241 research outputs found
Ecological observations on the caddisflies (Insecta : Trichoptera) from Trinidad and Tobago (W. Indies)
Le travail présente les résultats écologiques d'une campagne de récoltes intensives de trichoptères dans un nombre de localités à Trinidad et Tobago (les résultats taxonomiques, faunistiques et biogéographiques sont publiés ailleurs ... Un aperçu général est donné des localités où les récoltes ont été réalisées, surtout dans les bassins du Northern Range de Trinidad ... mais aussi au Trinidad central et méridional et à Tobago. Des notes autoécologiques, mais aussi éthologiques et se rapportant au "trophic guilds" sont présentées pour 42 espèces (un peu plus de 50 espèces étant actuellement connues pour les deux îles
Four new stygobitic cirolanids (Crustacea: Isopoda) from the Caribbean: with remarks on intergeneric limits in some cirolanids
Four new stygobitic and troglomorphic cirolanids are described from various parts of the Caribbean. Cirolana (C.) troglexuma n. sp. is described from a cave on one of the Exuma Cays, Bahamas; two subgenera are recognized in g.Cirolana: sg. Cirolana including troglexuma as only presently know stygobitic species, and sg. Anopsilana equally well represented by subterranean and by epigean species. Haptolana bowmani n. sp. and H. belizana n. sp. inhabit caves of Yucatan and Belize, respectively; interestingly they are both abundantly different from the Cuban species of this stygobenthic genus, showing more similarity with the species from Somalia and W. Australia. Jamaicalana pleoscissa n.g. n. sp. was discovered in a cave from Jamaica; the new genus has affinities with Anopsilana and Bahalana, but a combination of characters -some of them highly original- renders definition of a new genus necessary. Bahalana mayana Bowman should be removed from that genus, whereas Dodecalana yagerae Carpenter is an interesting species of Bahalana
Two new stygobitic species of Cirolanidae (Isopoda) from deep cenotes in Yucatan
Haptolana yunca n. sp. is the 6th described species of an entirely hypogean-adapted genus. Cirolana (Anopsilana) yucatana n. sp. is the 9th described stygobitic and troglomorphic species in this subgenus. Both were discovered by diving in deep waters of cenotes in the Yucatan peninsula, a region from which five stygobitic cirolanid species were known. Jamaicalana BOTOSANEANU & ILIFFE, 1997, is synonymized with Cirolana (Anopsilana)
Islands beneath islands: phylogeography of a groundwater amphipod crustacean in the Balearic archipelago
<p>Abstract</p> <p>Background</p> <p>Metacrangonyctidae (Amphipoda, Crustacea) is an enigmatic continental subterranean water family of marine origin (thalassoid). One of the species in the genus, <it>Metacrangonyx longipes</it>, is endemic to the Balearic islands of Mallorca and Menorca (W Mediterranean). It has been suggested that the origin and distribution of thalassoid crustaceans could be explained by one of two alternative hypotheses: (1) active colonization of inland freshwater aquifers by a marine ancestor, followed by an adaptative shift; or (2) passive colonization by stranding of ancestral marine populations in coastal aquifers during marine regressions. A comparison of phylogenies, phylogeographic patterns and age estimations of clades should discriminate in favour of one of these two proposals.</p> <p>Results</p> <p>Phylogenetic relationships within <it>M. longipes </it>based on three mitochondrial DNA (mtDNA) and one nuclear marker revealed five genetically divergent and geographically structured clades. Analyses of cytochrome oxidase subunit 1 (<it>cox1</it>) mtDNA data showed the occurrence of a high geographic population subdivision in both islands, with current gene flow occurring exclusively between sites located in close proximity. Molecular-clock estimations dated the origin of <it>M. longipes </it>previous to about 6 Ma, whereas major cladogenetic events within the species took place between 4.2 and 2.0 Ma.</p> <p>Conclusions</p> <p><it>M. longipes </it>displayed a surprisingly old and highly fragmented population structure, with major episodes of cladogenesis within the species roughly correlating with some of the major marine transgression-regression episodes that affected the region during the last 6 Ma. Eustatic changes (vicariant events) -not active range expansion of marine littoral ancestors colonizing desalinated habitats-explain the phylogeographic pattern observed in <it>M. longipes</it>.</p
Longitudinal river zonation in the tropics: examples of fish and caddisflies from endorheic Awash river, Ethiopia
Primary Research PaperSpecific concepts of fluvial ecology are
well studied in riverine ecosystems of the temperate
zone but poorly investigated in the Afrotropical
region. Hence, we examined the longitudinal zonation
of fish and adult caddisfly (Trichoptera) assemblages
in the endorheic Awash River (1,250 km in length),
Ethiopia. We expected that species assemblages are
structured along environmental gradients, reflecting
the pattern of large-scale freshwater ecoregions. We
applied multivariate statistical methods to test for differences in spatial species assemblage structure and
identified characteristic taxa of the observed biocoenoses
by indicator species analyses. Fish and
caddisfly assemblages were clustered into highland
and lowland communities, following the freshwater
ecoregions, but separated by an ecotone with highest
biodiversity. Moreover, the caddisfly results suggest
separating the heterogeneous highlands into a forested
and a deforested zone. Surprisingly, the Awash
drainage is rather species-poor: only 11 fish (1
endemic, 2 introduced) and 28 caddisfly species (8
new records for Ethiopia) were recorded from the
mainstem and its major tributaries. Nevertheless,
specialized species characterize the highland forests, whereas the lowlands primarily host geographically
widely distributed species. This study showed that a
combined approach of fish and caddisflies is a
suitable method for assessing regional characteristics
of fluvial ecosystems in the tropicsinfo:eu-repo/semantics/publishedVersio
Etude d'une faunule madicole de Guadeloupe : compléments à la connaissance des Trichoptères (Trichoptera) de l'Ile
L'étude de la faune madicole est fort peu avancée aux tropiques. En Guadeloupe, l'étude d'un vaste habitat madicole typique dans le massif de la Soufrière a été entreprise. La faune comporte un nombre d'éléments eumadicoles ou au moins madicophiles : Hydracariens, Diptères, et surtout Trichoptères. Parmi les 10 espèces de Trichoptères appartenant à ces catégories, plusieurs sont soit des nouveautés pour la faune de la Guadeloupe, soit représentées par des [math] pas encore décrites au niveau de l'espèce pour être nommées ; le cas le plus remarquable est celui de la stricte coexistence de deux espèces de Byrsopteryx, dont une décrite comme nouvelle, et qui se distinguent par la coloration des ailes et par la structure des tergites abdominaux, leurs genitalia [math] semblant être identiques. Les Trichoptères de 4 cours d'eau auparavant non échantillonnés et appartenant à des zones différentes ont été collectés à la lumière UV, ce qui permet certaines comparaisons. La description de deux espèces endémiques pour la Guadeloupe est complétée. 47 espèces de Trichoptères sont actuellement connues de Guadeloupe
- …