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1.
2.
Bahadzia setimana sp. nov. from South Andros, and B. obliqua sp. nov. from Cat Island, both in the Bahamas, are described. The recently described genus Bahadzia now contains five closely related taxa, each apparently confined to a single island or isolated group of islands, in a restricted area of the West Indies, ranging from Haiti in the south to the northern Bahamas.

The present discoveries show not only that low-salinity groundwaters of the West Indies have a marked degree of insular endemism, but that the high-salinity anchihaline habitats possess endemics in certain groups as well.

Current models which seek to explain the evolution of stygobionts on Atlantic Islands are reviewed critically and the most likely synthesis is provided.  相似文献   

3.
4.
《Journal of Natural History》2012,46(10):1503-1515
Neoathyreus androsensis n.sp., is described from Andros Is. in the Bahamas and from Cayo Coco, Cuba. The new species and four other previously described species, now known to occur in the West Indies, are briefly described, keyed and figured. One species, Neoathyreus lanei (Martínez) occurs in the Lesser Antilles and also in northern South America. The four other species occurring on either Cuba, the Bahamas, or Hispaniola are closely related to each other and somewhat less so to the Neoathyreus hamifer complex, known from Mexico and Central America. A minimum of two or three over-water dispersals by ancestral forms seem to be necessary to explain the current distributions of at least some of these West Indian species.  相似文献   

5.
Summary

The zoogeography of the Cayman Islands is discussed. Two species of Lutzomyia were found on Cayman Brac and they are described and their relation to other forms discussed. One is a Cuban species, or a close relative, and the other is allied to a Jamaican sand-fly.

A nematode parasite was found in one sand-fly.  相似文献   

6.
《Journal of Natural History》2012,46(33-34):2243-2256
The Indonesian island Sulawesi is well known for its fascinating fauna. Among the atyid and palaemonid freshwater shrimps described from Sulawesi are also a number of endemic species. In contrast, freshwater shrimps have never been reported from the nearby and smaller Peleng Island. Here we describe Caridina thomasi sp. nov. as a first record of an atyid freshwater shrimp from Peleng and compare it with atyids from Sulawesi and other localities. The new species is probably endemic to the island and shows some characters never described in the genus Caridina before. However, a molecular phylogeny of atyid shrimps from the Indo‐West Pacific based on mitochondrial DNA (16S) places C. thomasi within a clade of typical species of Caridina. We tentatively assign the new species to the genus Caridina and discuss the possibility of future changes in the classification of species in this genus.  相似文献   

7.
《Journal of Natural History》2012,46(17-20):1035-1046
Phylogenetic relationships between species of Lampetis (Spinthoptera) of North and Central America and the West Indies were analysed by cladistic methods, based on 65 characters from the external morphology and male genitalia. Eleven species of different generic groups of the subtribe Dicercina were considered as outgroups, including also species of Lampetis (Lampetis) and one South American species of L. (Spinthoptera). The monophyly of Lampetis (Spinthoptera) is supported by two synapomorphies, but this subgenus appears to be more closely related to species of Psiloptera rather than to Old World species of Lampetis (Lampetis), suggesting that Lampetis (Spinthoptera) may be segregated from Lampetis as a different genus. The species of Lampetis (Spinthoptera) from North and Central America and the West Indies do not represent a monophyletic taxon, because L. (S.) tucumana (South American outgroup) is nested within them. Comparison of these results with a previous panbiogeographic analysis indicate that several generalized tracks possess species from different clades, thus suggesting an ancient radiation of this taxon in Mesoamerica and the Mexican Transition Zone.  相似文献   

8.
Jamaica is the only island of the Greater Antilles where freshwater streams are not populated by representatives of the old lineage of freshwater crabs, the Pseudothelphusidae. Instead, a very diverse fauna of endemic sesarmid crabs inhabits freshwater and terrestrial habitats throughout the island, thereby showing complete independence from the sea. They have been reported thriving in bromeliad leaf axils, rock rubble, empty snail shells, caves and mountain streams. Otherwise, the Sesarmidae are typical inhabitants of soft‐sediment littoral habitats like marshes and mangroves. For many years, crabs from Jamaican mountains streams had been considered to belong to a single species, Sesarma bidentatum Benedict . However, recent morphological and molecular studies have shown that crabs from mountain streams of different regions of the island belong to different species. Consequently, four new crab species have been described over the last 10 years. In this study, we give evidence that freshwater streams in central Jamaica also host two different species of crabs. In streams draining to the north we exclusively found the species S. windsor Türkay and Diesel, , while streams draining to the south were inhabited by a closely related but undescribed species of crab. The southern species is here described as new and is referred to as Sesarma meridies sp. n. Morphological and molecular (12S and 16S mtDNA) evidence is provided that allows these two species of freshwater crabs from central Jamaica to be distinguished. The species richness of Jamaican endemic sesarmids thereby increases to 10, which makes the island unique in terms of its diversity of land‐dwelling crabs.  相似文献   

9.
A freshwater sponge is reported from St John, US Virgin Islands, the first report of a freshwater sponge from the West Indies. Study of the spicules and gemmules using light and scanning electron microscopy reveals characters indicative of a group of sponges generally considered to be closely related to, if not identical with, the cosmopolitan spongillid Ephydatia fluviatilis.  相似文献   

10.
《Journal of Natural History》2012,46(39-40):2567-2571
ABSTRACT

Biological invasions can have serious consequences for native communities. The Asian date mussel Arcuatula senhousia is an Asian species that has been accidentally introduced into coastal areas of North America, Oceania and the Mediterranean, with significant impact on local benthic communities. Here, we present the first record of this species in West Africa, after having found one live specimen in a mudflat off the island of Bubaque, in the Bijagós archipelago of Guinea-Bissau. Given the importance of the benthic communities for wintering shorebirds and local fisheries at this key West African wetland, and considering the invasive behaviour of Asian date mussels, we recommend further monitoring to confirm whether a self-maintaining population has settled in the area.  相似文献   

11.
The New Zealand flatworm, Artioposthia triangulata, and the Australian flatworm, Caenoplana alba, have become quite widespread in the British Isles since their introduction, probably in the early 1960s. They are considered as pest species since they eat earthworms and consequently may affect soil structure and fertility. The distribution of the two species has been recorded by two surveys: a Scottish survey between 1991 and 1993, and a national survey, MEGALAB WORMS, in March 1995. The latter was organized as part of National Science Week by BBC TV Tomorrow's World, The Daily Telegraph newspaper and the Office of Public Service and Science. Results of both surveys are presented as distribution maps of confirmed records. New Zealand flatworms are common and widespread in Northern Ireland and Central Scotland, and occur less commonly in other parts of Scotland, and in Northern England. There are a few scattered records from Southern England. The Scottish survey has resulted in retrospective distribution maps. Australian flatworms are widespread in South West England, and are found in several places in North West England. There are also records from South and North Wales, Northern Ireland and one from Southern Scotland. There were many false and negative reports. There are records of both species from the Republic of Ireland.  相似文献   

12.
The Neotropical genus Leptodactylus is currently represented by three species in the West Indies (Leptodactylus albilabris, Leptodactylus fallax and Leptodactylus validus). Based on morphological, acoustic and molecular evidence, we document the presence of a fourth species in the Caribbean region, Leptodactylus fragilis (Brocchi, 1877). The species was found at two localities in western Cuba, and molecular data suggest a northern South American origin, possibly Venezuela, for these populations. We discuss the potential invasive status of L. fragilis, based on its known distribution, relative abundance, behaviour and possible impacts on native species of Cuban amphibians.  相似文献   

13.
《Journal of Natural History》2012,46(23-24):3091-3102
The aim of this study was to create an inventory of the coral species which occur in the shallow waters around Rodrigues island. The stony corals of Rodrigues island have received limited study. Corals were recorded, photographed and collected from reef slopes and lagoons by scuba diving and snorkelling during October 2001. A collection of previously collected corals in Rodrigues was also studied. A total of 130 named species in 40 genera of hard corals (125 species in 37 genera of zooxanthellate Scleractinia) were found during the present survey, together with eight unidentified species; 47 species of coral were new records for Rodrigues, 37 of which were new reports for the southern Mascarene archipelago; 23 species represented extensions of their known ranges, including two species that were previously considered endemic to other areas. The number of species found is similar to that previously reported from Mauritius (134), and significantly more than reported in earlier studies of Rodriguan corals (up to 89 species). This also complements recent reports for Rodrigues (132 species) and Mauritius (163 species).  相似文献   

14.
The Canary Islands provide a difficult habitat for Simuliidae because of the scarcity of running water for the early stages, but the archipelago currently supports a fauna of six species (one other species formerly present is considered extinct). Breeding is confined to three of the seven islands (Gomera, La Palma, Tenerife), but once occurred also in Gran Canaria, an island that now lacks flowing streams. The taxonomic and faunal conclusions are based on a study of all available specimens, including material of early stages and reared adult flies collected by the author and aided by cytological data from the larval polytene chromosomes of several species. Twenty-one nominal species have at some time or another been reported from the Canaries, but, following this revision, only seven are recognized in the fauna (most past records being erroneous and based on misidentifications or false assumptions of endemicity); full synonymies clarify the old records in relation to modern nomenclature. All species belong to Simulium Latreille s.l., and keys are given to them in adult, pupal and larval stages. Three species are endemic (two newly described) and the other four common to the Palaearctic mainland. Some remarks are included on simuliid colonization and extinction in the islands.  相似文献   

15.
To date, 17 species of Laridae have been reported in Wyoming. Six of these species have know breeding populations in the state: the Ring-billed Gull ( Larus delawarensis ), California Gull ( Larus californicus ), Herring Gull ( Larus argentatus ), Caspian Tern ( Sterna caspia ), Forster's Tern ( Sterna forsteri ), and Black Tern ( Chlidonias niger ). Of these species, the California Gull is the most abundant and widespread. In 1984 approximately 7300 nests existed in Wyoming at six breeding locations consisting of 10 different colonies. In contrast, only small breeding populations have been discovered for the remaining five species. The Herring Gull is the most recent addition among Laridae know to nest in Wyoming. Likewise, two Ring-billed Bull colonies were recently found after not having been documented as breeding in the state for over 50 years. Although some nesting colonies are threatened by habitat loss and human disturbance, most seem secure at present. Limited nesting and foraging habitat precludes establishment of large breeding populations of most Laridae in the state.  相似文献   

16.
17.
《Journal of Natural History》2012,46(11):1597-1615
Over 8000 amphipods were examined from coastal (primarily intertidal) and anchialine pool habitats of Ascension Is. Twenty-seven species, of which 14 are undescribed, were identified. Comparison of species from Ascension with amphipods found in possible source areas suggests that most colonization of the island by these animals has been via the Benguela Current. Possible western Atlantic faunal contributions are significantly lower than for other marine taxa that have been studied at Ascension, all of which are generally characterized by having dispersive larval stages. The high proportion of apparently endemic species, which exceeds that described for amphipods of other oceanic islands, is probably due to both the island's isolation and incomplete faunal surveys in possible source areas. Amphipod species diversity is low, a probable consequence of the size, isolation, youth and low habitat variability of Ascension Is. Consistent with other Atlantic islands that have been studied, nestlers predominate (56% of the species), with tubicolous species (33%) of secondary importance and inquilines (11%) making only a minor contribution. Three species occur in the anchialine pool habitat. Rather unexpectedly, caprellid amphipods are absent.  相似文献   

18.
The crustaceans of the fresh waters of Bering Island and their link to the fauna of adjacent regions were studied. Based on original data and existing literature, the species composition of Cladocera and Copepoda was described. The compiled list includes 22 species of Cladocera and 30 species of Copepoda. In the original data, 35 species native to the Commander Islands were reported for the first time. Six species were newly reported in the Far East, and two were newly reported in Russia. The ecological peculiarities of several species and some biogeographical features of the freshwater zooplankton of the island are discussed. The main part of the fauna of the island form Holarctic widespread species (64.3%), another slightly smaller group of the fauna is comprised of Palaearctic species (20.1%), and the remainder comprise Nearctic (6.7%) and Beringian species (8.9%). Particular patterns in the distribution of freshwater zooplankton and the factors underlying the occurrence of these species on the island are considered.  相似文献   

19.
ABSTRACT

We describe two diminutive species of rattlesnakes (genus Crotalus) from small nearshore islands off the coast of Baja California in the western Gulf of California, Mexico. In order to test the hypothesis that some island populations represent cohesive species entities, we applied linear discriminant analysis and uniform validation procedures to multiple classes of intrinsic trait data. By using previously recognised species to establish a threshold for species recognition, we found that assignment of specimens to either new species was as probable as with other established rattlesnake species within the speckled rattlesnake (Crotalus mitchellii) complex. We also found that assignment of specimens from other island populations was not as probable as for the established species, and these populations are referable to C. pyrrhus. The species endemic to Piojo Island is most closely related to other island and mainland populations of C. pyrrhus whereas the species endemic to Cabeza de Caballo Island is apparently most closely related to C. angelensis, a nearby island endemic of large body size. However, patterns from both mitochondrial and nuclear phylogenies, and phenotypic variation, indicate that evolutionary trajectories of both of these species have been influenced by introgression from C. angelensis. We speculate that collective evidence based on contrasting patterns of nuclear and mitochondrial evolution supports a hybrid origin of the species from Cabeza de Caballo Island followed by exceptionally rapid mitochondrial evolution. Consistent with small body size, both species show a reduction in various scale counts relative to other species of the C. mitchellii species complex, suggesting that dwarfism is not simply a plastic response to insular conditions.

http://www.zoobank.org/urn.lsid:zoobank.org:pub:FBC8A11B-04A3-4231-85CA-3972DF5A42FF  相似文献   

20.
《Journal of Natural History》2012,46(16):2085-2117
As human demands for water have become more intense in modern times, the Canary Islands have become a difficult environment for all the macroinvertebrate fauna dependent upon running water for their survival; few permanent streams remain. Investigations on the simuliid (blackfly) fauna have shown, however, that at least six species exist in the archipelago, but that one, the endemic Simulium paraloutetense, known only from one site now destroyed, is possibly extinct. The paper presents cumulated data on distribution and material obtained over the past 33 years (since aquatic-stage specimens from breeding sites were first collected) with the aim of providing a baseline against which future studies of the Canarian simuliid fauna can be assessed. Revised identification keys for larvae and pupae are given to aid such monitoring. Remarks concerning each species include notes on chromosomal data when these are available. Comments are included on some aspects of the lotic habitats and island colonization.  相似文献   

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