Anthropogenic Marine Debris (AMD) in the SE Pacific has primarily local origins from land-based sources, including cities (coastal and inland), beach-goers, aquaculture, and fisheries. The low frequency of AMD colonized by oceanic biota (bryozoans, lepadid barnacles) suggests that most litter items from coastal waters of the Humboldt Current System (HCS) are pulled offshore into the South Pacific Subtropical Gyre (SPSG). The highest densities of floating micro- and macroplastics are reported from the SPSG. An extensive survey of photographic records, unpublished data, conference proceedings, and published studies revealed interactions with plastics for 97 species in the SE Pacific, including 20 species of fish, 5 sea turtles, 53 seabirds, and 19 marine mammals. Sea turtles are most affected by interactions with plastics, underlined by the fact that 4 of the 5 species suffer both from entanglement and ingestion. Reports gathered in this review suggest that interactions along the continental coast are mostly via entanglement. High frequencies of microplastic ingestion have been reported from planktivorous fish and seabirds inhabiting the oceanic waters and islands exposed to high densities of microplastics concentrated by oceanic currents in the SPSG. Our review also suggests that some species from the highly productive HCS face the risk of negative interactions with AMD, because food and plastic litter are concentrated in coastal front systems. In order to improve the conservation of marine vertebrates, especially of sea turtles, urgent measures of plastic reduction are needed.

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Impacts of marine plastic pollution from continental coasts to subtropical gyres-fish, seabirds, and other vertebrates in the SE Pacific

A review of the primary literature on the cartilaginous fishes (sharks, skates, rays and chimaeras), together with new information suggests that 106 species occur in Chilean waters, comprising 58 sharks, 30 skates, 13 rays and five chimaeras. The presence of 93 species was confirmed, although 30 species were encountered rarely, through validated catch records and sightings made in artisanal and commercial fisheries and on specific research cruises. Overall, only 63 species appear to have a range distribution that normally includes Chilean waters. Actual reliable records of occurrence are lacking for 13 species. Chile has a cartilaginous fish fauna that is relatively impoverished compared with the global species inventory, but conservative compared with countries in South America with warm-temperate waters. The region of highest species richness occurs in the mid-Chilean latitudes of c. 30–40° S. This region represents a transition zone with a mix of species related to both the warm-temperate Peruvian province to the north and cold-temperate Magellan province to the south. This study provides clarification of species occurrence and the functional biodiversity of Chile's cartilaginous fish fauna.

Not all fish are equal: functional biodiversity of cartilaginous fishes (Elasmobranchii and Holocephali) in Chile

Eggcases of eight rajiform skates (Dipturus nidarosiensis, D. oxyrinchus, Leucoraja melitensis, Raja asterias, R. brachyura, R. clavata, R. miraletus and R. polystigma) present in the central-western Mediterranean are described, based on specimens obtained from fishery surveys. Eggcase features such as dimensions, horns and apron lengths, and presence/absence of lateral keels were crucial to discriminate the eggcases of the various species. Morphological and morphometric data, confirmed by the multivariate analysis, indicated that the eggcase of R. miraletus and L. melitensis were distinct from those of the other species for being unkeeled. Within the species having keeled eggcases, those of the genus Dipturus and R. brachyura were discriminated from the remaining group by having the largest dimensions and aprons. Sandy bottoms (<100–150 m depth) were identified as egg-laying sites (i.e. sites with females bearing eggcases in uteri) for many species belonging to genus Raja Raja asterias, R. brachyura, R. miraletus and R. polystigma). The finding of R. asterias and R. miraletus carrying eggcases yearly on the same sites, seems to confirm the theory that many rajid species demonstrate site fidelity, returning to the same depositional area on an annual basis. Some remarks on reproductive biology of these skates are also provided. The eggcase identification key reported here represents the first for the Mediterranean and may be useful, in the future, to identify egg-laying grounds of skates with a nonlethal method.

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Morphological descriptions of the eggcases of skates (Rajidae) from the central-western Mediterranean, with notes on their distribution

Almost a century of oblivion: Integrative taxonomy allows the resurrection of the longnose skate Zearaja brevicaudata (Marini, 1933) (Rajiformes; Rajidae)

Recent molecular evidence has called into question the identity of skates collected in the waters off the Falkland Islands previously identified as Zearaja chilensis. NADH2 sequence data indicate that these specimens are not conspecific with those currently referred to as Z. chilensis from Chile and, in fact, represent a novel cryptic species. This study aimed to investigate this hypothesis based on morphological comparisons of specimens from the coasts of both western and eastern South America. In total, 50 specimens from Chile and 41 specimens from the Falkland Islands were collected and examined; morphometric data were generated for a subset of specimens from both areas. NADH2 sequence data were generated for a total of 19 specimens from both areas, as well as specimens of Z. nasuta from New Zealand, D. pullopunctatus from South Africa, D. oxyrinchus from the Azores, Okamejei hollandi, and O. cairae from Borneo, and O. kenojei from Japan. Based on morphological and molecular analyses, Zearaja is synonymized with Dipturus and species assigned to the former genus are transferred to the latter genus. A neotype is designated for D. chilensis and this species is redescribed. Dipturus lamillai sp. nov. is described based on specimens from the Falkland Islands. Comparison of our NADH2 data with data for mitochondrial genomes generated from tissue samples taken from two specimens originally identified as Z. chilensis, indicate that, while the sample from Chile came from a specimen of D. chilensis, that from the skate steak obtained from a restaurant in Korea actually came from a specimen of D. lamillai sp. nov. This emphasizes the importance of confirming both the provenance and identity of specimens from which sequence data are generated and submitted to GenBank if misidentifications are to be avoided.

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Redescription and taxonomic status of Dipturus chilensis (Guichenot, 1848), and description of Dipturus lamillai sp. nov. (Rajiformes: Rajidae), a new species of long-snout skate from the Falkland Islands

Egg capsules of Zearaja chilensis were obtained from individuals kept in captivity and from dead specimens captured in Valparaiso Bay, central Chile. One female under laboratory conditions deposited three pairs of egg capsules in 6 days. The egg capsules of Dipturus trachyderma were obtained from a female captured in Valdivia, south Chile. Fresh egg capsules of both species were golden-brown and thick walled. Size of egg capsules of Z. chilensis ranged from 94 to 144 mm in capsule length and 64 to 76 mm in capsule width. Those of D. trachyderma ranged between 197 and 199 mm in capsule length and 110.0 and 129.0 mm in capsule width. Range and mean values of capsule length and width of egg capsules described in this study were smaller than those reported for the same species in the south-western Atlantic Ocean. This is the first report on egg-laying rate of Z. chilensis and the first description of egg capsules of Z. chilensis and D. trachyderma from the south-eastern Pacific Ocean.

Egg capsules of the yellownose skate Zearaja chilensis (Guichenot 1848) and the roughskin skate Dipturus trachyderma (Krefft and Stehmann 1974) (Rajiformes: Rajidae) from the south-eastern Pacific Ocean

A total of 42 egg capsules of Sympterygia lima are examined in this study. Freshly laid egg capsules are pale yellow-brownish in color and turn to dark brown over time in sea water. Dorsal and ventral surfaces are soft and slightly striated. Anterior horns are shorter than posterior and are arranged in parallel. Posterior horns transition into long coiled tendrils, which are the first to emerge through the cloaca during egg-laying. Notes on oviposition rates are discussed; these were shown to vary from 4 to 20 days, with two eggs being deposited each time. The presence of tendril-like posterior horns is not common in rajids. They seem to occur only within the genus Sympterygia, becoming a useful character for distinguishing them from other egg capsules that may be found in the same latitudinal range. Egg capsule characteristics may be useful to help identify the species responsible for egg-laying sites and, indirectly, the reproductive cycle with a nonlethal method.

Egg capsules of the Filetail fanskate Sympterygia lima (Poeppig 1835) (Rajiformes, Arhynchobatidae) from the southeastern Pacific Ocean, with observations on captive egg-laying

Twelve egg capsules laid in captivity by three females of Dipturus chilensis were incubated in the laboratory. After 252 ± 9.4 days, 10 skates successfully hatched, with a mean total length, disc length, and disc width of 17.2, 7.4, and 11.4 cm, respectively. This is the first report of captive hatching of D. chilensis and its corresponding incubation period.

First observations on captive hatching and incubation period of the yellow-nose skate Dipturus chilensis (Rajiformes: Rajidae), from the South-Eastern Pacific Ocean.

Naití Morales

Papers

Egg capsules of the yellownose skate Zearaja chilensis (Guichenot 1848) and the roughskin skate Dipturus trachyderma (Krefft and Stehmann 1974) (Rajiformes: Rajidae) from the south-eastern Pacific Ocean

Egg capsules of the Filetail fanskate Sympterygia lima (Poeppig 1835) (Rajiformes, Arhynchobatidae) from the southeastern Pacific Ocean, with observations on captive egg-laying

First observations on captive hatching and incubation period of the yellow-nose skate Dipturus chilensis (Rajiformes: Rajidae), from the South-Eastern Pacific Ocean.