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1.
Four new foliicolous lichen species are described from the Ivory Coast (Tropical West Africa): Bapalmuia ivoriensis sp. nov., Chroodiscus africanus sp. nov., C. verrucosus sp. nov., and Lasioloma inexspectatum sp. nov. In addition, the new combination Calenia inconspicua comb, nova [Bas.: Heterothecium inconspicuum] is introduced. Lasioloma inexspectatum is the first species in the genus characterized by transversely septate ascospores and provides additional evidence for phylogenetic lines regarding the evolution of ascospore types in the lichen family Ectolechiaceae. In addition, 61 new records for the Ivory Coast and seven for Guinea are presented, increasing the number of species known in these areas to 161 and 124, respectively. Five species are new for tropical Africa, and six new for the Paleotropics. Further taxonomical and ecogeographical notes on the foliicolous lichen flora of tropical West Africa are provided.  相似文献   

2.
We examined the reproductive biology and estimated life history parameters for female shortspine thornyhead, Sebastolobus alascanus, and longspine thornyhead, S. altivelis, from histological samples prepared from specimens collected from both Alaska and the West Coast of the United States. Both species spawn pelagic gelatinous egg masses, although timing differs between taxa and locations. Shortspines spawn between April and July in Alaska and between December and May along the West Coast. Longspines spawn between January and April along the West Coast. Length at 50% maturity differed between species and areas, with shortspines at 21.48cm in Alaska and 18.19cm on the West Coast, and longspines at 17.83cm on the West Coast. We used the gonadosomatic index to estimate instantaneous rates of natural mortality (M). Values of M differed little between species and areas despite substantial differences in temperature and dissolved oxygen concentrations. Estimates for shortspines from both Alaska and the West Coast ranged between 0.013 and 0.017, while longspines from the West Coast showed an M value of 0.015. Such low estimates of M suggest Sebastolobus are extremely long-lived.  相似文献   

3.
4.
The gills of two species of Siluriformes, Heterobranchus longifilis and H. isopterus collected from the Rivers Agnéby and Bia in the Ivory Coast (West Africa) revealed the presence of seven new species of Quadriacanthus Paperna, 1961 (Monogenea: Ancyrocephalidae). The following parasites are described: Quadriacanthus longifilisi n. sp., Q. thysi n. sp., Q. ayameensis n. sp., Q. agnebiensis n. sp., Q. simplex n. sp., Q. gourenei n. sp. and Q. macrocirrus n. sp.  相似文献   

5.
The three subspecies of Spotted Owl (Northern, Strix occidentalis caurina; California, S. o. occidentalis; and Mexican, S. o. lucida) are all threatened by habitat loss and range expansion of the Barred Owl (S. varia). An unaddressed threat is whether Barred Owls could be a source of novel strains of disease such as avian malaria (Plasmodium spp.) or other blood parasites potentially harmful for Spotted Owls. Although Barred Owls commonly harbor Plasmodium infections, these parasites have not been documented in the Spotted Owl. We screened 111 Spotted Owls, 44 Barred Owls, and 387 owls of nine other species for haemosporidian parasites (Leucocytozoon, Plasmodium, and Haemoproteus spp.). California Spotted Owls had the greatest number of simultaneous multi-species infections (44%). Additionally, sequencing results revealed that the Northern and California Spotted Owl subspecies together had the highest number of Leucocytozoon parasite lineages (n = 17) and unique lineages (n = 12). This high level of sequence diversity is significant because only one Leucocytozoon species (L. danilewskyi) has been accepted as valid among all owls, suggesting that L. danilewskyi is a cryptic species. Furthermore, a Plasmodium parasite was documented in a Northern Spotted Owl for the first time. West Coast Barred Owls had a lower prevalence of infection (15%) when compared to sympatric Spotted Owls (S. o. caurina 52%, S. o. occidentalis 79%) and Barred Owls from the historic range (61%). Consequently, Barred Owls on the West Coast may have a competitive advantage over the potentially immune compromised Spotted Owls.  相似文献   

6.
This is an historical paper examining the scientific background of George Ledyard Stebbins, Jr. (b. 1906), one of the foremost botanists of this century and one of the architects of the evolutionary synthesis, the intellectual event that brought together genetics and selection theory in the interval between 1920 and 1950. It considers his scientific influence and research, beginning with his Harvard education in 1924 and ending in 1950 with the publication of his book Variation and Evolution in Plants. The paper also more broadly assesses the contributions of other botanists to the evolutionary synthesis, including discussion of the work of Edgar Anderson (1897-1967) and others. It also traces the larger historical patterns of American botany, which saw a shift from East Coast botany as exemplified by Harvard botany, to West Coast botany, as exemplified by California botany.  相似文献   

7.
Drift collections of pupal exuviae from 2nd–5th order streams of the Guanacaste National Park in Northwest Costa Rica and from 3rd–6th order streams of the West African countries of Guinea, Ivory Coast, Sierra Leone and Togo have revealed high community (alpha) and regional (beta) levels of species diversity.Samples have been processed from 13 streams of the Guanacaste N. P. including two, Quebrada Las Yeguitas (2 stations) and Rio Tempisquito, for which year-long series were available. A total of 266 species level taxa have been recognized from these streams and are distributed over the higher taxa as follows: Chironomini-73, Pseudochironomini-4, Tanytarsini-55, Orthocladiinae-92, Macropelopiini-5 and Pentaneurini-37. The two sites on the Q. Las Yeguitas have a combined total of 216 species, and together with R. Tempisquito a total of 238 species. The single richest sample (Q. Las Yeguitas, Orosi station, 1990-Jan.-9) contained 102 species.Samples have been processed from 31 West African Streams which, for the most part, are represented by single samples. A total of 299 species level taxa have been recognized from these streams which are distributed over the higher taxa as follows: Chrinomini-139, Tanytarsini-62, Orthocladiinae-56, Coelotanypodini-2, Macropelopiini-3 and Pentaneurini-37. The single largest collection, containing 175 species, was taken from the Upper Dion River, a 6th order stream in the Upper Niger basin of the Guinean highlands.The compositions of the two regional faunas show similarities in two general features: they are both taxonomically narrow (few subfamilies and tribes) and taxonomically deep (many closely related genera, often with a relatively large number of closely related species). The high alpha diversity values require an ecological explanation, most probably along the axes of resources (time, space and food). The high regional diversities require an historical explanation. It is proposed that great climatic variation during the Pleistocene coupled with great geographic alteration of the connection between North and South America may be responsible for both the taxonomic narrowness and depth seen in the chironomid faunas of West Africa and Costa Rica.  相似文献   

8.
Ceratitis fasciventris, C. anonae and C. rosa form a complex of economically important fruit fly pests infesting a variety of crops in African countries. Hitherto only adult males of these species can be distinguished easily by morphological characters. Other stages cannot, and for some taxa the taxonomic interpretation and species boundaries remain unclear. In order to clarify phylogenetic relationships and taxonomic status of these species, sequences of mitochondrial (16S, COI, ND6) and nuclear markers (period, ITS1) were analysed in specimens of the three morphospecies throughout the distribution of the complex. Maximum likelihood trees did not recover monophyletic groups corresponding to the morphospecies. Conversely, ND6 and COI divided West African C. fasciventris specimens in two consistent and bootstrap supported clades, involving specimens from Benin and from Mali/Ivory Coast, while the nuclear gene fragments per and ITS1 recovered a well-supported clade corresponding to C. fasciventris from Kenya/Uganda. Hence, the phylogenetic relationships and taxonomic interpretation of the complex appear more intricate than previously hypothesised. The current molecular data do not allow to identify C. fasciventris, C. anonae and C. rosa as distinct phylogenetic species but rather suggest that the morphospecies C. fasciventris is itself a complex of cryptic taxa.  相似文献   

9.
The stomach contents of 1522 adult seals ( Arctocephalus pusillus pusillus ) and 673 pups, which were collected around the West and South Coasts of Southern Africa, were examined and cephalopod prey identified. About 20 cephalopod species (some identifications were uncertain) were found in the stomachs, of which only six were significant: Loligo vulgaris reynaudii. Sepia spp., Octopus sp., Todaropsis eblanae, Todarodes angolensis and Ocythoe tuberculata. This list suggests that A. pusillus feeds exclusively on the continental shelf, frequently on or near the bottom. Among adults, cephalopod prey varied in importance around the coast. It was most important on the South Coast of South Africa where it comprised 35.0% of the weight of all prey, of which L. v. veynaudii constituted about 88%. On the West Coast cephalopods comprised about 26.6% by weight of all prey, and Octopus sp. predominated, whereas in Namibian waters cephalopods were least important, constituting only 3.4% by weight of all prey, with Todarodes angolensis and Octopus sp. being most significant. Among pups (aged 8–10 months) in the Lüderitz (Namibia) area, cephalopods were about 16.9% of prey by weight, of which Ocythoe tuberculata , small Sepia spp. and Octopoda were most important.  相似文献   

10.
To better understand the population substructure of African Americans living in coastal South Carolina, we used restriction site polymorphisms and an insertion/deletion in mitochondrial DNA (mtDNA) to construct seven-position haplotypes across 1,395 individuals from Sierra Leone, Africa, from U.S. European Americans, and from the New World African-derived populations of Jamaica, Gullah-speaking African Americans of the South Carolina Sea Islands (Gullahs), African Americans living in Charleston, South Carolina, and West Coast African Americans. Analyses showed a high degree of similarity within the New World African-derived populations, where haplotype frequencies and diversities were similar. Phi-statistics indicated that very little genetic differentiation has occurred within New World African-derived populations, but that there has been significant differentiation of these populations from Sierra Leoneans. Genetic distance estimates indicated a close relationship of Gullahs and Jamaicans with Sierra Leoneans, while African Americans living in Charleston and the West Coast were progressively more distantly related to the Sierra Leoneans. We observed low maternal European American admixture in the Jamaican and Gullah samples (m = 0.020 and 0.064, respectively) that increased sharply in a clinal pattern from Charleston African Americans to West Coast African Americans (m = 0.099 and 0.205, respectively). The appreciably reduced maternal European American admixture noted in the Gullah indicates that the Gullah may be uniquely situated to allow genetic epidemiology studies of complex diseases in African Americans with low European American admixture.  相似文献   

11.
Wildlife populations of conservation concern are limited in distribution, population size and persistence by various factors, including mortality. The fisher (Pekania pennanti), a North American mid-sized carnivore whose range in the western Pacific United States has retracted considerably in the past century, was proposed for threatened status protection in late 2014 under the United States Endangered Species Act by the United States Fish and Wildlife Service in its West Coast Distinct Population Segment. We investigated mortality in 167 fishers from two genetically and geographically distinct sub-populations in California within this West Coast Distinct Population Segment using a combination of gross necropsy, histology, toxicology and molecular methods. Overall, predation (70%), natural disease (16%), toxicant poisoning (10%) and, less commonly, vehicular strike (2%) and other anthropogenic causes (2%) were causes of mortality observed. We documented both an increase in mortality to (57% increase) and exposure (6%) from pesticides in fishers in just the past three years, highlighting further that toxicants from marijuana cultivation still pose a threat. Additionally, exposure to multiple rodenticides significantly increased the likelihood of mortality from rodenticide poisoning. Poisoning was significantly more common in male than female fishers and was 7 times more likely than disease to kill males. Based on necropsy findings, suspected causes of mortality based on field evidence alone tended to underestimate the frequency of disease-related mortalities. This study is the first comprehensive investigation of mortality causes of fishers and provides essential information to assist in the conservation of this species.  相似文献   

12.
Accumulation of poliovirus Lsc-2ab by West Coast oysters was determined by using a stationary seawater system, and depuration was determined by using both stationary and free-flow systems. Results indicate that these shellfish have the same pattern of accumulation and localization of viruses as do East Coast species. However, uptake appeared to occur more rapidly than described for East Coast shellfish. There appeared to be a gradual diffusion of virus from the digestive area into the body. Depuration was found to occur more rapidly and completely under free-flow conditions than in a stationary system.  相似文献   

13.
In this study a new species of nematode, Iheringascaris goai n. sp., is reported from two fish hosts, including silver whiting, Sillago sihama, and spotted catfish, Arius maculatus, caught off the Central West Coast of India at Goa. The new species can be differentiated morphologically from I. inquies, the most closely related species collected from cohabiting marine fish. The distinguishing characteristics are distinct cuticular striations, a unilateral excretory system, the presence of dentigerous ridges on the inner margin of the lips and the ratio of oesophagus to body length. In males, the ratio of spicules to body length is higher and the number of pre-anal papillae is less in comparison to those in I. inquies. In addition, the tail curves ventrad in males, while in females, the vulva is post-equatorial. The sequence alignment of 18S rDNA and cytochrome c oxidase subunit I with sequences of known species selected from the same superfamily shows a significant difference. The morphological and molecular differences reported here can, therefore, be used to assign the specimen to a new species.  相似文献   

14.
Six colour phases are currently known in the genus Dasypeltis in West Africa, three in the D. scabra complex and three in the D. fasciata complex. Molecular phylogenetic analysis reveals that all correspond to distinct species. D. parascabra sp. nov. is described from wet savannah areas of Guinea and Ivory Coast. D. latericia is given full specific rank. The validity of D. sahelensis, D. gansi and D. confusa – three species recently described on the basis of colour pattern and biogeography – is confirmed. D. fasciata is confined to rain forest areas of West and Central Africa. D. scabra is absent from West Africa.  相似文献   

15.
The rare Johnston’s Genet (Genetta johnstoni) is one of the least known small carnivores inhabiting the West African rain forest. Some newly discovered specimens collected from the field (Guinea and Ivory Coast) and several rediscovered specimens resulting from reinvestigating collections, have permitted us to reconsider the distribution of the species. Coupled with a bibliographic review and a census of specimens kept in public collections, a reassessed distribution map is proposed, extending the previous estimated range 400 km to the West (Kolenté Plates, Guinea) and more than 600 km to the East (Tarkwa, Ghana). The majority of collected specimens have come from the inland forests of northern Liberia and south‐eastern Guinea, while the surroundings of Mt. Nimba also support numbers of this species. We suggest that the supposed restriction of G. johnstoni to rain forest be re‐evaluated because a specimen was collected in a region of moist woodlands and savannah (Kolenté Plateau). With regard to these new distributional data, conservation implications for the whole Upper Guinean block population are discussed.  相似文献   

16.
The whiting ( Merlangius merlangus ) is an important commercial species from the West Coast of Scotland. This paper describes the distribution, abundance, age composition and growth of juvenile whiting which are found in the inshore areas and sea lochs. No spawning was observed in the areas and it is assumed there was an active migration of whiting from the open sea. They were first caught by the bottom trawl in July, reached maximum abundance in November and December and thereafter declined in numbers until few remain by early summer. An exception to this occurs in Loch Etive and possible explanations for the fact that whiting tend to remain for longer periods and grow at a slower rate in this loch are discussed.  相似文献   

17.
Zuccarello and West (2003) reported on the phylogenetic diversity of algae identified as Bostrychia radicans (Montagne) Montagne and B. moritziana (Sonder ex Kützing) J. Agardh from around the world. They showed that the species complex consisted of seven distinct lineages, of which two lineages were common on the East Coast of the USA and eastern Gulf of Mexico. The distribution of haplotypes within these lineages on the East Coast of the USA showed a general north–south distribution. One haplotype of lineage 5 (B) was mostly collected in northern areas, while the other common haplotype (C) was more southerly in distribution. Samples in lineage 6 (haplotype D) were not found north of Sapelo Island, Georgia. Increased sampling from the eastern USA over 5 years later has revealed an altered pattern. Haplotype D is distributed in North Carolina and is common in some populations. Haplotype C is rare or absent in many sampled populations. Haplotype B is only observed in the northern sampled sites on both sides of the Florida peninsula. This disjunct distribution agrees with geological scenarios for a strait between the western Gulf of Mexico and southern Georgia in the Miocene/Pliocene, which closed in the late Pliocene. This paper highlights the importance of increased sampling to determine phylogeographic patterns and hypotheses of dispersal scenarios in algae.  相似文献   

18.
The new species Caesia sabulosa Boatwr. and J.C.Manning from deep sands along the West Coast of South Africa and sandy flats in the Cederberg and Bokkeveld Escarpment is described. It is distinguished by its extensively branched rhizome resulting in a robust, clump-forming habit, and unique ‘palisade’ root system of closely packed, hard, vertical roots; mostly larger flowers; erect fruiting pedicels; and details of the seed testa sculpturing.  相似文献   

19.
The new species, Annesorhiza calcicola Magee and J.C. Manning, is described. It is known only from a few limestone outcrops around Jacobsbaai on the Saldanha Peninsula on the West Coast of South Africa. The species differs from all others in the genus in its small stature (inflorescence less than 0.3 m and leaves less than 150 mm long), the hysteranthous, pilose leaves which are completely absent at flowering (in the other species dead or dying at flowering and usually glabrous), the greyish-black, pilose inflorescence (yellowish-brown and glabrous in the other species) and the smaller homomericarpic fruit less than 5 mm long.  相似文献   

20.
Stable isotope analysis (δ18O and δ13C) of otolith aragonite was used to infer ontogenetic patterns of movement, delineate sub-population structure, and determine the mixing of Southern Garfish (Hyporhamphus melanochir) in South Australian waters. Adult garfish from the 2+ age class were collected from three sites within each of six regions along the South Australian coast: Northern Gulf St. Vincent, South West Gulf St. Vincent, Kangaroo Island, Northern Spencer Gulf, South West Spencer Gulf and the West Coast of Eyre Peninsula. Significant spatial variation was detected in mean δ18O and δ13C values among sites within regions and as a function of fish age. Salinity, rather than sea surface temperature, appeared to account for regional variation in δ18O, whereas variation in diet and metabolic processes were suggested to account for observed differences in δ13C. Otolith oxygen and carbon stable isotope values indicated that the South Australian Southern Garfish fishery is comprised of multiple, regional, population components that persist through time. Both the West Coast and Northern Spencer Gulf regions constitute distinct population components that exhibit little inter-regional mixing and therefore may be considered as discrete management units. The South West Spencer Gulf region may also be considered a separate population component, however, its level of connectivity with Gulf St. Vincent is uncertain. With the exception of juvenile garfish from Kangaroo Island, there was no clear regional separation within Gulf St. Vincent.  相似文献   

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