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1.
Caecidotea williamsi Escobar-Briones & Alcocer (2002) is the first asellid described from a saline aquatic habitat in America, Alchichica crater-lake, Puebla, Central Mexico. No previous reports exist for asellid isopods from inland saline waters in America in spite of the extensive research undertaken so far on the continent. Differing from other asellids, C. williamsi inhabits saline waters (i.e. 8.5 g l−1) dominated by sodium, magnesium, chloride, and bicarbonate ions and markedly alkaline (pH 9.0 ± 0.1). Water temperature ranges from 14.5°C throughout the water column in winter and in the deep waters for the rest of the year, up to 20°C in the surface waters in summer. C. williamsi occurs in a depth range of surface to 30 m (lake’s maximum depth is 64 m), below which an anoxic layer is found during 9 months of the year. Generally it lives cryptically in tufa crevices and at shallower depths many inhabit empty trichopteran cases embedded within the tufa crevices. Some specimens are heavily covered by epizooic ciliates on the thoracic and abdominal segments of the exoskeleton and the pleopods. Data are presented on the diet, possible predators, saprobity and trophism, and regional distribution of C. williamsi. The continued survival of this unique isopod is threatened by anthropogenic desiccation of its habitat. Guest Editor: John M. Melack Saline Water and their Biota  相似文献   

2.
Dodson  Stanley I. 《Hydrobiologia》1985,126(1):75-79
A single population of an unusual ctenodaphnid was sampled in a shallow, turbid, temporary pond in eastern Utah in 1965. The animals resemble the African Daphnia (Ctenodaphnia) barbata, but show several morphological differences, and are therefore given the new name Daphnia (Ctenodaphnia) brooksi. Repeated efforts to collect this species since 1965 have failed, suggesting either the species is very rare, or the type population represented an instance of long-distance migration.  相似文献   

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4.
A new species of the Amphipoda (Gammarus desperatus) is described from North Spring in Roswell, Chaves County, New Mexico. Apparently this is the same species reported erroneously as G. fasciatus Say from nearby Lander Springbrook by Noel (1954).Supported in part by NSF Grants GB-2461 and GB-6477X to W. L. MinckleySupported in part by NSF Grants GB-2461 and GB-6477X to W. L. Minckley  相似文献   

5.
We describe three new species of forest robin in the genus Stiphrornis; two from West Africa and one from the Congo Basin. Each species represents a distinct phylogenetic lineage based on genetic analysis. In addition to genetic differentiation, each new species is diagnosable from other Stiphrornis lineages by morphology, and by plumage. One of the new species appears to be restricted to the Central and Brong-Ahafo Regions of Ghana, and another is restricted to Benin and the Central Region of Ghana. In Ghana, these two new species presumably come into contact with Stiphrornis erythrothorax (Western Region of Ghana and westward), and there is evidence that one of the new species has a distinguishably different song from erythrothorax. The distribution of the third new species is primarily on the south bank of the Congo River, near the city of Kisangani. Recognition of these species provides additional evidence that Afrotropical forests are harbouring substantial cryptic diversity, and that our knowledge of the drivers of this diversity remains poorly documented across the region.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:BF2A0BE6-1140-4EFF-9035-380D61AB03AE  相似文献   

6.
The new genus Mexicaphorura, and its type species Mexicaphorura guerrerensissp. n. are described from marine littoral sand. The new genus is similar to Sensilatullbergia Thibaud & Ndiaye, 2006 in having very big sensilla on sensorial organ of antennal segment III, but of different shape, the kind of postantennal organ, with simple vesicles in Mexicaphorura versus composed vesicles in Sensilatullbergia and formulae of the pseudocelli.  相似文献   

7.
Tigridia amatlanensis is described and illustrated as a new species from Mexico. It is recognized by its nodding flowers and its inner and outer tepals cirrhous and markedly dimorphic in length. It is most closely related toT. hallbergii subsp.hallbergii andT. meleagris. Other morphologically similar species areT. catarinensis andT. molseediana.  相似文献   

8.
Symplocos pachycarpa is described as new, and an illustration is provided. This species grows in cloud forests and oak-pine forests of Oaxaca and Guerrero, Mexico, and is most similar toS. citrea. A key is provided to distinguishS. pachycarpa from related Mexican species.  相似文献   

9.
The new benthic toxic dinoflagellate, Ostreopsis fattorussoi sp. nov., is described from the Eastern Mediterranean Sea, Lebanon and Cyprus coasts, and is supported by morphological and molecular data. The plate formula, Po, 3′, 7″, 6c, 7s, 5?, 2′′′′, is typical for the Ostreopsis genus. It differs from all other Ostreopsis species in that (i) the curved suture between plates 1′ and 3′ makes them approximately hexagonal, (ii) the 1′ plate lies in the left half of the epitheca and is obliquely orientated leading to a characteristic shape of plate 6″. The round thecal pores are bigger than the other two Mediterranean species (O. cf. ovata and O. cf. siamensis). O. fattorussoi is among the smallest species of the genus (DV: 60.07 ± 5.63 μm, AP: 25.66 ± 2.97 μm, W: 39.81 ± 5.05 μm) along with O. ovata. Phylogenetic analyses based on the LSU and internal transcribed spacer rDNA shows that O. fattorussoi belongs to the Atlantic/Mediterranean Ostreopsis spp. clade separated from the other Ostreopsis species. Ostreopsis fattorussoi produces OVTX‐a and structural isomers OVTX‐d and ‐e, O. cf. ovata is the only other species of this genus known to produce these toxins. The Lebanese O. fattorussoi did not produce the new palytoxin‐like compounds (ovatoxin‐i, ovatoxin‐j1, ovatoxin‐j2, and ovatoxin‐k) that were previously found in O. fattorussoi from Cyprus. The toxin content was in the range of 0.28–0.94 pg · cell?1. On the Lebanon coast, O. fattorussoi was recorded throughout the year 2015 (temperature range 18°C–31.5°C), with peaks in June and August.  相似文献   

10.
Astragalus mario-sousae is described from the central part of state of Nuevo León, Mexico. It differs fromAstragalus esperanzae by its habit, peduncles, pedicels, and fruits.
Resumen   Astragalus mario-sousae (Fabaceae: Galegeae), a new species from northeastern Mexico. Brittonia 57: 314–319. 2005.—Astragalus mario-sousae es propuesta como especie nueva. Se conoce solo de la porción central del estado mexicano de Nuevo León. Se presentan una descripción e ilustración. Difiere deAstragalus esperanzae por su hábito erecto, pedúnculos, pedicelos y frutos más cortos.
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11.
12.
Croton balsensis (Euphorbiaceae), a new species endemic to the Balsas Depression of southern Mexico, is described and illustrated. It occurs in the states of Guerrero, Morelos, and Puebla, growing in tropical deciduous forest at elevations from 450 to 1850m. It is best accommodated inCroton sect.Cascarilla. The Mexican species of this section are often quite similar, butC. balsensis is readily separated from related species by the possession of echinate ovaries and fruits.
Resumen  Se describe e ilustraCroton balsensis. Es endémica de la cuenca del río Balsas en el sur de México. Crece en los estados de Guerrero, Morelos y Puebla a altitudes de 450 a 1850 m en bosque tropical caducifolio. Pertenece aCroton sect.Cascarilla. Las especies mexicanas de esta sección por lo general son parecidas yC. balsensis se distingue por tener ovarios y frutos equinados.
  相似文献   

13.
Abstract

From the shelf and upper slope off the West Coast of the South Island of New Zealand, the following new taxa of Isopoda Anthuridea (Crustacea) are described: Kupellonura proberti n. sp. (Hyssuridae); Quantanthura pacifica n. sp., Haliophasma platytelson n. sp. and H. novaezelandiae n. sp. (Anthuridae) Albanthura stenodactyla n. gen. et sp., A. rotunduropus n. sp., Bullowanthura crebrui n. sp., Leptanthura tmncatitelson n. sp., L. exilis n. sp., L. profundicola n. sp., Paranthura longa n. sp., and Psittanthura egregia n. gen. et sp. (Paranthuridae). Most of these are blind, unpigmented species, adapted to life in deep water. Albanthura n. gen. is blind, has a single telsonic statocyst, short flagella of the antennae, a maxilliped with 3 palpal articles, and a triangular carpus on pereopods 4 to 7. Psittanthura n. gen. is also blind, with very unusual, enlarged subchelae of pereopods 1 and 2, a large, rectangular telson with a single statocyst; the maxillipedal palp is composed of 1 large and 1 small, distal article; a mandibular palp is absent.  相似文献   

14.
From a total of 104 species and 1741 individuals of Isopoda, the material from DIVA-1 (DIVersity of the Atlantic benthos) contained 364 specimens belonging to Desmosomatidae Sars, 1897. They are represented by 10 genera and 27 species. Most species (93%) are new to science. Four species are described in this study (Eugerdella theodori sp. nov., Desmosoma renatae sp. nov., Torwolia tinbiene sp. nov. and Momedossa longipedis sp. nov.). A discussion of the genera Desmosoma Sars, 1864, Momedossa Hessler, 1970 and Torwolia Hessler, 1970 is presented.  相似文献   

15.
Only four species of freshwater Nematomorpha (Gordiida) and one undetermined Gordius sp. are known from New Zealand. During recent surveys in the South Island we discovered a new species belonging to the genus Gordionus, a genus new to New Zealand. Scanning electron microscopic observations of seven collected specimens revealed that the species is clearly morphologically distinct from all other members of the genus and is characterised by the presence of an extensive row of large bristles on the ventral side of the posterior end in males. This row is much larger than in any known Gordionus species. Analysis of the mitochondrial CO1 gene and of the nuclear 18S rRNA gene showed that the new Gordionus specimens form a monophyletic clade, but with partly extensive internal genetic difference. This indicates that cryptic species might be present, for although there are minor variations in cuticular areoles, other morphological characters indicate little difference between specimens.

LSID urn:lsid:zoobank.org:pub:E6E436C0-9032-4D4B-B08C-1C7B6948291A  相似文献   


16.
Verbesina barrancae, a new species of Compositae (Heliantheae) from Jalisco, México, is described and illustrated. It is morphologically similar toVerbesina crocata but differs in characteristics of inflorescence, anthers, and achenes as well as in form of pollen, size and number of spinules, size of colpus transversalis, and index of polar area.  相似文献   

17.
Summary   Ceiba rubriflora Carv.-Sobr. & L. P. Queiroz, a new species of Malvaceae subfamily Bombacoideae from the State of Bahia, Brazil, is described and illustrated. It is considered to be endemic to calcareous outcrops in the valley of the Rio S?o Francisco, in the western region of the state. Notes on distribution, ecology and phenology are given. Relationships with related species are discussed and an addition to the key to species of Ceiba Mill. published by Gibbs & Semir (2003) are provided.  相似文献   

18.
Studying parallel evolution (repeated, independent evolution of similar phenotypes in similar environments) is a powerful tool to understand environment‐dependent selective forces. Surface‐dwelling species that repeatedly and independently colonized caves provide unique models for such studies. The primarily surface‐dwelling Asellus aquaticus species complex is a good candidate to carry out such research, because it colonized several caves in Europe. By comparing 17 functional morphological traits between six cave and nine surface populations of the A. aquaticus species complex, we investigated population divergence in morphology and sexual dimorphism. We found habitat‐dependent population divergence in 10 out of 17 traits, likely reflecting habitat‐driven changes in selection acting on sensory systems, feeding, grooming, and antipredator mechanisms. Sexual dimorphism was present in 15 traits, explained by sexual selection acting on male traits important in male–male agonistic behavior or mate guarding and fecundity selection acting on female traits affecting offspring number and nursing. In eight traits, the degree of sexual dimorphism was habitat dependent. We conclude that cave‐related morphological changes are highly trait‐ and function‐specific and that the strength of sexual/fecundity selection strongly differs between cave and surface habitats. The considerable population variation within habitat type warrants further studies to reveal cave‐specific adaptations besides the parallel patterns.  相似文献   

19.
Branchial bopyrids infesting porcellanid crabs from the Philippines were investigated based on intertidal collections made in 1999-2000. Crabs of the genus Petrolisthes collected from sites in the northern Philippines were examined and two parasite species were found. One new pseudionine species found infesting Petrolisthes sp. [cf. Petrolisthes asiaticus (Leach)] is described as Aporobopyrus galleonus (prevalence 6.1%); this species is distinguished from other members of the genus by a setose palp on the maxilliped of the females, barbula morphology, and male characters including the possession of pleopods. This represents the second described species of Aporobopyrus from the Philippines, and the first from porcellanid crabs. In addition, Pleurocrypta macrocephalaNierstrasz and Brender à Brandis, 1923 (originally described from Indonesia) was found infesting the same unidentified Petrolisthes sp. (prevalence 2.6%); this is the first report of the species from the Philippines.  相似文献   

20.
Morphological colour variation in Idotea baltica basteri Audouin, 1827 (Isopoda: Crustacea) is reported for the first time on populations from a brackish water lake (Kucukcekmece Lagoon) in Turkey. According to pigmentation characteristics, the isopods were described and sorted to ten different colour morphs which are named as maculata, maculata-lineata, uniformis, uniformis-lineata, immaculatum, immaculatum-lineata, nigrum, nigrum-lineata, albafusca, and albafusca-fasciatum. The similarity of the morphs was compared by defining digit codes to some of the visual pigmentation characteristics and calculating the Bray-Curtis similarity index of the colour morphs. The albafusca and albafusca-fasciatum forms were found to be the most similar to each other (similarity 96%), whereas immaculatum forms were considered the most different from maculata-lineata (similarity 50%). The morphs named maculata and maculata-lineata, having the highest abundance with 70%, belong to the most successful forms which may achieve crypsis by background matching in their living habitat in Kucukcekmece Lagoon which has sandy and rocky bottom surface area.  相似文献   

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