Mafalda Freitas

When natural history collections reveal secrets on data deficient threatened species: Atlantic seahorses as a case study

Natural history collections from museums and private institutions can play an important role supporting decisions in biodiversity conservation. Seahorse populations have suffered a worldwide decline, while many areas remain data deficient including areas subjected to heavy commercial trading, such as the coasts of West Africa. In this work, seahorse collections from museums and public institutions in Macaronesia (Azores, Madeira and the Canary Islands) were initially reviewed (1) to identify specimens not previously determined, and (2) to correct species determinations from Macaronesia and adjacent West African coasts. The morphological data (3) were tested for phenotypic variation of seahorses within and between Macaronesia and adjacent West African coasts. The presence of Hippocampus hippocampus (short-snouted seahorse) and Hippocampus algiricus (West African seahorse) was confirmed for the area, including new sightings along previous geographical distribution ranges. Morphological analyses partitioned seahorse species and several morphotypes within and between Macaronesia and adjacent West African coasts. This phenotypic plasticity was associated with cranial morphology. Such differences are a useful tool for tracking seahorse populations of varying species and origins. New information presented here, is valuable for improving the management and conservation of seahorses, particularly in areas threatened by illegal trading or other anthropogenic activities.

First record of hydrolagus affinis (Holocephali: Chimaeriformes: Chimaeridae) from Madeira and the seine seamount (North Atlantic Ocean)

The smalleyed rabbitfish, Hydrolagus affinis (de Brito Capello, 1868) (Chimaeridae), is recorded from the archipelago of Madeira for the first time, based on seven specimens caught between 1200 and 2500 m depth. This record extends the previously known range of distribution of this species, and also confirms its vertical dis - tribution down to 2500 m. Additional material collected from the Canary Islands and the Azores was used for comparison.

Records of some rare deep-sea fishes caught in the Lion, Susan, and Unicorn seamounts, off the archipelago of Madeira (east-central Atlantic)

Fish communities off the seamounts inside the Madeira exclusive economic zone are scarcely known, hence the need to improve this knowledge. A bottom trawl fishing survey targeting orange roughy, Hoplostethus atlanticus Collett, 1889, was carried out on the Lion, Susan, and Unicorn seamounts in the autumn of 2001. The aim of this paper is to give an account of the catches of that survey, during which 9 tows were conducted and 21 deep-sea fish species caught, including species rarely caught. The following fish species were collected: Chlamydoselachus anguineus Garman, 1884; Scymnodon ringens Barbosa du Bocage et de Brito Capello, 1864; Dalatias licha (Bonnaterre, 1788); Centrophorus squamosus (Bonnaterre, 1788); Deania profundorum (Smith et Radcliffe, 1912); Deania hystricosa (Garman, 1906); Serrivomer beanii Gill et Ryder, 1883; Rouleina maderensis Maul, 1948; Argyropelecus gigas Norman, 1930; Chauliodus sloani Bloch et Schneider, 1801; Macroparalepis nigra (Maul, 1965); Neoscopelus microchir Matsubara, 1943; Gadomus arcuatus (Goode et Bean, 1886); Mora moro (Risso, 1810); Melanonus zugmayeri Norman, 1930; Chaunax suttkusi Caruso, 1989; Diretmoides pauciradiatus (Woods, 1973); Hoplostethus mediterraneus Cuvier, 1829; Beryx splendens Lowe, 1834; Epigonus telescopus (Risso, 1810); Aphanopus carbo Lowe, 1839. The presence of Diretmoides pauciradiatus was confirmed in the area and Gadomus arcuatus was recorded for the first time from Madeira. Aspects of the life history traits of some of the species caught are presented. This includes a first approach to the estimation of the length–weight relations of 11 deep-water, data-deficient species for which prior information, estimated from data collected, did not exist in FishBase and some new insights about the biology of Hoplostethus mediterraneus.

First records of Chimaera opalescens (Holocephali: Chimaeriformes: Chimaeridae) from Madeira and north-west African coast

This study reports new findings of Chimaera opalescens Luchetti, Iglésias et Sellos, 2011, which represent new records of this fish from Madeira and Morocco. The specimens were caught at the depths between 800 and 1221 m. Additional specimens deposited in the Natural History Museum of Funchal (MMF) were also studied as a comparative material and the results are reported herein. The new records of C. opalescens extend the previously known area of distribution of this fish further south.