Identification of Three Common Loliginidae Squid Species in the South China Sea by Analyzing Hard Tissues with Geometric Outline Method

The hard tissues of squid can provide important information for species identification. In this study, we used statolith and beak to identify three squid species including Uroteuthis duvaucelii, Loliolus beka, and U. edulis in the South China Sea. Because of the highly overlapping habitat and similar body morphology of the three squid species, we explored four different ways to identify them, by using statolith, upper beak, lower beak and a combination of statolith and beak. An outline geometric morphometric method and stepwise discriminant analysis were used to evaluate the most suitable method for the identification. We found that the combination of statolith and beak had the highest cross validation rate that was 75.0%, 87.5% and 88.7% for U. duvaucelii, L. beka and U. edulis, respectively. Using two beaks had similar results and the lowest cross validation rate was 60.0%, 50.0%, and 73.7% for the upper beak, 46.9%, 58.5% and 75.3% for the lower beak of U. duvaucelii, L. beka and U. edulis, respectively. Analyzing with the statolith had moderate cross validation which was 72.2%, 80.0%, and 87.7% for U. duvaucelii, L. beka and U. edulis, respectively. From the results it is suggested when the entire body of a squid is available, a combination of statolith and beak should be used for the identification. When only one hard tissue is available, species identification can be subjected to large errors.

Morphological and molecular evidence supports the occurrence of a single species of Zebrias zebrinus along the coastal waters of China

The so-called zebra sole includes a group of small flatfishes characterized by transverse band pairs on the ocular side and distributed throughout shallow waters along the coast of the Indo-West Pacific Ocean. Sev-eral species of the zebra sole have been recorded from the coastal waters of China. Morphological analysis of 1 107 specimens of the zebra sole from 15 successive localities along the China’s coast demonstrated that no significant variations among these localities were found on the basis of meristic counts and morphometric characters. Phylogenetic analysis based onCOI gene sequences of 14 individuals and D-loop of 22 indi-viduals from eight localities showed that they were indistinguishable among these localities. Therefore, both morphological and molecular evidence supported the occurrence of a single species of the zebra sole along the China’s coast. The available name for this species isZebriaszebrinus （Temminck and Schlegel, 1846） in-stead ofZ.zebra （Bloch, 1787）.Zebrias fasciatus（Basilewsky, 1855） andSolea ommatura （Richardson, 1846） are considered here as two synonyms ofZ. zebrinus.

Types of Fish in Need of Protection in Fishing Reservoirs of Bukhara Region

Fishery reservoirs in Bukhara region are located in the lower reaches of the Zarafshan River and are one of the most important reservoirs in western Uzbekistan. Based on the research conducted in the natural and artificial fishery reservoirs of Bukhara region and the analysis of the literature on ichthyofauna of the region, it has been identified that 31 species of fish belonging to 6 genera and 12 families are found in the region. Of these 31 species, 23 species are listed in the Red Data Book of the International Union for Conservation of Nature (IUCN) and 5 species in the Red Data Book of the Republic of Uzbekistan.

Downstream Ichthyofauna of the Zarafshan River

The lower reaches of the Zarafshan River are one of the most important watersheds in western Uzbekistan. Based on the research conducted in the lower reaches of the Zarafshan River and the lower Zarafshan watersheds, as well as the analysis of the literature on ichthyofauna of the region, it was determined that currently there are 6 species and 31 species of fish belonging to 12 families.

Genetic diversity and the biogeographical process of Acheilognathus macropterus revealed by sequence variations of mitochondrial cytochrome b gene

In this study,thirty-six individuals of Acheilognathus macropterus were collected from the Heilongjiang River,the Yangtze River,and the Nandujiang River.Partial mitochondrial cytochrome b gene region(636 base pair)was sequenced to these samples and 22 haplo-types were found.With A.chankaensis and A.tokinensis as outgroups,their relationships were analyzed.The p-distances were calculated with Mega software and a molecular phylogenetic tree was constructed using the neighbor-joining(NJ)method.The proportions of main morphological characters were compared as well.P-distances showed that the genetic differences in A.macropterus samples were far smaller than those between these samples and the outgroups.The molecular phylogenetic tree shows that samples with barbels and those without barbels were intermingled.There was no distinctive difference in proportions of morphological characteristics among them.These results suggested that samples with barbels and those without barbels(formally identified as A.taenianalis)are the same species;A.taenianalis is synonymous with A.macropterus.The thirty-six individuals were grouped into five clades and the positions of the samples in the clades were correspondingly grouped within their geographical distributions.Among the five clades,clades 1 and 5 included samples from the Heilongjiang River and Nandujiang River respectively.The samples from the Yangtze River scattered into clades 2,3,and 4.There were distinctive genetic differences(>5%)among them.Interestingly,the distributions of the 21 samples in these three clades were not correlated to their geographical distributions.It is postulated that these genetic differences were due to the bitterlings’mating choice mechanism,the prozygotic isolation.The genetic differences between the fish from Nandujiang River and those from the mainland indicated that they were separated early.However,the small genetic differences among the samples and the positions of the fish from the Heilonjiang River in the molecular phylogenetic tree indicate that fish in Heilongjiang River might have dispersed from the Yangtze River to that area much later.