Understanding of the spatial distribution and habitat use in different stages of a life cycle represents the essential aspect of threatened species management and conservation. In the present paper, the spatial and temporal patterns of habitat use in juvenile and adult life stages of the long-snouted seahorse Hippocampus guttulatus in the Mar Piccolo of Taranto (Apulia—Italy) (40°28′N, 17°16′W) were examined. From October 2012 to January 2014, monthly visual censuses were conducted in six coastal habitats of a focal area (Buffoluto site). Of a total of 317 individuals of the long-snouted seahorse that were sighted, 148 were juveniles, 82 adult females and 87 adult males. Our results showed significant differences in the habitat use between adult and juvenile life stages of H. guttulatus. Adult individuals were mainly concentrated within Cladophora prolifera beds and the wood poles of a mussel farm at 2–4 m of depth, while juvenile individuals were mainly present in shallower water (0.4–1 m) on artificial hard substrates covered by a brown algae turf. Assessing and describing the habitat use within different life stages of H. guttulatus represent a useful tool to support species conservation by protecting the habitats it uses

The aim of this study was to provide further knowledge of the ecological, spatial, and temporal distribution and life‐cycle traits of the sympatric seahorse species Hippocampus hippocampus and Hippocampus guttulatus. From 2011 to 2014, data were collected from 20 sites along the Apulian coast (Southern Italy) in order to cover a wide range of coastal marine, open water, and lagoon sites, from the surface to a depth of 48 metres. Seahorses were found at seven of the 20 sites investigated. Both species displayed temporal persistence, patchy distribution, and a high spatial demographic heterogeneity. This study revealed a smaller maximum size and size at maturity of H. guttulatus than has been reported elsewhere. Although it is possible that environmental factors are influencing the size of these animals, there may be genetic explanations, especially for lagoon populations. Despite the fragmented distribution and often low abundance found along the Apulian coast, some seahorse populations appear to be locally persistent and stable over time, suggesting that there is a need for appropriate location‐specific conservation strategies. Not just maintaining but increasing the area of artificial substrates, which enhance habitat complexity and provide holdfasts, could represent a possible approach to help conserve marine littoral biodiversity and to protect endangered species in lagoons.

The north-east Atlantic (NEA) is an important and complex biogeographic region with a very rich marine fauna. However, little is known about the role of the Macaronesian islands in the evolutionary history and diversification of marine invertebrates in the NEA. Among the amphipods, the members of the family Hyalidae are particularly common and abundant in intertidal rocky shores of NEA. In this study, we aimed to investigate the genetic structure and diversity of seven hyalid species inhabiting the Macaronesian, European and Moroccan Atlantic coasts, with a focus on the genetic differentiation between island and Continental populations. Analysis of mitochondrial DNA sequences of the cytochrome oxidase I gene, unravelled a very high level of hidden diversity, consisting of 26-32 molecular operational taxonomic units (MOTUs), the majority of them recorded in Macaronesian populations. Except for Apohyale stebbingi, all remaining MOTUs were in general allopatrically distributed, with a trend for segregation between islands and Continental populations on one side, but also for the occurrence of private MOTUs among islands. Results indicate distinct evolutionary and diversification patterns among Hyalidae species, but a strong separation between Continental and islands' lineages appears to be a common feature to all of them. Apparently, the complex geomorphological history of the Macaronesian archipelagos served as an important promoter of extensive 360 | DESIDERATO ET Al.