The anti-predator role of within-nest emergence synchrony in sea turtle hatchlings

Group formation is a common behaviour among prey species. In egg-laying animals, despite the various factors that promote intra-clutch variation leading to asynchronous hatching and emergence from nests, synchronous hatching and emergence occurs in many taxa. This synchrony may be adaptive by reducing predation risk, but few data are available in any natural system, even for iconic examples of the anti-predator function of group formation. Here, we show for the first time that increased group size (number of hatchlings emerging together from a nest) reduces green turtle (Chelonia mydas) hatchling predation. This effect was only observed earlier in the night when predation pressure was greatest, indicated by the greatest predator abundance and a small proportion of predators preoccupied with consuming captured prey. Further analysis revealed that the effect of time of day was due to the number of hatchlings already killed in an evening; this, along with the apparent lack of other anti-predatory mechanisms for grouping, suggests that synchronous emergence from a nest appears to swamp predators, resulting in an attack abatement effect. Using a system with relatively pristine conditions for turtle hatchlings and their predators provides a more realistic environmental context within which intra-nest synchronous emergence has evolved

Fishes of the Vitória-Trindade Chain: Biodiversity, Biogeography and Evolution

Studies on the ecology and biogeography of seamounts and oceanic islands have advanced substantially in the last 60 years. However, few seamounts have been scientifically characterized, with basic aspects of their biodiversity still unknown and many hypotheses not empirically tested. Consequently, the role of seamounts in the evolution for marine species is still unclear. In the south Atlantic, the Vitória-Trindade Chain (VTC) extends ca. 1,200 km offshore the Brazilian coast. For a long time, most of the biological information available was limited to the emergent islands, where a high richness and endemism is found. The seamount chain, situated between the islands and the mainland, is thought to contribute importantly to the regional biodiversity, and has been suggested as stepping-stones, repositories and museums for coral reef species. The goal of this dissertation is to characterize the biogeographic patterns of reef fishes that inhabit the VTC and test hypotheses to explain those patterns. The results reveal large mesophotic reefs sheltering a very high biodiversity, where new records, depth range extensions and new species were reported. The regional biogeography is very complex; species richness does not decrease with distance from the mainland and it is related instead to seamount and island environmental characteristics and ecological traits of the species. Speciation is not only resulted from the islands isolation, as many endemics are widely distributed along the seamounts, and selection and adaptation are stronger drivers of genomic differentiation than is isolation. In conclusion, oceanic islands would unlikely exhibit the biogeographic patterns we observe today in the absence of seamounts as intermittent stepping-stones, reservoirs of coral reef biodiversity

Pempheris gasparinii, a new species of sweeper fish from Trindade Island, southwestern Atlantic (Teleostei, Pempheridae)

Pempheris gasparinii sp. n. is described from five specimens, 59.1–68.0 mm in standard length. It is only known to occur in the shallow reefs of Trindade Island, 1200 km east of the Brazilian coast, in the southwestern Atlantic. Pempheris gasparinii is the third recognized species of Pempheris in the Atlantic Ocean. This new species is morphologically similar to its close relative, P. poeyi, differing by the number of lateral-line scales (51–54 in P. gasparinii vs. 47–49 in P. poeyi), scales below lateral line (10–11 vs. 9), circumpeduncular scales (11–12 vs. 13), head and caudal peduncle lengths (2.7–3.3 vs 3.5–4.0 in head length). Moreover, Pempheris gasparinii shows a 4% genetic divergence from P. poeyi at the cytochrome oxidase I locus (COI), consistent with a lineage split at the beginning of the Pleistocene. This new species represents the 12th endemic fish species from Trindade Island

Impact of commercial fishing on Trindade Island and Martin Vaz Archipelago, Brazil: characteristics, conservation status of the species involved and prospects for preservation

Visual records, radio interviews and onboard observations of the fishing activities during a 58 days scientific expedition to Trindade Island and the Martin Vaz Archipelago were obtained from February to April 2007. The regular activities of four different fisheries were observed: pelagic longline, bottom line, trolling and handline. These fisheries caused mortality of at least seven species with some level threat, according to the International Union for Conservation of Nature list. The establishment of specific restriction norms for hook-and-line activities around the oceanic islands was seen as an alternative for the conservation of the ichthyofauna of the region. Satellite monitoring to track the fishery vessels could be established through the national program as another legal mean to diminish fishing the impact

Liopropoma incandescens sp. nov. (Epinephelidae, Liopropominae), a new species of basslet from mesophotic coral ecosystems of Pohnpei, Micronesia

A new species of the genus Liopropoma Gill found on the lower mesophotic coral ecosystem of Pohnpei, Micronesia, is herein described. Liopropoma incandescens sp. nov. differs from its congeners in coloration, number of lateral-line scales, number of pectoral fin rays, body depth, and snout length. Liopropoma incandescens sp. nov. is the 31st species in the genus. It was collected from a small rocky crevice in a steep slope at 130 m depth. Water temperature was 20 °C and benthic habitat was dominated by gorgonians, sponges and tunicates

Cirrhilabrus wakanda, a new species of fairy wrasse from mesophotic ecosystems of Zanzibar, Tanzania, Africa (Teleostei, Labridae)

Volume: 863Start Page: 85End Page: 9

Two new species of Plectranthias (Teleostei, Serranidae, Anthiadinae) from mesophotic coral ecosystems in the tropical Central Pacific

Two new species of Plectranthias perchlets are described, collected from mesophotic coral ecosystems in French Polynesia and the Republic of the Marshall Islands, in the tropical Central Pacific. Plectranthias polygonius sp. nov. was collected at a depth of 105 m in Tahiti, French Polynesia, and 120 m in Maloelap Atoll, Republic of the Marshall Islands. It was also observed in Moorea and Rangiroa (French Polynesia), and at Majuro and Erikub Atolls, Republic of the Marshall Islands. Plectranthias hinano sp. nov. was collected at a depth of 90–98 m in Tahiti, French Polynesia, and observed in Moorea. The barcode fragment of the cytochrome oxidase I gene of Plectranthias polygonius sp. nov. does not closely match any published sequence of Plectranthias, with approximately 15% uncorrected divergence from several species. Plectranthias polygonius sp. nov. can be distinguished from all of its congeners by coloration and morphology. The barcode fragment of the COI gene of Plectranthias hinano sp. nov. is closest to Plectranthias bennetti, with 5.4% uncorrected divergence. Plectranthias hinano sp. nov. is also distinguished from all of its congeners by morphology, and a coloration that includes two indistinct black spots along the base of the dorsal-fin, and transparent yellow dorsal and anal fin membranes. With this publication, the genus Plectranthias now comprises 58 valid species, with representatives from tropical to temperate waters of the Atlantic, Pacific, and Indian oceans. These two new discoveries add to the growing body of research highlighting the rich biodiversity of mesophotic ecosystems

Roa rumsfeldi, a new butterflyfish (Teleostei, Chaetodontidae) from mesophotic coral ecosystems of the Philippines

Volume: 709Start Page: 127End Page: 13

Pseudanthias hangapiko, a new anthiadine serranid (Teleostei, Serranidae, Anthiadinae) from Rapa Nui (Easter Island)

Pseudanthias hangapiko sp. nov. (Teleostei, Serranidae, Anthiadinae) is herein described from three specimens collected from a depth of 83 m in a mesophotic coral ecosystem off Hanga Piko, Rapa Nui (Easter Island), Chile. Pseudanthias hangapiko sp. nov. can be distinguished from its congeners in live coloration and by the following combination of characters: dorsal-fin rays X, 17; anal-fin rays III, 8; pectoral-fin rays 16 (left side of one specimen 17); vertebrae 10+16; scales relatively large, two scales above lateral-line to base of fifth dorsal spine, and 16–17 circumpeduncular scales; gill rakers 11+23; and a slender body, with greatest body depth 3.6 (3.4–3.8) in SL. The most similar DNA barcodes (mitochondrial COI gene) are from Pseudanthias ventralis Randall, 1979 and Pseudanthias hawaiiensis Randall, 1979, with 16.8% and 17.0% uncorrected divergence, respectively. This fish is one of four new species that were documented from a pair of technical dives at a single location in Rapa Nui, emphasizing the high number of undescribed species likely still unknown in mesophotic coral ecosystems, especially in geographically remote locations. Pseudanthias hangapiko sp. nov. adds to the Rapa Nui ichthyofauna, which hosts the second-highest level of endemism in both shallow and deep-water fishes