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1.
Merel L. Dalebout C. Scott Baker Debbie Steel Kirsten Thompson Kelly M. Robertson Susan J. Chivers William F. Perrin Manori Goonatilake R. Charles Anderson James G. Mead Charles W. Potter Lisa Thompson Danielle Jupiter Tadasu K. Yamada 《Marine Mammal Science》2014,30(3):1081-1108
We present genetic and morphological evidence supporting the recognition of a previously synonymized species of Mesoplodon beaked whale in the tropical Indo‐Pacific, Mesoplodon hotaula. Although the new species is closely‐related to the rare ginkgo‐toothed beaked whale M. ginkgodens, we show that these two lineages can be differentiated by maternally (mitochondrial DNA), biparentally (autosomal), and paternally (Y chromosome) inherited DNA sequences, as well as by morphological features. The reciprocal monophyly of the mtDNA genealogies and the largely parapatric distribution of these lineages is consistent with reproductive isolation. The new lineage is currently known from at least seven specimens: Sri Lanka (1), Gilbert Islands, Republic of Kiribati (1+), Palmyra Atoll, Northern Line Islands, U.S.A. (3), Maldives (1), and Seychelles (1). The type specimen (Sri Lanka) was described as a new species, M. hotaula, in 1963, but later synonymized with M. ginkgodens. This discovery brings the total number of Mesoplodon species to 15, making it, by far, the most speciose yet least known genus of cetaceans. 相似文献
2.
Lisa T. Ballance Robert L. Pitman Jay Barlow Todd Pusser Annamaria I. DeAngelis Craig Hayslip Ladd Irvine Debbie Steel C. Scott Baker Daniel Gillies Simone Baumann-Pickering Jennifer S. Trickey Brian Gisborne 《Marine Mammal Science》2024,40(1):123-142
Although Hubbs' beaked whale (Mesoplodon carlhubbsi) was previously known from over 60 strandings on both sides of the North Pacific, it had been identified alive in the wild only once, off Oregon in 1994. In September 2021, we conducted a search effort for beaked whales off the coast of Oregon using a towed hydrophone array and a visual search team. Approximately 350 km off the Columbia River mouth, we detected the vocalizations of an unidentified mesoplodont whale; we stopped our vessel and waited in the area until two unidentified juvenile Mesoplodon surfaced and stayed near our vessel for almost 2 hr. During that time, we took numerous photographs and videos, made behavioral observations, and recorded their vocalizations. The DNA sequence from a biopsy sample identified them as M. carlhubbsi. In this paper, we discuss our biological observations, including color patterning and acquired markings, behavioral observations, and describe for the first time the acoustic characteristics of this species. We confirm that M. carlhubbsi is the source of a previously unidentified acoustic signal known as BW37V, and we update what is known about the at-sea distribution of this species based on previous recordings and observational records. 相似文献
3.
The diets of the mangrove crabs, Metopograpsus frontalis Miers and Perisesarma bidens de Haan, were investigated monthly for 13 months at two Hong Kong mangroves, to examine possible spatial and temporal influences
on their feeding ecology. In both species, a higher degree of gut fullness was observed in summer (May–September) than in
winter, suggesting a reduction in winter foraging activity. M. frontalis was omnivorous, with animal and plant materials and inorganic sediments being the major food items. P. bidens was detritivorous, with plant materials and inorganic sediment dominating the gut contents. M. frontalis is, therefore, an opportunistic feeder, whilst P. bidens, like many other members of the Sesarmidae, is a detritivore. Some degree of seasonal variation was shown in the diet of
M. frontalis (with more algal material in winter) and P. bidens (with more sediments in summer), but diets were similar between sexes in both species. The dietary pattern of M. frontalis also varied between sites. The diets of the crabs, therefore, appear to be a result of the interplay between the seasonal,
physical climate and biological factors, especially food availability and the crabs’ ecology. Results suggest that the predatory
role of Metopograpsus, which has been poorly studied, is potentially important to estuarine food webs; whilst the trophic importance of sesarmid
crabs, such as Perisesarma, especially in mangrove outwelling, should be critically re-evaluated. 相似文献
4.
Pamela S. Soltis Gregory M. Plunkett Stephen J. Novak Douglas E. Soltis 《American journal of botany》1995,82(10):1329-1341
Genetic diversity in the introduced diploids Tragopogon dubius, T. porrifolius, and T. pratensis and their neoallotetraploid derivatives T. mirus and T. miscellus was estimated to assess the numbers of recurrent, independent origins of the two tetraploid species in the Palouse region of eastern Washington and adjacent Idaho. These tetraploid species arose in this region, probably within the past 50–60 yr, and provide one of the best models for the study of polyploidy in plants. The parental species of both T. mirus and T. miscellus have been well documented, and each tetraploid species has apparently formed multiple times. However, a recent survey of the distributions of these allotetraploids revealed that both tetraploid species have expanded their ranges considerably during the past 50 yr, and several new populations of each species were discovered. Therefore, to evaluate the possibility that these recently discovered populations are of recent independent origin, a broad analysis of genetic diversity in T. mirus, T. miscellus, and their diploid progenitors was conducted. Analyses of allozymic and DNA restriction site variation in all known populations of T. mirus and T. miscellus in the Palouse and several populations of each parental diploid species revealed several distinct genotypes in each tetraploid species. Four isozymic multilocus genotypes were observed in T. mirus, and seven were detected in T. miscellus. Tragopogon mirus possesses a single chloroplast genome, that of T. porrifolius, and two distinct repeat types of the 18S-26S ribosomal RNA genes. Populations of T. miscellus from Pullman, Washington, have the chloroplast genome of T. dubius; all other populations of T. miscellus have the chloroplast DNA of T. pratensis. All populations of T. miscellus combine the ribosomal RNA repeat types of T. dubius and T. pratensis, as demonstrated previously. When all current and previously published data are considered, both T. mirus and T. miscellus appear to have formed numerous times even within the small geographic confines of the Palouse, with estimates of five to nine and two to 21 independent origins, respectively. Such recurrent polyploidization appears to characterize most polyploid plant species investigated to date (although this number is small) and may contribute to the genetic diversity and ultimate success of polyploid species. 相似文献
5.
The effects of five diets (larvae of Galleria mellonella L., larvae of Spodoptera littoralis (Boisduval), eggs of Ephestia kuehniella Zeller, cysts of Artemia franciscana Kellogg and an artificial diet based on bovine meat) on development, survival and reproduction of two predatory stinkbugs,
Picromerus bidens L. and Podisus maculiventris (Say), were studied in the laboratory. Both species successfully completed immature development on the foods offered, except
for P. bidens on cysts of A. franciscana. Significant effects of diet on developmental duration were found in both species. Total developmental time from second instar
to adult ranged from 25.0 to 41.5 days and from 18.7 to 46.0 days in P. bidens and P. maculiventris, respectively. Nymphal survival of P. maculiventris was superior to that of P. bidens on all diets tested. Nymphal survival of P. maculiventris was greater than 92% on all diets except on A. franciscana cysts, yielding only 50% survival to adulthood. Survival of P. bidens fed on eggs of E. kuehniella was higher than that of conspecifics fed on caterpillar prey or artificial diet (89% on flour moth eggs vs. 68 and 80% on
G. mellonella and S. littoralis and only 50% on meat diet). Fresh weight of newly emerged females of both pentatomids was affected by the diet offered to
the predators during their nymphal stage. Females of P. maculiventris produced viable eggs on all diets except on cysts of A. franciscana and had mean fecundities of 691, 436, 608 and 344 eggs per female on S. littoralis, G. mellonella, E. kuehniella eggs and the meat diet, respectively. Females of P. bidens laid eggs only on live prey with mean fecundities of 94 and 38 eggs per female on S. littoralis and G. mellonella, respectively. The results indicate a lower nutritional plasticity of P. bidens as compared with P. maculiventris.
An erratum to this article can be found at 相似文献
6.
Beaked whales (Ziphiidae) often show highly specialized features, involving bone morphology or structure, in the rostral region of their skulls. Previous studies revealed an extremely derived and peculiar histological structure in the rostrum of the extant Mesoplodon densirostris. In order to assess if this structure is a general feature of ziphiids, the swollen premaxillae of Aporotus recurvirostris, a Miocene species from the North Sea, were studied histologically. These bones are pachyostotic and strongly osteosclerotic. However, their structural organization is entirely different from that of M. densirostris rostrum: they are basically made of a non-remodeled, laminar tissue that was cyclically deposited by the periosteum. As compared to the generalized structure of the premaxillae of toothed whales exemplified by the bottlenose dolphin, Tursiops truncatus, the pachyostotic condition of Aporotus premaxillae was obviously due to a particularly high and sustained growth-rate, occurring in a dorso-lateral direction. The osteosclerotic structure of these bones resulted from a complete lack of inner resorption activity. The histological features of Aporotus premaxillae indicate that these bones are not likely to have been hypermineralized, and thus, their physical properties must have differed from those of the M. densirostris rostrum. The possible functional involvements of rostral peculiarities in beaked whales are discussed with reference to the whole set of available comparative data. 相似文献
7.
Length–weight relationships of nine fish species from the Tongjiang section of the Songhua River,China
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T. B. Huo M. Y. Yuan J. L. Wang P. L. Li W. Liu X. C. Wu 《Zeitschrift fur angewandte Ichthyologie》2017,33(4):848-850
Length–weight relationships were evaluated for nine fish species from the Tongjiang section of the Songhua River in China. A total of 675 fish specimens were collected from 4 May to 29 October 2014. Length–weight relationships for six fish species (Romanogobio tenuicorpus, Leuciscus waleckii, Opsariichthys bidens, Microphysogobio amurensis, Pelteobagrus ussuriensis and Misgurnus mohoity) were new to FishBase in 2015, but the length–weight relationships of P. ussuriensis was studied by Ma in 2015. New data on M. mohoity is offered, and this study also shows new maximum total lengths for three fish species. The r2 values ranged from .95 to .99. Values of b varied from 2.504 to 3.471. 相似文献
8.
Gina L. Lonati Emily M. Singleton Caitlin E. Phelps Heather N. Koopman D. Ann Pabst 《Marine Mammal Science》2019,35(2):595-616
Cetacean integument serves many functional roles, including contribution to whole body buoyancy. The blubber of the integument of different cetacean species contains varying concentrations of triacylglycerols (TAG) and wax esters (WE); generally, these lipid classes have different densities. Integument can also experience a wide range of temperatures during a dive, so its density may change with depth. The goals of this study were to measure integument density and isolated blubber lipid density in three deep‐diving odontocete species (n = 3–4)—short‐finned pilot whales (Globicephala macrorhynchus), pygmy sperm whales (Kogia breviceps), and Gervais' beaked whales (Mesoplodon europeaus)—at different temperatures (6°C–35°C), and to relate these densities to lipid content and composition. Kogia and Mesoplodon integument and isolated lipids had high WE content (78.7–99.5 wt%) and were less dense (by 1.7%–9.3%) than those of Globicephala, which were composed predominately of TAG. Generally, densities increased as temperature decreased. Changes in integument densities mirrored those of isolated lipid densities, suggesting that blubber lipids are largely responsible for the buoyant properties of cetacean integument. These data demonstrate that the contribution of the integument to whole body density depends on lipid class and temperature, and therefore may provide useful, species‐specific correction factors for diving energetics models. 相似文献
9.
Two beaked whales identified as Sowerby's beaked whale (Mesoplodon bidens) were observed in sea state 0–1 on 16 July 1995 at 71°30′N 04°00′E in the Norwegian Sea. A number of morphological features,
such as dentition, were clearly seen during the encounter. The Sowerby's beaked whale's core distribution is in the North
Sea and the previous northernmost sighting was made at 63°06′N 00°41′E. According to the literature, the species has never
been recorded in the polar zone. The sighting in the Norwegian Sea suggests that the current data on the species distribution
is uncertain, and that its range may include the polar waters of the Norwegian Sea.
Received: 24 April 1996 / Accepted: 25 August 1996 相似文献
10.
Currently, 20 species of the genus Rhyacophila are known from Vietnam. Of these, 17 species are distributed among eight species groups, with three species unassigned. Examination of material collected by personnel of the Royal Ontario Museum in Toronto, Canada has revealed six new species and five new records of Rhyacophila from Vietnam, distributed among six species groups, four of which are new to Vietnam. Newly described species include: Rhyacophila smithi, Rh. curriei, Rh. laocai, Rh. meyi, Rh. olahi, and Rh. fernandi. Rhyacophila bidens Kimmins, Rh. inaequalis Denning and Schmid, Rh. lhabu Schmid, Rh. malayana Banks, and Rh. rhombica Martynov are recorded from Vietnam for the first time. The females of four species, Rh. bidens, Rh. immaculata Mey, Rh. malayana Banks, and Rh. tamdaona Oláh, are described for the first time. All 31 species of Rhyacophila now known from Vietnam are included in this work, organized by branch and species group. 相似文献
11.
A new anisakid nematode, Anisakis nascettii n. sp., is described from beaked whales Mesoplodon spp. off the coast of New Zealand and South Africa. Morphological and molecular (allozymes and mtDNA cox2 sequence) data were used for diagnostic and identification purposes. Among the 19 allozymes studied, 10 were found to be
unique and characteristic for A. nascettii n. sp. Analysis of allozymes demonstrated reproductive isolation from A. ziphidarum Paggi, Nascetti, Webb, Mattiucci, Cianchi & Bullini, 1998 and mtDNA cox2 sequences depict this Anisakis species as a distinct and unique entity. Key morphological diagnostic traits for A. nascettii with respect to the genetically closely related species A. ziphidarum include: spicule length, the spicule/body length ratio, the arrangement of the caudal papillae and the shape of the plectanes
of the adult males. Genetic data confirmed that Anisakis sp. A of Pontes et al. (2005), which was partly described by Iglesias et al. (2008), and Anisakis sp. of Valentini et al. (2006) are conspecific with A. nascettii. Both molecular and morphological data indicate that the new species belongs to the ‘ziphidarum-group’; however, it is genetically very distinct from A. ziphidarum (D
Nei
= 0.69, K2P = 0.09), as well as from all of the previously genetically characterised Anisakis spp. All tree topologies inferred by different methods (MP, NJ and Bayesian) support the finding that A. nascettii n. sp. and A. ziphidarum are sister-species. It is also confirmed that A. nascettii n. sp. is, at the adult stage, a parasite of beaked whales of the genus Mesoplodon, whereas, as a larva, it has been identified from the squid Moroteuthis ingens Smith. Furthermore, Mesoplodon bowdoini Andrews represents a new host record for A. ziphidarum. The parallelism between the clade formed by these two anisakine taxa, i.e. A. ziphidarum and A. nascettii, and that formed by their definitive hosts further supports the hypothesis of host–parasite co-evolutionary relationships,
as previously suggested for Anisakis spp. and their cetacean hosts. 相似文献
12.
DOUGLAS E. SOLTIS EVGENY V. MAVRODIEV STEPHEN C. MEYERS PAUL M. SEVERNS LINJING ZHANG MATTHEW A. GITZENDANNER TINA AYERS MICHAEL CHESTER PAMELA S. SOLTIS 《Botanical journal of the Linnean Society. Linnean Society of London》2012,169(2):297-311
The allotetraploids (2n = 24) Tragopogon mirus and T. miscellus have become textbook examples of recently and recurrently formed allopolyploids. Both species formed following the introduction of three diploids, T. dubius, T. porrifolius and T. pratensis (each with 2n = 12), from Europe into the Palouse region of eastern Washington and adjacent Idaho, USA, in the early 1900s. The parentage of both allotetraploids is well documented (T. mirus = T. dubius × T. porrifolius; T. miscellus = T. dubius × T. pratensis), and both allotetraploids have formed repeatedly in the past approximately 80 years in the Palouse. On a larger geographical scale, T. mirus has also been reported from Flagstaff, Arizona (AZ), and more recently from Oregon (OR). However, the populations from OR and AZ have not been previously analysed with molecular markers to test the hypothesis of separate origin (vs. long‐distance dispersal). Here, we show that both the AZ and OR collections of T. mirus combine distinctive parental genotypes and are genetically differentiated from the T. mirus genotypes found in the Palouse. The OR sample of T. mirus has a genetically distinct T. dubius contribution that forms a clade in our analyses with a sample of what has been referred to as T. major (now considered a subspecies of T. dubius). Consistent with other naturally occurring T. mirus populations, plastid sequences indicate that T. porrifolius was the maternal parent for both the AZ and OR collections. Microsatellite data are also consistent with local formation of T. mirus from co‐occurring populations of T. dubius and T. porrifolius in OR and AZ. As with sequence data, T. dubius from OR is distinct from other samples of T. dubius at microsatellite loci, contributing a unique signature to T. mirus from this location. It will be useful to include these additional geographical origins of T. mirus, particularly the more genetically distant sample from OR, in ongoing investigations of the genetic and genomic consequences of recent allopolyploidy. © 2012 The Linnean Society of London, Botanical Journal of the Linnean Society, 2012, 169 , 297–311. 相似文献
13.
MacLeod CD 《Evolution; international journal of organic evolution》2000,54(6):2171-2173
Beaked whales of the genus Mesoplodon are characterized by the presence of a single pair of sexually dimorphic tusks. Variation in the position and shape of these tusks was examined in four sympatric species and was found to be consistent with the hypothesis that these differences may have evolved to aid species recognition between sympatric and otherwise morphologically similar species of this genus. 相似文献
14.
Multiple independent formations of Tragopogon tetraploids (Asteraceae): evidence from RAPD markers 总被引:3,自引:0,他引:3
Polyploidy is widely recognized as a significant force leading to the formation of new plant species. Estimates of the number of angiosperm species with polyploid origins are as high as ≈ 50%; however, in spite of this prevalence, many aspects of polyploid evolution remain poorly understood. Recent studies have suggested that recurrent origins of polyploid species are the rule rather than the exception. The present study is one of only a few designed to quantify the number of independent origins of a polyploid species. The two tetraploid species Tragopogon mirus and T. miscellus (Asteraceae) arose within the past 50 years in the Palouse region of eastern Washington and adjacent northern Idaho. Previous work using morphology, cpDNA and rDNA restriction site analyses, allozymes, cytology, and flavonoid chemistry established that T. mirus had arisen at least five times, and T. miscellus at least twice, on the Palouse. To assess the frequency of multiple origins of these species more rigorously, seven populations of T. mirus and three populations of T. miscellus that were indistinguishable based on previous markers were surveyed using random amplified polymorphic DNA (RAPD) markers; populations of the diploid progenitor species from the same sites were also analysed. Each tetraploid population had a unique RAPD marker profile, suggesting that each population surveyed originated independently of the other populations in the region. Only two of the tetraploid populations combined the RAPD marker profiles of the diploid progenitors occurring at the same site. Both polyploid species, whose ranges and numbers have greatly increased since their formation in the early part of the twentieth century, have formed repeatedly on a local geographical scale and during a short time frame. Furthermore, each tetraploid species is spreading not primarily by dispersal of propagules from a single population of origin, but through repeated, independent polyploidization events that recreate the polyploid taxa. 相似文献
15.
As shown by morphological and molecular (ITS, nrLSU and tef1 sequences) evidence, the current concept of Myxarium nucleatum covers four species in the Nordic countries: M. cinnamomescens, M. hyalinum, M. nucleatum s.s. and M. populinum. These species are redescribed here, their nomenclature is discussed and all relevant names are typified. Exidia cartilaginea and E. villosa are typified and shown to be conspecific with the North American species E. candida. Based on morphological differences, E. cartilaginea is retained as a variety of E. candida. Exidia subrepanda is treated as a synomym of E. saccharina, and Heterochaete europaea as a synomym of E. thuretiana. 相似文献
16.
Richard J. A. Buggs 《Molecular ecology》2012,21(21):5159-5161
Inferences of whole genome duplication (WGD) events accompany the annotation of every newly sequenced plant genome, but much remains unknown about the evolutionary processes and pathways relating to WGD (Soltis et al. 2010). What ecological, biogeographical and genetic factors cause WGD to occur in nature? How does WGD affect gene expression? How do genomes evolve after WGD? New species that have arisen recently through WGD are good places to seek answers to such questions. These could be relatively common in nature, but reliably demonstrating their recent origin requires documentary evidence, which can be very hard to come by. Thus far, records of species introductions and meticulous botanizing have demonstrated six new natural allopolyploids in just four genera: Tragopogon miscellus and T. mirus, Senecio cambrensis and S. eboracensis, Spartina anglica and Cardamine schultzii (Abbott & Rieseberg 2012; Ainouche et al. 2009; Soltis & Soltis 2009). It is risky to generalize about a universal feature of plant evolution from such a small sample; more examples are needed, in different genera. It is therefore of considerable interest that Mario Vallejo‐Marin of University of Stirling has this year named a new allopolyploid species of monkey flower, Mimulus peregrinus, and presented evidence that it is <140 years old (Vallejo‐Marin 2012). This discovery is particularly timely as the monkey flower genus is developing rapidly as a model system for ecological genetics (Wu et al. 2008), and in the current issue of Molecular Ecology, Jennifer Modliszewski and John Willis of Duke University present new data showing high genetic diversity in another recently discovered monkey flower allopolyploid, M. sookensis (Modliszewski & Willis 2012). 相似文献
17.
Recent and recurrent polyploidy in Tragopogon (Asteraceae): cytogenetic, genomic and genetic comparisons 总被引:5,自引:0,他引:5
DOUGLAS E. SOLTIS PAMELA S. SOLTIS J. CHRIS PIRES ALES KOVARIK JENNIFER A. TATE EVGENY MAVRODIEV 《Biological journal of the Linnean Society. Linnean Society of London》2004,82(4):485-501
Tragopogon mirus Ownbey and T. miscellus Ownbey are allopolyploids that formed repeatedly during the past 80 years following the introduction of three diploids (T. dubius Scop., T. pratensis L. and T. porrifolius L.) from Europe to western North America. These polyploid species of known parentage are useful for studying the consequences of recent and recurrent polyploidization. We summarize recent analyses of the cytogenetic, genomic and genetic consequences of polyploidy in Tragopogon. Analyses of rDNA ITS (internal transcribed spacer) + ETS (external transcribed spacer) sequence data indicate that the parental diploids are phylogenetically well separated within Tragopogon (a genus of perhaps 150 species), in agreement with isozymic and cpDNA data. Using Southern blot and cloning experiments on tissue from early herbarium collections of T. mirus and T. miscellus (from 1949) to represent the rDNA repeat condition closer to the time of polyploidization than samples collected today, we have demonstrated concerted evolution of rDNA. Concerted evolution is ongoing, but has not proceeded to completion in any polyploid population examined; rDNA repeats of the diploid T. dubius are typically lost or converted in both allopolyploids, including populations of independent origin. Molecular cytogenetic studies employing rDNA probes, as well as centromeric and subtelomeric repeats isolated from Tragopogon, distinguished all chromosomes among the diploid progenitors (2n = 12). The diploid chromosome complements are additive in both allopolyploids (2n = 24); there is no evidence of major chromosomal rearrangements in populations of either T. mirus or T. miscellus. cDNA‐AFLP display revealed differences in gene expression between T. miscellus and its diploid parents, as well as between populations of T. miscellus of reciprocal origin. Approximately 5% of the genes examined in the allopolyploid populations have been silenced, and an additional 4% exhibit novel gene expression relative to their diploid parents. Some of the differences in gene expression represent maternal or paternal effects. Multiple origins of a polyploid species not only affect patterns of genetic variation in natural populations, but also contribute to differential patterns of gene expression and may therefore play a major role in the long‐term evolution of polyploids. © 2004 The Linnean Society of London, Biological Journal of the Linnean Society, 2004, 82 , 485–501. 相似文献
18.
D. A. Boakye C. Back G. K. Fiasorgbor A. P. P. Sib Y. Coulibaly 《Medical and veterinary entomology》1998,12(4):345-358
Abstract .During the decade from 1984 to 1993, nine species of the Simulium damnosum complex of blackflies (Diptera: Simuliidae) were identified from the area covered by the Onchocerciasis Control Programme. These were S. damnosum s.s., S. dieguerense, S. konkourense, S. leonense, S. sanctipauli, S. sirbanum, S. soubrense, S. squamosum, and S. yahense. Some of these species were found to consist of two chromosomal variant populations. These were S. konkourense‘Konkouré' and ‘Menankaya' forms, S. sanctipauli sensu stricto and‘Djodji' form, S. soubrense‘Chute Milo' and ‘Beffa' forms. The distribution of these twelve cytological taxa was assessed in relation to the two main vegetation zones of West Africa (forest and savanna), topography, river size and other factors. The range of each species was influenced by seasonal climatic changes in wind movement and river water level. The most widely distributed species were S. sirbanum and S. damnosum s.s., associated with savanna areas, recorded from all river basins. Simulium dieguerense was restricted mainly to Western Mali on the Rivers Bafing and Bakoye in the Senegal River basin. Simulium squamosum was identified from rivers draining mountainous areas in both the forest and savanna zones. Simulium yahense was found in small permanent rivers along a wide forested band parallel to the coast and was absent from the plains of Togo and Benin. Members of the S. sanctipauli subcomplex had restricted distributions except for S. sanctipauli s.s., which was widespread in large rivers of the forest zone from Sierra Leone to the Volta Lake in Ghana. Simulium soubrense‘Beffa' form occurred in Togo and Benin, S. soubrense‘Chutes Milo' form in Guinea, both ‘Konkouré' and ‘Menankaya' forms of S. konkourense occurred predominantly in Guinea and S. leonense in Sierra Leone. The relevance of the distribution maps and the importance of the data bank to vector control larvicidal operations are discussed. 相似文献
19.
Early life history of three pelagic‐spawning minnows Macrhybopsis spp. in the lower Missouri River
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Life‐history characteristics of age‐0 sturgeon chub Macrhybopsis gelida, shoal chub Macrhybopsis hyostoma and sicklefin chub Macrhybopsis meeki were compared using several methods. All Macrhybopsis species consumed mostly midge pupae, but M. meeki had the most general diet (Levins' index, B = 0·22) compared with M. hyostoma (B = 0·02) and M. gelida (B = 0·09). Morisita's diet overlap index among species pairs ranged from 0·62 to 0·97 and was highest between M. hyostoma and M. gelida. Daily ages estimated from lapilli otoliths for each species ranged from 15 to 43 days for M. gelida, 19 to 44 for M. hyostoma and from 16 to 64 days for M. meeki. Mean growth rates ranged from 0·79 mm day?1 for M. meeki to 1·39 mm day?1 for M. gelida. Mortality estimates indicated high daily survivorship rates for M. meeki (0·985), but could not be estimated for the other two species. Hatch date histograms were congruent with the belief that M. hyostoma and M. gelida spawn periodically from June to September. Macrhybopsis meeki, however, appeared to respond to a specific spawning cue as hatch dates were unimodal with a peak in July. These results fill a gap in current knowledge of these imperilled species that can be used to guide management decisions. 相似文献
20.
EVGENY V. MAVRODIEV IRSHAD NAWCHOO PAMELA S. SOLTIS DOUGLAS E. SOLTIS 《Botanical journal of the Linnean Society. Linnean Society of London》2008,158(3):391-398
Tragopogon kashmirianus (Asteraceae: Lactuceae) (2n = 24) was described based on collections from Kashmir. The tetraploid is morphologically similar to allotetraploid T. mirus from North America that has formed in western North America from the introduced T. dubius (2n = 12) and T. porrifolius (salsify; 2n = 12). Singh and Kachroo (1976 ) suggested that T. kashmirianus might have formed from the same diploid parental combination as T. mirus. To determine this, we investigated internal and external transcribed spacers (ITS, ETS) and five plastid regions of T. kashmirianus and species reported from Kashmir, northern India and neighbouring countries (T. badachschanicus, T. longirostris, T. porrifolius, T. pratensis, T. orientalis, T. subalpinus, T. trachycarpus, T. gracilis and T. dubius). Molecular data indicate that the parents of T. kashmirianus are not the European T. porrifolius and T. dubius. The exact parentage of T. kashmirianus is still unclear, but if it is an allotetraploid, at least one parent is a species native to Kashmir/India. Alternatively, it may represent an autopolyploid, again with the diploid parent native to Kashmir/India. We also found that ‘T. dubius’ from Kashmir is phylogenetically and morphologically distinct from collections of T. dubius from Europe and probably represents a previously unrecognized species. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 158 , 391–398. 相似文献