In this paper, we record the occurrence for the first time of two sea cucumber species from the Persian Gulf (Hormuz Island). Sea cucumber samples were collected in the sub-tidal zone of the island during low tide. Species identification was accomplished using morphological keys and a review of their ossicles. The collected specimens provide evidence that Holothuria bacilli and Holothuria insignis are present in the Persian Gulf waters.

We report the first record in the Mediterranean Sea of the minute Indo-Pacific venerid bivalve Costellipitar chordatum. The species has recently established a small population off the central coast of Israel. Numerous live specimens of Gouldiopa consternans, at several locations off the Israeli coast, confirm the presence of a fast growing population. This is the first record of the species from Israel, following a recent report from Turkey.

Two specimens of the penaeid shrimp Penaeus aztecus, a West Atlantic species, were collected off Castiglione della Pescaia, Tyrrhenian coast of Italy. The species identity was confirmed based on morphological characters and by sequencing 510 nucleotides of the mtDNA 16sRNA gene. This alien species has been previously recorded off Turkey, Greece and Montenegro.

The Red Sea record of the Ambon scorpionfish Pteroidichthys amboinensis is confirmed based on two specimens collected at Eilat, Israel in 1966 and in 1997. The species is widespread but very rare, known from scattered localities in the Indo-West Pacific, otherwise occurring from India and Indonesia east to Marquesas Islands.

Specimens of Bursatella leachii Blainville, 1817 were collected from Pulicat Lake along the east coast of India at depths of up to 1 m and the maximum number of this species were recorded at a depth of 20 cm (13°33′57″N 80°10′29″E) on a sandy soil bed. A thorough literature survey on the species revealed this study to be the first report of its occurrence from this region. The present investigation describes a review on the occurrence and morphological features of this specimen.

Nephroselmis pyriformis (N. Carter) Ettl is reported for the first time from the north-eastern Mediterranean Sea coast. The species was isolated from the samples collected on 21 September 2013. The morphology of live cells is described based on light microscopy. Photographic and video images of the species are also presented.

Morphological and molecular data on brittle stars from the Saint Peter and Saint Paul Archipelago, a very small isolated group of islets situated between South America and Africa, are hereby presented. We found no endemic ophiuroids. Instead, the five species, Amphipholis squamata, Ophiactis lymani, Ophiactis savignyi, Ophiocomella ophiactoides and Ophiothrix (Ophiothrix) angulata, are either cosmopolitan or derived from the equatorial western Atlantic region. Results indicated a western Atlantic colonization and highlighted the existence of cryptic species in the genus Ophiactis.

An adult male specimen of Uca rapax (Crustacea, Decapoda, Ocypodidae), containing bilaterally hypertrophied chelipeds, was found in the mangrove area of the Rio Grande do Norte state, north-eastern Brazil. The chelipeds are subequal in size and similar to the major cheliped of normal male specimens of Uca rapax. This paper is the first record of the aforementioned anomaly for the species from the Brazilian coastline.

The alien nudibranch Polycera hedgpethi Er. Marcus, 1964, has been found in the Gulf of Cádiz (El Portil, Huelva). The present record in the Gulf of Cadiz could be considered an opportunity to connect the isolated Eastern Atlantic records for this species with those from the Mediterranean, even taking into consideration the possible unreported presence of this species along the North African Mediterranean coast. The collected specimens exhibited reproductive behaviour, suggesting the possibility of future additional records for this locality.

This paper presents a review of the vagrant species recorded in different areas of the South Shetland Islands, Antarctica. Seven bird species were observed at Elephant Island, King George Island and Nelson Island. Elephant Island was the area with the largest number of species recorded (N = 5). Among all the species observed in Antarctica, White-rumped Sandpiper and Cattle Egrets were the species with the most observations. There are different hypotheses used to explain the presence of vagrant bird species in Antarctica: (I) storms, irregular ocean currents, climate change and navigator errors can suggest why the birds are registered out of their usual areas of distribution; (II) changes in ocean currents may influence resource distributions and, consequently, influence bird distribution patterns. It is important to gather more information on bird species that are using new areas, to understand the diversity of birds in Antarctic regions, to characterize changes in migratory routes and to observe the responses of species facing global climate change.

Sterrer's cave shrimp (Parhippolyte sterreri) is recorded for the first time from San Salvador Island, Bahamas. A single adult specimen was collected in June 2011 with hand nets at the southern conduit mouth in Mermaid Pond, an anchialine pond on the south-east corner of the island. Twelve additional specimens were collected in June 2013 from two additional sites near Mermaid Pond (Dunk City Pond and the Pigeon Creek Conduit). These collections represent a minor range extension of P. sterreri in the Bahamas. Additionally, we report on populations of Barbouria cubensis observed in 17 other anchialine ponds on San Salvador Island.

Between 2007 and 2014, three individual thorny seahorses, Hippocampus histrix, were recorded in Port Stephens, New South Wales, Australia. Specimens ranged in size from 6 to 8 cm and were considered to be females. This extends the known range of H. histrix along the east coast of Australia by 1700 km.

Albinism is a hereditary lack of pigmentation caused by deficiencies in enzymes related to the metabolism of melanin. This mutation is present in marine vertebrates and invertebrates, including the Holothuroidea class; nevertheless, information about the occurrence of albinism in these kinds of echinoderms is scarce and refers to species from temperate and cold regions of the ocean. In 2013, we observed two albino individuals of Isostichopus fuscus, one at Loreto (25°45′54″N, 111°14′36″W) and the second one at Los Angeles Bay (29°02′54″N, 113°29′49″W). This is the first documented record of albinism for this species.

This record represents the northernmost occurrence of Lessepsian migrant fish Siganus luridus in the Aegean Sea. A single specimen was caught off the coast of Assos, Edremit Bay, in November 2014 by trammel net at a depth of about 2–3 m on a sandy, rocky bottom mixed with Posidonia. Here, the morphometric and meristic characteristics of the specimen are identified and the dispersion of the species in the Mediterranean Sea is briefly discussed.

The species Homostichanthus duerdeni and Anemonia sargassensis are recorded for the first time in the Mexican Caribbean. Homostichanthus duerdeni is taxonomically diagnosed, and images from living specimens, including external and internal features and cnidae, are provided. The extension of the geographical distribution range of A. sargassensis is discussed, as well as the taxonomic status of the previous records of actiniarians in the Mexican Caribbean. An updated list of sea anemones in the region is provided, comprising 15 species in 11 localities along the Mexican Caribbean.

We report here, for the first time, the existence of a white colour morph Elacatinus figaro, an endemic threatened cleaner goby from the Brazilian Coast. The specimen from this study lived in a cleaning station along with other E. figaro. Records were made based on pictures and the specimen was collected and preserved for genetic studies. Although the strong bright yellow colour is of vital importance for attracting other fish to the cleaning station, we speculate that living alongside regular-coloured individuals can diminish the disadvantage of not having the flashy stripe.

The occurrence of the rare serpent eel Ophisurus serpens is reported here for the first time from the Anatolian coasts of the South Aegean Sea. On 5 January 2015, a single specimen with a total length of 121. 2 cm and 363.14 g was collected by seine boat off Gökova Bay, Turkey. This finding shows that its population is expanding southwards, from Izmir to the Anatolian coasts of the Aegean Sea.

Echinolittorina punctata was historically distributed in the southern sectors of the Mediterranean Sea. However, in the last decades a progressive range extension has occurred. In this context, new populations in France (Colliure, Cap d'Agde) and in Italy (Monte Argentario, Tuscany) are reported here. The population in Cap d'Agde is the northernmost in the entire Mediterranean Sea, the population in Monte Argentario is the northernmost along the Italian Tyrrhenian coastline and along the direction of range extension described in the last few years. Details on population density and size frequency distributions in Monte Argentario are provided, showing a decrease in density and an increase in minimum size from south to north. New records are also provided from Salamina Island and Rhodes Island in Greece. The latter likely dates back to 1836–1837 and is the first record from the Mediterranean Sea. This record confirms that the species was widely distributed in the Levantine Sea at the time, although records from Greece and Turkey are extremely rare in the literature and in museum collections.

The amphinomid polychaete Linopherus cf. canariensis was recorded for the first time in the coast of Rio de Janeiro (South-east Brazil). In 2011, a total of 15 specimens were collected in the intertidal zone of Itaipu Beach (Niterói) in dead Encope emarginata test fragments. In this study, the specimens are described, and a brief discussion about their morphological variation and invading potential is provided.

Three species of bivalves, Thyasira succisa, Lyonsia norwegica and Poromya granulate, were recorded for the first time in the Adriatic Sea during surveys conducted from 2010 to 2012 on offshore relict sand bottoms at a depth range of 45–80 m.