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1.
Limnologica ; 46: 1-8, 2014 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-24707064

RESUMO

Species distribution modelling, as a central issue in freshwater ecology, is an important tool for conservation and management of aquatic ecosystems. The brown trout (Salmo trutta) is a sensitive species which reacts to habitat changes induced by human impacts. Therefore, the identification of suitable habitats is essential. This study explores the potential distribution of brown trout by a species distribution modelling approach for Iran. Furthermore, modelling results are compared to the distribution described in the literature. Areas outside the currently known distribution which may offer potential habitats for brown trout are identified. The species distribution modelling was based on five different modelling techniques: Generalised Linear Model, Generalised Additive Model, Generalised Boosting Model, Classification Tree Analysis and Random Forests, which are finally summarised in an ensemble forecasting approach. We considered four environmental descriptors at the local scale (slope, bankfull width, wetted width, and elevation) and three climatic parameters (mean air temperature, range of air temperature and annual precipitation) which were extracted on three different spatial extents (1/5/10 km). The performance of all models was excellent (≥0.8) according to the TSS (True Skill Statistic) criterion. Slope, mean and range of air temperature were the most important variables in predicting brown trout occurrence. Presented results deepen the knowledge about distribution patterns of brown trout in Iran. Moreover, this study gives a basic background for the future development of assessment methods for riverine ecosystems in Iran.

2.
Zootaxa ; 5305(1): 1-69, 2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37518538

RESUMO

The current status of the ichthyofauna of Afghanistan is revised, and an updated checklist is presented. The confirmed fishes of Afghanistan comprise 121 species belonging to 11 orders, 22 families, and 68 genera. Among these, 18 species (14.9%) are alien, and 7 species (5.8%) are considered endemic to Afghanistan. The orders with the largest numbers of species in the ichthyofauna of Afghanistan are Cypriniformes (88 species), followed by Siluriformes (14 species), Anabantiformes (4 species), Acipenseriformes, Salmoniformes, and Cyprinodontiformes (3 species in each). At the family level, Cyprinidae have the greatest number of species (36 species; 29.8% of the total species), followed by Nemacheilidae (22 species), Leuciscidae (12 species), Danionidae (8 species), and Sisoridae (6 species). A total of 48 species previously reported from Afghanistan have been excluded from the checklist, either in the present study or in previous studies. According to the IUCN Red List criteria, among 121 listed fish species, 19 (15.7%) are in the threatened categories, with 4 (3.3%) CR, 6 (5.0%) EN, and 9 (7.4%) VU. Of the total number of taxa assessed, 5.0% (6 species) are NT and 51.2% (62 species) are LC. A total of 29 species are (24.0%) Not Evaluated (NE) and 5 species (4.1%) are classified as DD.


Assuntos
Peixes-Gato , Cyprinidae , Cipriniformes , Animais , Afeganistão , Peixes
3.
Sci Rep ; 13(1): 14347, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37658153

RESUMO

Co-occurring biodiversity and global heating crises are systemic threats to life on Earth as we know it, especially in relatively rare freshwater ecosystems, such as in Iran. Future changes in the spatial distribution and richness of 131 riverine fish species were investigated at 1481 sites in Iran under optimistic and pessimistic climate heating scenarios for the 2050s and 2080s. We used maximum entropy modeling to predict species' potential distributions by hydrologic unit (HU) occupancy under current and future climate conditions through the use of nine environmental predictor variables. The most important variable determining fish occupancy was HU location, followed by elevation, climate variables, and slope. Thirty-seven species were predicted to decrease their potential habitat occupancy in all future scenarios. The southern Caspian HU faces the highest future species reductions followed by the western Zagros and northwestern Iran. These results can be used by managers to plan conservational strategies to ease the dispersal of species, especially those that are at the greatest risk of extinction or invasion and that are in rivers fragmented by dams.


Assuntos
Ecossistema , Calefação , Animais , Biodiversidade , Clima , Planeta Terra , Peixes
4.
Zookeys ; (579): 157-81, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27110204

RESUMO

The molecular status of nine species of the genus Alburnoides from different river drainages in Iran and additionally by seven species from Europe was assessed. mtDNA COI gene sequences from freshly collected specimens and available NCBI data revealed four major phylogenetic lineages. Based on the results, a distinct taxon from the Cheshmeh Ali (Ali Spring), a Damghan River tributary in the endorheic Dasht-e Kavir basin, northern Iran, which is the closest sister to Alburnoides namaki (Namak Lake basin) + Alburnoides coadi (Nam River in the endorheic Dasht-e Kavir basin) is considered as a new species, Alburnoides damghani sp. n. It is distinguished from other Alburnoides species in Iran by a combination of character states including: a weakly-developed, variably-scaled, ventral keel from completely scaleless to completely scaled, a short snout with the tip of the mouth cleft on a level with the lower margin of the pupil or slightly lower, a small eye (eye horizontal diameter slightly to markedly less than interorbital width), commonly 8½ branched dorsal-fin rays, commonly 11-12½ branched anal-fin rays, 40-46(47) total lateral-line scales, 2.5-4.2 or 2.5-4.1 pharyngeal teeth, gill rakers short and widely spaced, 6-8 in total, 39-41 (commonly 40), total vertebrae, (19)20(21) abdominal vertebrae, 19-21 (most commonly 20) caudal vertebrae, abdominal vertebral region most commonly equal to or longer than caudal region, and most common vertebral formulae 20+20 and 21+19.

5.
Zookeys ; (374): 69-77, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24493966

RESUMO

The Iranian cave barb (Iranocypris typhlops Bruun & Kaiser, 1944) is a rare and endemic species of the family Cyprinidae known from a single locality in the Zagros Mountains, western Iran. This species is "Vulnerable" according to the IUCN Red List and is one of the top four threatened freshwater fish species in Iran. Yet, the taxonomic position of I. typhlops is uncertain. We examined phylogenetic relationships of this species with other species of the family Cyprinidae based on the mitochondrial cytochrome b gene. Our results show that I. typhlops is monophyletic and is sister taxon of a cluster formed by Garra rufa (Heckel, 1843) and Garra barreimiae (Fowler & Steinitz, 1956) within a clade that includes other species of the genus Garra. Based on previous molecular and morphological studies, as well as our new results, we recommend that I. typhlops should be transferred to the genus Garra Hamilton, 1822.

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