The examination of native habitats of newly introduced species is one of the factors that can provide information for predicting and preventing invasion success. In this study, we investigated the distribution patterns of a green macroalga, Codium fragile, in its native range in Korea. There were two distinct patterns for Codium spp. within their native habitat. In undisturbed communities, Codium species were members of the understory assemblage below the dominant canopy species. In disturbed habitats where native algae have been harvested for food, the activity created major gaps in the community structure where opportunistic algae expanded their abundance within the community. Codium fragile not only becomes a dominant canopy species in disturbed habitats, but it also colonizes new habitats such as fouling communities. Thus, the distribution patterns of Codium fragile in its native range suggests that it has the capability of taking advantage of disturbed habitats, which may help to explain why it has been such a successful invader in other regions of the world. One interesting finding was the lack of specialized sacoglossan herbivores associated with the Korean populations studied while such herbivores do feed on introduced populations in other regions, and may limit their distribution at some locations.

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In this study, a total of 120 fish specimens of common carp (Cyprinus carpio), were caught at four different stations in Shatt Al-Arab (Hareer, Garmat Ali, Al-Maqal and Abual-Khasib). The histological changes in the gills of fish were detected microscopically. Results show that the Shatt Al-Arab is polluted by some different sources of pollutants including power stations, paper industry, oil refineries, petrochemical industry, chemical fertilizer companies and the sewage system and overfishing and the application of pesticides. As a result of these analyses, histopathological changes in the gills of fish specimens, such as hyperplasia, loss of regular shape of secondary lamellae, separation of lamellar epithelium, clavate structure, atrophy of secondary gills lamellae, necrosis, dilation of lamellar capillaries, loss of secondary lamellae, fusion of secondary lamellae, edema, proliferation of cartilage in primary lamellae and curving of primary lamellae, were observed. The histopathological changes in fish gill samples from the Hareer region were much more prevalent than samples caught from other stations.

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The Shetland Islands, northern Scotland, have a highly active and diverse maritime environment, and local marine industries form an important part of the local economy. The potential for damage caused by non-native species is high. As part of an assessment of the current status of non-native species in Shetland, a series of rapid assessment surveys, coupled with a settlement panel monitoring programme, were carried out at 18 sites between May 2012 and October 2014. Eight non-native species were detected in our surveys, three of which (Corella eumyota Traustedt, 1882; Bugulina simplex Hincks, 1886; and Dasysiphonia japonica (Yendo) Kim, 2012) had not been previously recorded. Observations by SCUBA also reported the first UK record of Schizoporella japonica Ortmann, 1890 growing on natural substrate. A literature review revealed three additional non-native species that have been documented in Shetland but were not detected in our survey work. The results from this study highlight the speed at which non-native species can spread over regional scales, and that more active harbours contain greater numbers of non-native species, indicating the potential of hull fouling and ballast water exchange for transporting non-native species.

Specimens of the fiddler crab Uca (Paraleptuca) sindensis were collected from the intertidal zones of Khor Al-Zubair, Basrah, Iraq in 2009. A literature review on the distribution of this species revealed that this is the first report of U. (P) sindensis from the Iraqi coast and only the third country in which this species has been recorded. A note on the morphological features of this species and a photograph is provided to confirm the identification of the crab.

Citation: Yasser, A. G., F. Sheldon, and J. M. Hughes. 2018. Spatial distributions and environmental relationships of two species complexes of freshwater atyid shrimps. Ecosphere 9(8):Abstract. Knowledge of cryptic species distributions and their relationships with environmental factors may be extremely valuable for biodiversity conservation. In freshwater ecosystems, morphologically cryptic species often have different geographic distributions that can overlap to varying extents. The importance of differential species responses to environmental conditions in determining their spatial distributions is, however, unclear. Here, we evaluated the importance of species responses to environmental drivers, in particular the physicochemical factors, in the spatial distributions and environmental relationships of two shrimp species complexes Caridina indistincta Calman, 1926 and Paratya australiensis Kemp, 1917. We analyzed shrimp specimens from 89 sites in 17 catchments across South-East Queensland by sequencing a fragment of the mitochondrial cytochrome c oxidase subunit I gene (COI) to identify individuals. Furthermore, although there is evidence that morphologically the cryptic species of these shrimps differ very little, we made detailed morphological assessments to combine with molecular data, hoping to be able to distinguish among the species more easily and cheaply for future studies. There were significant morphological differences among the three cryptic species of the C. indistincta species complex, specifically in carapace length (cl), number of dorsal teeth (nDt), number of ventral teeth (nVt), teeth posterior to orbital margin (TPOM), and the calculated ratios A/rl, and rl/cl, while the two lineages of the P. australiensis species complex differed in the number of dorsal teeth (nDt) and the calculated ratios of A/rl, rl/cl, and rh/ch. To determine the importance of species responses in explaining the spatial distribution of cryptic species based on the species-variables relationships, a redundancy analysis (RDA) was used to summarize these relationships. This ordination analysis showed distinct differences among cryptic species in their correlation with water quality variables and elevation. C. indistincta sp. B and C. indistincta sp. D were significantly associated with elevation and dissolved oxygen range, respectively. As well, P. australiensis lineages 4 and 6 were significantly correlated with elevation and conductivity, respectively. Overall, our results demonstrated the advantage of using analyses of biotic and abiotic variables as a valid approach for defining species responses to abiotic factors in cryptic species of atyid freshwater shrimps.

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