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1.
Reproduction and/or sperm structure was studied in 18 species belonging to five genera of Galeommatidae from Phuket Island, Andaman Sea, Thailand, and Hong Kong. Incubation of the ova occurs in the inner and outer demibranchs of both gills, and sperm is most probably transferred to the ctenidial brood chamber as masses of agglutinated and non-encapsulated spermatozoa. The smallest specimens are males, but change into the female sex and there is a strong indication that some of the species are alternate hermaphrodites. Dwarf males occur in one species (Galeomma layardi). The sperm of all 18 species studied are of the ent-aquasperm type with a more or less hemispherical acrosome that is tilted with respect to the long axis of the moderately elongated nucleus. It is suggested that this type of sperm affords the best autapomorphy for the family Galeommatidae.  相似文献   

2.
Seven new species of the nudibranch genus Trapania Pruvot-Fol,1931 (Goniodorididae) are described from the Indo-West Pacificand an eighth species, T. japonica (Baba, 1935), originallydescribed from one preserved specimen from Japan, is redescribedfrom specimens collected in Hong Kong and tropical eastern Australia.Three of the new species are from temperate south-eastern Australiaand one from tropical eastern Australia. Two species are knownonly from Hong Kong and a third is recorded from the SudaneseRed Sea as well as Hong Kong. Only ten other species of Trapania have been described, sixof those from Europe, and one each from Brazil, California,Japan and New Zealand. The anatomy and external colour patternof these species is compared with that of the seven new species. (Received 12 December 1986;  相似文献   

3.
A new species, Prosopistoma sinense (Ephemeroptera: Prosopistomatidae), is described and illustrated based on egg and larval material from Hong Kong and Guangdong Province, China  相似文献   

4.
We describe and review the subfossil whale bones (mammalian order Cetacea) material from the southern Scandinavian area, that is, Skagerrak, Kattegat, the inner Danish waters and the southwestern Baltic Sea. Fifteen species were identified from the subfossil records of which all, except for the bowhead whale (Balaena mysticetus), have also been encountered in the modern times. Fifty-one specimens were radiocarbon dated covering 12 of the subfossil species. The dates fell in three distinct clusters with a few specimens before the last glacial maximum (LGM), a large group between LGM and the Pleistocene/Holocene boundary (ca. 17.0–11.7 cal. kyr BP), and another large group from ca. 8.0 cal. kyr BP onward. Seventeen of the radiocarbon dated specimens have been subjected to trace element analysis by Instrumental Neutron Activation Analysis. Cross plots of the concentrations of Fe and Zn, and Fe and Co show that it is possible to distinguish crayfish eaters from fish/squid eaters. This can be used as a novel and independent method for the determination to species of whale remains of otherwise uncertain speciation.  相似文献   

5.
Dwarf sperm whales (Kogia sima) are among the most commonly stranded yet least known pelagic cetaceans. Few studies have occurred at sea, and none have quantified temporal and spatial variation in dwarf sperm whale abundance and group size. We assessed seasonal and spatial variation in dwarf sperm whale group size and abundance off Great Abaco Island, Bahamas using surveys within a 126 km2 study area with depths between 2 and 1,600 m. After correcting for survey effort and variation in sighting efficiency among sea states, we found that dwarf sperm whale group size and habitat use varied seasonally. In summer, dwarf sperm whale groups were small (median = 2.5, range = 1–8) and were found only in the two deep habitats within the study area (slope 400–900 m, deep 900–1,600 m). In winter, group sizes increased (median = 4, range = 1–12) and sightings were almost six times higher in the slope habitat, where vertical relief is highest, than other habitats. Our results suggest that studies of pelagic cetaceans and conservation plans must explicitly account for seasonal variation in group size and habitat use.  相似文献   

6.
Hong Kong is famous as a bustling harbour and financial centre, with a dense burgeoning population impacting its coastal environment. Yet, away from the skyscrapers and the pressures of anthropogenic influence, Hong Kong supports a rich marine biodiversity, including corals and mangrove communities. Despite having a small marine area (1651 km2), a total of 5943 marine species have been recorded in Hong Kong waters. Most of these species were reported during the 1980s and 1990s, but new species continue to be discovered, and ~6500 species are estimated. Even though Hong Kong’s marine area is only ~0.03 % of that of China, the number of marine species recorded in Hong Kong already accounts for ~26 % of the total recorded in China. Hong Kong also contributes to a considerable amount (>30 %) of the species records for several taxa including amphipods, cephalopods, polychaetes and fish in the South China Sea, and ~29 % of the hermit crab species in the largest global marine species database, the World Register of Marine Species. These findings demonstrate the rich marine biota found in Hong Kong, which probably reflects Hong Kong’s location within the fringes of the world’s marine biodiversity hotspot.  相似文献   

7.
The Swedenborg whale Balaena swedenborgii Liljeborg, 1867, is a baleen whale species believed to have existed in the North Sea from the period when the inland ice melted around 13,000 before present (BP) until about 8000 years ago. The first bones attributed to this species were found in Sweden in 1705. When whale remains were discovered on the Swedish west coast during the extension work of a motorway extension, it was speculated that this could be a specimen of the extinct Swedenborg whale. The bones were found 72 m above the present-day sea level embedded in glacial mud. Shelly remains of marine organisms were present in the deposit surrounding the whale-fall, and sediments with the associated specimens were therefore collected for further analyses. We applied radiocarbon dating, thin sectioning, morphological analyses, ancient DNA typing and analyses of the associated shelly assemblage in an interdisciplinary effort to understand the circumstances of this fossil whale-fall. Our results show that the whale is not the putative species B. swedenborgii, but a bowhead whale Balaena mysticetus. The results also indicate that the whale must have been rapidly covered by glacial sediments, highlighting the speed of the deglacial process in the area.  相似文献   

8.
Annulatascus joannae, A. lactus, and A. tropicalis are described and illustrated from decaying woody substrata in freshwater habitats in Hong Kong. Annulatascus joannae is distinguished by ellipsoidal and thick-walled ascospores whereas A. lacteus has milky ascomata and A. tropicalis has relatively large, fusiform, 1–3-septate ascospores. Annulatascus biatriisporus is reported as a new record in Hong Kong. A key to and a synoptic table of Annulatascus species are provided. Received: December 14, 2001 / Accepted: July 5, 2002 Acknowledgments C.K.M. Tsui and V.M. Ranghoo are grateful to The University of Hong Kong for the award of postgraduate studentships. A.Y.P. Lee, M.H. Ng, and M.Y. Chan are thanked for photographic and technical assistance. Correspondence to:C.K.M. Tsui  相似文献   

9.
Jay  Barlow 《Marine Mammal Science》2006,22(2):446-464
Cetacean abundance is estimated for the U.S. Exclusive Economic Zone (EEZ) around the Hawaiian Islands based on a ship line‐transect survey from August to November, 2002. Sighting detection functions are estimated from this and other NOAA research surveys from 1986 to 2002 using a new, multiple‐covariate approach. Twenty‐four species were seen on this survey, including two species (Fraser's dolphin [Lagenodelphis hosei] and sei whale [Balaenoptera borealis]) that had not been previously documented to occur in Hawaiian waters. The most abundant large whales are sperm whales (Physeter macrocephalus) and Bryde's whales (Balaenoptera edeni). The most abundant delphinids are pilot whales (Globicephala macrorhynchus), rough‐toothed dolphins (Steno bredanensis), Fraser's dolphins, spotted dolphins (Stenella attenuata), and striped dolphins (Stenella coeruleoalba). Dwarf and pygmy sperm whales (Kogia sima and Kogia breviceps) and Cuvier's beaked whales (Ziphius cavirostris) are also estimated to be quite abundant. Some of the migratory baleen whales (fin whales [Balaenoptera physalus], sei whales, minke whales [B. acutorostrata], and humpback whales [Megaptera novaeangliae]) were seen only late in the survey. Abundance is estimated for 19 cetacean species. The overall density of cetaceans is low in the study area, especially for delphinids. The precision of density and abundance estimates is generally low for all species because of the low number of sightings.  相似文献   

10.
Five species of interstitial opisthobranch gastropod includingone new species, Pseudovermis chinensis are reported from coarsesand in littoral and sublittoral habitats around Hong Kong andthe south China Sea. (Received 15 August 1989; accepted 4 April 1991)  相似文献   

11.
In this study isopod species of the Ross Sea were investigated. Literature until May 2008 was checked to provide an overview of all known and described species in the Ross Sea. This species checklist was then enlarged through material of the 19th Italica expedition in 2004. During this expedition for the first time a small mesh net (500 μm) was used. Nine thousand four hundred and eighty one isopod specimens were collected during this expedition. Through this material the number of isopod species in the Ross Sea increased from 42 to 117 species, which belong to 20 families and 49 genera. Fifty-six percentage of the isopods species collected during the Italica expedition are new to science. The zoogeography of the 117 species was investigated. A non-transformed binary presence-absence data matrix was constructed using the Bray–Curtis coefficient. The results were displayed in a cluster analysis and by nonmetric multidimensional scaling (MDS). This paper gives a first insight into the occurrence and distribution of the isopod species of the Ross Sea.  相似文献   

12.
Cerithideopsilla is a genus of potamidid snails found in high abundance on sedimentary intertidal flats and beneath mangrove trees on continental shores in the tropical and subtropical Indo‐West Pacific region and Mediterranean Sea. Taxonomic revisions have recognized four species, but recent molecular studies have hinted at a higher diversity. Here, we analyse 377 individuals sampled from across the known range and use a combination of molecular phylogenetic (mitochondrial COI and 16S rRNA, and nuclear 28S rRNA genes), statistical (generalized mixed Yule‐coalescent GMYC method) and morphological (shell form) criteria to delimit 16 species. These form four species groups, corresponding with the traditionally recognized species C. alata, C. ‘djadjariensis’ (for which the valid name is C. incisa), C. cingulata and C. conica. Distribution maps were compiled using museum specimens identified by diagnostic shell characters. In combination with the molecular phylogenetic trees, these suggest an allopatric speciation mode, with diversification centred on the East Asian coastline and northern Australia, and a pronounced gap in the ‘eastern Indonesian corridor’, an area of low oceanic productivity. There is, however, frequently geographical overlap between sister species and we suggest from several sources of evidence (e.g. presence of C. conica in isolated saline lakes 900 km from the sea) that post‐speciation transport by migratory birds has occurred. Nine of the 16 species occur between the Gulf of Tonkin and Hong Kong, so southern China is significant for both the evolution and conservation of Cerithideopsilla species. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 114 , 212–228.  相似文献   

13.
Calanus sinicus is a copepod with wide geographical distributionin the continental shelf waters of China. Its occurrence inoceans around Taiwan and Hong Kong is limited by temperatureto winter and spring. We present evidence to show that C. sinicusis carried into the coastal waters of Taiwan and Hong Kong frompopulation centers in the Yellow Sea and the East China Seaby the China Coastal Current during the northeast monsoon periodin winter.  相似文献   

14.

Background  

Capsular serotypes K1 and K2 of Klebsiella pneumoniae are thought to the major virulence determinants responsible for liver abscess. The intestine is one of the major reservoirs of K. pneumoniae, and epidemiological studies have suggested that the majority of K. pneumoniae infections are preceded by colonization of the gastrointestinal tract. The possibility of fecal-oral transmission in liver abscess has been raised on the basis of molecular typing of isolates. Data on the serotype distribution of K. pneumoniae in stool samples from healthy individuals has not been previously reported. This study investigated the seroepidemiology of K. pneumoniae isolates from the intestinal tract of healthy Chinese in Asian countries. Stool specimens from healthy adult Chinese residents of Taiwan, Japan, Hong Kong, China, Thailand, Malaysia, Singapore, and Vietnam were collected from August 2004 to August 2010 for analysis.  相似文献   

15.
香港的两栖和爬行动物   总被引:3,自引:2,他引:1  
赵乐宓 《四川动物》1997,16(2):51-60
香港及其附近水域已有纪录的两栖和爬行动物共4目23科70属107种。本文着重分析陆地与淡水产种类,计有4目21科63属98种,其中目前仅见于香港的特有种4种,物种密度高达897.4/104km2,东洋界种类占绝对优势,其中主要为南中国成分,其次为印度支那成分和印度马来成分,香港与我国东南沿海各省(区)具有很高的生物相似值(>0.4),在动物地理区划上属于东洋界华南区东南沿海亚区。香港地处北半球亚热带季风区,气候温暖湿润,雨量充沛,适合两栖爬行动物的生存和繁衍;但由于面积不大、地貌较不复杂,随着经济的发展和人口的增加,它们生存的地域越来越缩小,再加以人为的干扰,物种和数量有减少的趋势。  相似文献   

16.
17.
There are two recognized species in the genus Berardius, Baird's and Arnoux's beaked whales. In Japan, whalers have traditionally recognized two forms of Baird's beaked whales, the common “slate‐gray” form and a smaller, rare “black” form. Previous comparison of mtDNA control region sequences from three black specimens to gray specimens around Japan indicated that the two forms comprise different stocks and potentially different species. We have expanded sampling to include control region haplotypes of 178 Baird's beaked whales from across their range in the North Pacific. We identified five additional specimens of the black form from the Aleutian Islands and Bering Sea, for a total of eight “black” specimens. The divergence between mtDNA haplotypes of the black and gray forms of Baird's beaked whale was greater than their divergence from the congeneric Arnoux's beaked whale found in the Southern Ocean, and similar to that observed among other congeneric beaked whale species. Taken together, genetic evidence from specimens in Japan and across the North Pacific, combined with evidence of smaller adult body size, indicate presence of an unnamed species of Berardius in the North Pacific.  相似文献   

18.
Thesystematics of the genus Gobio, especially of the populations on the southern Black Sea coast, seems to be still far from being resolved. Seven species were rec-orded from the northern Black Sea coast while three species were recognized from the southern Black Sea coast. We examined in total 43 specimens from K?z?l?rmak River (southern Black Sea basin), 80 specimens from Çoruh River (the Western Cau-casus of the Black Sea basin), 14 specimens from Rioni River (the Western Caucasus of the Black Sea basin), and 6 specimens from Kherota and Shakhe Rivers (the Western Caucasus of the Black Sea basin). Based on an analysis of 32 metric and 5 meristic data as well as the number of vertebrae, we concluded that the K?z?l?rmak and Coruh populations are two distinct, unnamed species, and we describe them here as Gobio kizilirmakensis from the K?z?l?rmak River and G. artvinicus from the Çoruh River.

http://www.zoobank.org/urn:urn:lsid:zoobank.org:pub:1ED54FB1-588F-4412-B376-4BE4E4516EB1  相似文献   

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