japan, were examined using otolith microstructure and analysis of strontium (Sr) and calcium (Ca) concentrations with wavelength dispersive X-ray spectrometry by an electron microprobe. Age of the juveniles (21.6–25.9 mm in total length) examined ranged from 101 to 128 days (115 ± 8.5 days; mean ± SD), hatching being estimated as having occurred between March and April 2001. The Sr : Ca ratios in the otoliths changed with both ontogenic development and salinity of the habitat. The otolith Sr : Ca ratios increased gradually from 4.1 × 10⁻³ around the core to 7.5 × 10⁻³ around the edge of the otolith. The fluctuation pattern of otolith Sr : Ca ratios was different from those observed in both freshwater resident and anadromous forms in previous studies. These results suggested that the fish sampled spend their lives in the estuarine and sea environment without freshwater life after hatching. Received: June 5, 2002 / Revised: September 11, 2002 / Accepted: September 24, 2002 Acknowledgments We thank Mr. K. Morita and crews of the Otsuchi Marine Research Center, Ocean Research Institute, The University of Tokyo for their assistance in collecting specimens. This work was supported in part by Grant-in-Aid No. 13760138 from the Ministry of Education, Culture, Sports, Science and Technology, Japan. Correspondence to:Takaomi Arai     

<Emphasis Type="Italic">Umbelopsis gibberispora</Emphasis> sp. nov. from Japanese leaf litter and a clarification of <Emphasis Type="Italic">Micromucor ramannianus </Emphasis>var. <Emphasis Type="Italic">angulisporus</Emphasis>

 Umbelopsis gibberispora is described as a new species in the genus Umbelopsis, Umbelopsidaceae, Mucorales. The species differs from others in this genus by ellipsoidal sporangiospores with unilaterally thickened walls. Phylogenetic analyses based on nuclear large subunit ribosomal DNA (nLSU rDNA) partial sequences suggest that U. gibberispora, U. swartii, and U. westeae form a clade together with the strains of Umbelopsis ramanniana. The ex-type strain of Micromucor ramannianus var. angulisporus is found to be very close to Umbelopsis vinacea, whereas other isolates identified under the former name in the sense of Linnemann fall in the U. ramanniana subclade. For these isolates, a new species, Umbelopsis angularis, is introduced. Phylogenetic relationships among Umbelopsis species are discussed related to their attributes of the sporangial wall and mature spore shapes. Received: August 27, 2002 / Accepted: March 11, 2003 Acknowledgments We thank Dr. Takashi Ohsono, Graduate School of Agriculture, Kyoto University, Japan, for providing the strain of U. gibberispora (CBS 109328). We also thank Dr. Wieland Meyer, University of Sydney, Australia for access to the phylogenetic tree based on ITS sequence data before publishing, and Dr. Richard C. Summerbell, Centraalbureau von Schimmelcultures, the Netherlands, for linguistic corrections.     

A new species of the cardinalfish genus Gymnapogon (Perciformes, Apogonidae) from the Red Sea

 A new cardinalfish species, Gymnapogon melanogaster, is described from two specimens collected at night in the Gulf of Aqaba, Eilat, Israel. This species is characterized by having 9 dorsal and 8 anal fin soft rays; 14–15 pectoral fin rays; 2 + 11 gill rakers; a flat, bifurcated preopercular spine; a naked body without a papillae network; black pelvic fins; and a black stomach. It is similar to Gymnapogon vanderbilti (Fowler, 1938) that is known only from the Line Islands of the Central Pacific Ocean. Received: December 26, 2001 / Revised: June 10, 2002 / Accepted: June 24, 2002 Acknowledgments We thank D. Didier and M. Sabaj of the Academy of Natural Sciences, Philadelphia, for loans of and for taking data from type specimens; T.H. Fraser of the Mote Marine Laboratory, Sarasota, kindly provided data on type specimens. We are grateful to E. Heemstra of the South African Institute for Aquatic Biodiversity, Grahamstown, South Africa, for the artwork presented in this article and to A. Lerner of the Hebrew University, Jerusalem, for his assistance in collecting the specimens. Correspondence to:Ofer Gon