The widespread sea hare species Aplysia parvula includes four genetically distinct lineages, containing a total of ten different species. While the four lineages can be differentiated by their external characteristics, species in each clade are often morphologically indistinguishable. A review of literature and type material revealed that several available names exist for species recognized herein: Aplysia parvula is retained for a species from the north-eastern Atlantic; A. atromarginata, A. elongata, A. nigrocincta and A. japonica are resurrected for species from the western Pacific Ocean, the Hawaiian Islands, the Indian and western Pacific Oceans, and Japan and Korea, respectively. Two new species names are introduced for animals from the eastern Pacific, and the Atlantic and Indian Oceans. Mitochondrial sequences from Mediterranean and eastern Atlantic specimens identified as A. parvula, resulted to be A. punctata. However, two specimens were heterozygotes of histone H3 alleles of A. punctata and of a new Atlantic species described herein, suggesting they could be hybrids. These results contradict the hypothesis that the Mediterranean was colonized by A. parvula. If an invasion occurred, it was a limited introgression of nDNA from an Atlantic species into native A. punctata populations.
Valdés, Á . (2012). Molecular systematics of the 'Navanax aenigmaticus' species complex (Mollusca, Cephalaspidea): Coming full circle. -Zoologica Scripta, 41, 374-385. Molecular evidence from the mitochondrial COI and 16S genes and the nuclear H3 gene indicate that the traditionally recognized cephalaspidean sea slug species Navanax aenigmaticus consists of three deeply divergent lineages with disjunct ranges in the eastern Pacific, western Atlantic and eastern Atlantic. Each of these allopatric lineages is highly variable in colour and body size, which hampers identification of some possible consistent differences between them. Some conchological differences between the three lineages seem to be correlated with the groupings resulting from the analyses of molecular data, but the results of the morphological studies are inconclusive. Because of the presence of well-supported divergences and molecular synapomorphies, these lineages are herein considered to be three separate cryptic species. A review of the literature and available type material was conducted to determine the valid name for each of the three species. In other to promote nomenclatural stability, the oldest name with a description that allows a positive identification was selected over older, taxonomically ambiguous names. The conclusion of this revision is that the valid names for the species are Navanax nyanyanus (Edmunds 1968)eastern Atlantic, Navanax gemmatus (Mö rch 1863) -western Atlantic and Navanax aenigmaticus (Bergh 1893) -eastern Pacific.
Understanding of evolution and systematics of Calcarea (Porifera) have not yet met a corresponding increase in the knowledge of diversity and distribution of these sponges in several parts of the world. Peru is an emblematic example of this lack of taxonomic knowledge, as only three shallow-water species of sponges have hitherto been reported from its 3000 km coast. With the aim of studying sponges of Peru, an integrative taxonomy approach (morphology, molecules, and biogeography) was used in order to achieve sound species identifications. The first findings of Peruvian calcareous sponges are presented here. Eight species are described in the subclass Calcinea, of which five are new to science. The retrieved biogeographical patterns are either locally endemic, widespread, or discontinuous over large areas. Clathrina antofagastensis was previously known from Chile, while C. aurea and Ernstia tetractina had been reported from the Atlantic (Brazil), and thus represent the first genetically confirmed tropical amphi-American distributions of species not yet found on both sides of the Isthmus of Panama. Our results reveal a richer Tropical East Pacific sponge fauna than the Warm Temperate South-Eastern Pacific one.
ABSTRACT. Diet and food preferences of the green turtle Chelonia mydas were analyzed based on digestive tract contents of dead specimens caught incidentally by an artisanal gillnet fishery in Sechura Bay, northern Peru. We examined 27 digestive tracts and identified 35 prey items. The sampled turtles were all juveniles (CCL = 53.7 ± 1.2 cm, range 40.5-67.0 cm). The prey items were grouped into six categories: algae, cnidarians, mollusks, arthropods, chordates and garbage/anthropogenic debris. The items with the highest Frequency of Occurrence values (% FO) were: Caulerpa filiformis (77.8%), Loligo gahi (eggs) (51.9%) and Rhodymenia corallina (44.4%). By weight (% W), the most important items, were L. gahi (eggs) (33.3%), Stomolophus sp. (7.3%) and Aphos porosus (6.5%). According to the Preponderance Index (%IP), the preponderant item was L. gahi (eggs) with 6.1% and 61.2% during winter-spring and summer-autumn, respectively. According to the Resultant Weight index (Rw) of wet items, the most important items were: C. filiformis (13.1%), L. gahi (eggs) (10.5%), R. corallina (7.4%), plastic (7.5%), Gigartina chamissoi (5.1%). Garbage/anthropogenic debris was common in the digestive tracts analyzed. Plastic items had a frequency of occurrence of 44.4%. A greater diversity of food items was observed during summer and autumn. This study shows that juvenile C. mydas forage on a variety of resources. We recommend that conservation plans, land use planning and future management plans in the Sechura Bay include green turtles as a sentinel species for monitoring biodiversity of marine resources and the degree of pollution in the Bay.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.