饵料对鹄沼枝额虫生长和生殖力的影响

鹄沼枝额虫是一种淡水小型甲壳动物,主要以细菌、有机碎屑和单胞藻等为食.用豆腐、虾片、米糠、大豆、面粉、小球藻6种饵料培养鹄沼枝额虫幼体,经11d培育,结果显示,不同饵料对鹄沼枝额虫生长、成活率有显著影响.方差分析表明,虾片组的鹄沼枝额虫体长增长显著优于其他5种饵料组(P<0.05);小球藻组的鹄沼枝额虫成活率显著高于米糠、豆腐和面粉组(P<0.05),但与虾片和大豆组没有显著性差异(P>0.05).虾片培养的鹄沼枝额虫较其他5种饵料提早1-2d产卵,且初次产卵量和卵径均为最大.用虾片、大豆、米糠、虾片+米糠、大豆+米糠5种饵料投喂性腺刚开始发育的鹄沼枝额虫,经27d培育,结果表明,不同饵料组间的鹄沼枝额虫生殖力差异显著.虾片+米糠培育的鹄沼枝额虫生殖总量显著高于米糠和大豆(P<0.05),而与虾片和大豆+米糠组没有显著性差异(P>0.05).因此,虾片和虾片+米糠是培养鹄沼枝额虫的优质饵料,对其生长和种群增殖有明显的促进作用.     

Daphnia curvirostris Eylmann in Japanese high mountain waters (Cladocera: Daphniidae)

A species of Daphnia, Daphnia curvirostris Eylmann, found in high mountain lakes and ponds in central Japan is described. Although there were some differences in the shape of the male rostrum and the chromosome number between European populations as described by Johnson (1952) and Trentini (1980), and Japanese ones collected from high mountain waters, Japanese specimens had many characteristics similar to the taxon D. curvirostris of Europe.     

Allozyme diversity in Japanese populations of Hemerocallis thunbergii, H. middendorffii, and H. exaltata (Liliaceae)

Eight populations of Hemerocallis thunbergii, H. middendorffii , and H. exaltata from Japan were analyzed by starch gel electrophoresis to measure genetic variation at ten allozyme loci. The former two species are widely distributed in eastern Asia, whereas H. exaltata is restricted to the Tobishima and Sado Islands in western Japan. Populations of the three species maintain high levels of allozyme variation: mean expected heterozygosities were 0.288, 0.209, and 0.169, respectively. The UPGMA phenogram obtained from Nei's genetic distance values indicated that H. exaltata is allozymically the most distinct species, whereas populations of H. thunbergii and H. middendorffii are closely related. However, based on gross morphology H. exaltata and H. middendorffii are closely related. This discrepancy and the observed high levels of allozyme variation within populations of the three Hemerocallis species in Japan may in part be due to genetic change among populations of the two Japanese archipelago species.     

Occurrence of the endangered species Nitellopsis obtusa (Charales,Charophyceae) in western Japan and the genetic differences within and among Japanese populations

Nitellopsis obtusa (Charales, Charophyceae) are widely distributed from Europe to Asia; however, this species has been recorded in only the five lakes in central Honshu in Japan. This species was thought to be extinct in Japan, but was rediscovered in limited areas of Lake Kawaguchi in central Honshu. More recently, we discovered more Japanese populations of N. obtusa in Lake Biwa in western Honshu, and it became clear that the species had a broader distribution in Japan than originally believed. In addition, although only male or female thalli have been collected at each lake, both male and female thalli were found from Lake Biwa. This is the first report of a potentially sexual population of N. obtusa in Japan. The DNA sequences of three chloroplast DNA markers, including both coding and non‐coding regions, were identical in all specimens from Lake Kawaguchi and Lake Nojiri (Central Honshu), and differed from those of Lake Biwa and German specimens. Although Japanese and German specimens were genetically similar, Japanese specimens displayed considerable genetic diversity according to locality.     

A conflict of morphological and genetic patterns in the Australian anostracan Branchinella longirostris

Branchinella longirostris is a fairy shrimp endemic to ephemeral pools on granite outcrops in southwestern Australia. The patchy nature of its habitat is thought to result in a high degree of subdivision among populations, potentially promoting speciation. We combined traditional taxonomy with a molecular phylogeny of cytochrome c oxidase I (COI) to test whether B. longirostris could be a species complex and whether the frontal appendage on the second antennae of males is a suitable character to differentiate new species. We also used nested clade analysis to assess the population structure and demographic factors explaining the geographical distributions of the mt DNA haplotypes. The results show that shapes of frontal appendages are not congruent with the mitochondrial genetic structure; however, they are positively correlated with geography. We conclude that the frontal appendage in B. longirostris is either subject to selection or a result of morphological plasticity; thus, its use in taxonomy remains uncertain. The intraspecific divergence in B. longirostris (≤7.7%) was approximately one third as large as the divergence from the outgroup (17.8–20.8%) and well within the ranges of divergence found in other crustaceans with fragmented population structure. There is some association between genetic structure and geography, resulting in the inference of restricted gene flow with isolation by distance and allopatric fragmentation as the most suitable models of the historical population processes. It is likely that the current distribution of haplotypes resulted from the dispersal of resting eggs by stochastic events (wind, birds) rather than from a fragmentation of previously continuous habitat as the estimated evolutionary age of the species (≤6.1 my) is much younger than its habitat (50–100 my). We found some evidence on the genetic level to support the hypothesis that B. longirostris could be a complex of species; however, the lack of correlation between the genetic pattern and the reproductively important frontal appendage lends a support to a view that B. longirostris is a single species with an exceptionally high intraspecific diversity.     

COMPARATIVE MORPHOLOGY, CROSSABILITY, AND TAXONOMY WITHIN THE CALOGLOSSA CONTINUA (DELESSERIACEAE, RHODOPHYTA) COMPLEX FROM THE WESTERN PACIFIC

Systematic studies were undertaken on the Caloglossa continua ( Okamura) King et Puttock complex from Japan, Singapore, and Australia, based on morphology and reproductive compatibility. Specimens from Japan had two to six cell rows derived from a nodal axial cell, at the margin opposite the branch, whereas those from Australia possessed only a single cell row. Specimens from Singapore formed one to four cell rows per nodal axial cell and always contained at least one single cell row on any one thallus. These differences were maintained in cultured materials over a range of temperatures or salinities. Type material of C. continua had the same morphology as the Japanese specimens in this study. Carpospores discharged from the Japanese isolate germinated at 10°C, whereas those from Singapore and Australia died at this temperature. In hybridization experiments, the Japanese entity was completely nonfertile with both the Singaporean and Australian isolates. Many pseudocystocarps were produced in the crossing between the male from Australia and the female from Singapore, although the reciprocal combination did not produce any such structures. On the basis of the discontinuous morphology coupled with the complete reproductive isolation, the entities from Singapore and Australia are described here as C. monosticha sp. nov. The entities with multiple cell rows likely expanded their geographic range from tropical regions, where the majority of Caloglossa species are now distributed, to high-latitude regions, and such an expansion would be associated with acquiring low-temperature tolerance .     

Anopheles culicifacies Y-chromosome dimorphism indicates sibling species (B and E) with different malaria vector potential in Sri Lanka

In Sri Lanka, malaria is transmitted mainly by Anopheles culicifacies Giles sensu lato (Diptera: Culicidae). In India, this nominal taxon comprises sibling species A, B, C, D and E, distinguished by their chromosome morphology. Species B (identified by polytene chromosome sequence Xab, 2g1 + h1) is not such an efficient vector of malaria as other members of the An. culicifacies complex in India. All specimens of An. culicifacies s.l. examined from Sri Lanka possess Xab, 2g1 + h1 polytenes, previously interpreted as species B, despite their important vector status. Recently, species E was described from Rameshwaram Island (Tamil Nadu, India) between Sri Lanka and the Indian mainland, where both species B and E are sympatric. Species B and E share polytene sequence Xab, 2g1 + h1 but differ by the mitotic Y-chromosome being acrocentric in species B, submetacentric in species E, the latter implicated as vector of vivax malaria. From May 1999 to January 2000, we surveyed Y-chromosomes of male progeny from An. culicifacies Xab, 2g1 + h1 females collected from cattle bait in diverse malarious districts of Sri Lanka: Badulla, Monaragala, Puttalam and Trincomalee. Karyotypes of readable quality were obtained from 42/83 families examined, with overall proportions 24% acrocentric and 76% submetacentric Y-chromosome carriers, both types being sympatric in at least 3/4 localities sampled. By analogy with the situation on Rameshwaram Island, we interpret these observations to demonstrate widespread presence of two members of the An. culicifacies complex in Sri Lanka, their karyotypes being compatible with species B and E, the latter predominant and having greater vector potential.     

Multiple population structure of the giant mottled eel, Anguilla marmorata

The population structure of the giant mottled eel, Anguilla marmorata, was investigated with mitochondrial and microsatellite DNA analyses using 449 specimens from 13 localities throughout the species range. Control region F-statistics indicated the North Pacific (Japan, Taiwan, Philippines, Sulawesi), South Pacific (Tahiti, Fiji, New Caledonia, Papua New Guinea), eastern Indian Ocean (Sumatra), western Indian Ocean (Réunion, Madagascar), Ambon, and Guam regions were significantly different (Phi(ST) = 0.131-0.698, P < 0.05) while only a few differences were observed between localities within the South Pacific. These regions were roughly clustered in the neighbour-joining tree, although Ambon individuals were mainly divided into North and South Pacific groups. Analysis with eight microsatellite loci showed almost identical results to those of the control region, except no genetic difference was observed between the western and eastern Indian Ocean (F(ST) = 0.009, P > 0.05). The Bayesian cluster analysis of the microsatellite data detected two genetic groups. One included four North Pacific localities, and the other included eight localities in the South Pacific, Indian Ocean, and Guam, but Ambon individuals were evenly assigned to these two groups. These results showed that A. marmorata has four genetically different populations (North Pacific, South Pacific, Indian Ocean, Guam region). The North Pacific population is fully panmictic whereas the South Pacific and Indian Ocean populations have a metapopulation structure. Interestingly, Guam was suggested to be inhabited by a reproductive population restricted to that region, and the individuals from the North and South Pacific populations co-exist in Ambon.     

Lenomyrmex, an enigmatic new ant genus from the Neotropical Region (Hymenoptera: Formicidae: Myrmicinae)

Abstract. We describe a new myrmicine ant genus, Lenomyrmex , with four new species: L. mandibularis (type species) and L. foveolatus from Colombia, L. wardi from Ecuador and Colombia, and L. costatus from Panama. The new taxon is clearly distinguished from other myrmicine ants by the following combination of characters: (1) mandibles elongate-triangular, with crenulate masticatory margin three times longer than basal margin, and bearing a series of ten to twenty minute peg-like denticles that arise along and immediately behind the masticatory margin; (2) frontal lobes poorly expanded laterally, partly covering the antennal fossae; (3) large and deep antennal fossae; (4) antennal scrobes absent; (5) eyes protuberant; (6) petiole pedunculate, with poorly defined node and with an anteroventral subpetiolar process pointed anteriorly. The affinities of this new taxon within Myrmicinae remain unclear and the observed characters do not permit it to be included satisfactorily in any of the known tribes or genus groups of the subfamily.     

Evolutionary relationships and reproductive isolating mechanisms in the rice frog (Fejervarya limnocharis) species complex from Sri Lanka, Thailand, Taiwan and Japan, inferred from mtDNA gene sequences, allozymes, and crossing experiments

The rice frog (Fejervarya limnocharis) species complex is widely distributed, from India to Japan, and most prevalently in Southeast Asia. Conspicuous morphological variation has been reported for this species complex throughout its distribution range. In the present study, we used mtDNA gene sequence and allozyme analyses to infer evolutionary affinities within this species complex using eight populations (Sri Lanka; Bangkok and Ranong in Thailand; Taiwan; and Hiroshima, Okinawa, Ishigaki and Iriomote in Japan). We also conducted crossing experiments among four populations from Japan, Thailand, and Sri Lanka in order to find out more about the reproductive isolating mechanisms that might exist among the East, Southeast, and South Asian populations of this species complex. The crossing experiments revealed that the Sri Lanka population is reproductively isolated from the Hiroshima, Bangkok, and Ranong populations by complete hybrid inviability, and that the Bangkok population may be reproductively isolated from the Hiroshima population by partial hybrid inviability. Thus, it is not unreasonable to regard the Sri Lanka population as a species separated from F. limnocharis. The mtDNA and allozyme data showed that the Ranong population is most closely related to the Bangkok population in nuclear genome, but more similar to the Okinawa and Taiwan populations in mtDNA genome. The present, preliminary survey may raise questions about the species status of these particular populations and also about the nature of the biological species concept.     

Ultrastructure of the antennal sensorial appendage of larvae of Ophonus ardosiacus (Lutshnik, 1922) (Coleoptera, Carabidae) and possible correlations between size and shape and the larval feeding habits

The antennal sensory appendage morphology was studied in 19 species of carabid beetle larvae using scanning electron microscopy. Shape and size of the organ has been re-examined in selected taxa and are compared to figure out possible correlations between antennal sensory structures and larval morphoecological types. Morphometric analysis shows no correlation between antennal sensory appendage dimension and the four most common behavioural types. The ultrastructure of this sensory organ is described for larvae of Ophonus ardosiacus and the possible function is discussed. Olfactory function has been indicated as the most probable. The high number of chemosensory neurons of this multiporous organ suggests a possible ability of fine odour discrimination related to prey choice or host location.     

Morphological and Molecular Characterization of Reared Parasitoid Wasps of the Genus Glyptapanteles Ashmead 1904 (Insecta: Hymenoptera: Braconidae: Microgastrinae) Associated with Lepidoptera in India

Glyptapanteles Ashmead (Hymenoptera: Braconidae: Microgastrinae) is a cosmopolitan group of hyperdiverse parasitic wasps. The genus remains taxonomically challenging in India due to its highly speciose nature, morphological similarity amongst species and negligible host records. The Indian fauna is one of the most diverse and also the least studied. The present study is based on 60 populations reared from 35 host species, 100+ individual caterpillar rearings (1100 wasp specimens pinned and 2000 in alcohol) and from 12 different geographical locations of the country (11 states and one Union territory) that represent 26 provisional Glyptapanteles species within 8 species-groups. Out of 60 populations, phylogenetic analyses were performed on 38 based on mitochondrial cytochrome oxidase subunit I (COI) nucleotide sequences. Maximum likelihood and Bayesian inference methods displayed three and four major discrete Glyptapanteles clades, respectively. In clade A very few Indian species were grouped along with Neotropical and Thailand species. The other clades B and C grouped the majority of the Indian species and showed considerable host specificity in both the trees. All parasitic wasp species were gregarious in nature, except for two populations. Three different sets of data (morphology, host records, and COI) were integrated in order to generate accurate boundaries between species/species-groups. Illustrations of all parasitized caterpillars/cocoons and 42 habitus views of Glyptapanteles spp., distributional information, and GenBank accession numbers, are presented. The present study, perhaps the most comprehensive done to date in India, suggests the presence of several additional Glyptapanteles species, which were previously unrecognized.     

Comparison of attractiveness in Japan and China of three synthetic pheromone blends based on geographic variations in the rice leaffolder,Cnaphalocrocis medinalis(Lepidoptera: Pyralidae)

Field bioassays using three different synthetic sex pheromone blends (Indian, Philippine and Japanese) based on geographic variations of Cnaphalocrocis medinalis Guenée were carried out at 11 sites in Japan and in Hangzhou, China. In all of the tests, only the Japanese pheromone blend attracted a significant number of male moths, while the Indian and Philippine pheromone blends showed no marked activity. The findings in Japan showed no evidence that moths of Philippine or Indian origin were able to migrate to Japan. The results from China also showed that most populations of C. medinalisin the Hangzhou region responded to the Japanese blend. This is consistent with the current hypothesis that most populations of C. medinalisin Japan are migrants from areas to the south of the Yangzhe Valley, including the region surrounding Hangzhou, China. Furthermore, populations in the Hangzhou region can not hibernate, but are considered migrants from the southernmost parts of China and southeast Asian countries such as Vietnam where they breed continuously. Consequently, at least some populations in these areas may respond to the Japanese pheromone blend.     

On the Taxonomy and Morphology of the Pine Wood Nematode, Bursaphelenchus xylophilus (Steiner &Buhrer 1934) Nickle 1970

During the past 3 yr, nematologists in the United States have found specimens of Bursaphelenchus sp. in the wood of dead and dying pine trees. This nematode-host association resembles a similar interaction reported from Japan where pine trees are being killed by the pine wood nematode. This taxonomic research was conducted to determine if the Japanese pine wood nematode and similar populations in the United States are of the same species. Based upon typical morphological characters of original specimens of Bursaphelenchus xylophilus (Steiner and Buhrer 1934) Nickle 1970 that were rediscovered in the USDA Nematode Collection and genetic crosses among the Japanese and American nematode populations, it was concluded that they are all the same species, B. xylophilus.     

First record of the family Thamnocephalidae (Crustacea: Anostraca) from Southeast Asia and description of a new species of Branchinella

During a two-year investigation of freshwater microcrustaceans in Thailand, an undescribed species of fairy shrimp of the genus Branchinella Sayce, 1903 in the family Thamnocephalidae, was discovered. This is the first record of the genus and the family from Southeast Asia and the second anostracan reported from Thailand. The new species, Branchinella thailandensis n. sp. appears to be morphologically intermediate between B. kugenumaensis (Ishikawa, 1895) from Japan and east China, and B. madurai Raj, 1951 from India and Pakistan. B. thailandensis n. sp. was collected from several temporary ponds in 11 provinces of the northeast and the central Thailand, often co-occurring with Streptocephalus sirindhornae Sanoamuang, Murugan, Weekers & Dumont, 2000.     

Phylogeographic Analysis of the Firefly, Luciola lateralis, in Japan and Korea Based on Mitochondrial Cytochrome Oxidase II Gene Sequences (Coleoptera: Lampyridae)

Luciola lateralis is widely distributed throughout the Korean Peninsula, northeast China, Sakhalin, and Japan. Two ecological types are recognized in Japan based on flash and hatching time characteristics. The mitochondrial cytochrome oxidase II gene was surveyed by restriction fragment length polymorphism analysis for Japan (46 populations) and Korea (two populations). Eleven haplotypes were detected. Gene trees revealed that haplotypes between Japan and Korea are much more differentiated in nucleotide sequences (8.1%) than those within Japan (0.3-1.4%) and Korea (0.7%). Haplotypes between Honshu and Hokkaido are not separated as clades, and the two ecological types cannot be segregated from each other phylogenetically. We suggest that the Japanese populations of this species may have dispersed within one million years ago and that ecological differences may be the result of physiological adaptation to cold climates.     

Genetic differentiation and zoogeography of Asian Suncus murinus (Mammalia: Soricidae)

Protein electrophoresis was used to assess the phylogenetic relationships of populations of the phenotypically variable Asian house shrew Suncus murinus. These populations represent a sample of both commensal and wild forms. They were compared to another taxon, S. montanus , which was formerly considered conspecific with S. murinus. Suncus dayi was used as an outgroup in all phylogenetic reconstructions. Within the S. murinus lineage, the allozyme data show very low levels of genetic differentiation among both wild and commensal Southeast Asian and Japanese samples when compared to the Indian populations. This pattern is consistent with the classical hypothesis of a recent introduction by man in Eastern Asia. The higher genetic diversity found within S. murinus from India, as well as previous mitochondrial and karyological results suggest that this area is the probable centre of origin for the species. Although the lack of gene flow between S. murinus and S. montanus is clearly established in an area of sympatry in Southern India, one Asian house shrew sampled in Nepal was more closely related to S. montanus. This could either reflect the retention of an ancestral polymorphism, or result from a hybridization episode between S. murinus and S. montanus. Similar conclusions were also suggested in mitochondrial DNA studies dealing with animals sampled in the Northern parts of the Indian subcontinent. Clearly, further data on Suncus from this area are needed in order to assess these hypotheses.     

Trichomanes vamana, a new filmy fern species (Hymenophyllaceae - Pteridophyta) from India

Trichomanes vamana, a new species of filmy fern from South India is described and illustrated. Key to South Indian species of Trichomanes subg. Didymoglossum sect. Microgonium and affinities of this taxon with T.mindorense are discussed