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The distribution of 130 nominal species of the genus Halecium, based on published records, has been mapped for the first time in a comprehensive set of marine ecoregions, to analyse their distribution. Most Halecium species are found at mid- and high latitudes, with some overlaps in distribution ranges across regions. The species richness of Halecium is strongly related to the latitudinal gradient, with maximal diversity at polar and temperate latitudes. Previous detailed studies in the Mediterranean Sea show that large Halecium species of coldwater affinity have regressed or disappeared in recent years, probably due to global warming. Worldwide, however, the overall species richness of Halecium has not changed along the latitudinal gradient over recent decades, with some changes in species composition at temperate-tropical latitudes in both hemispheres, even though the majority of the species that have not been recorded for more than 50 years are of coldwater affinity. The genus can be considered an indicator for biological responses to climate changes for the Mediterranean Sea, but the available distribution data do not allow extending this possibility to the rest of the world. A focused evaluation on the distribution of Halecium species with the addition of new field data might reinforce the picture stemming from the present analysis.

In science museums, teaching panels are an important means of cultural mediation and communication. This study focused on the use and features of panels in museums and we tested panels’ efficacy in conveying information. We assessed the understandability of their messages by verifying the acquisition of information over the short term (quantitative aspect) and identifying difficulties in reading (qualitative aspects). Two panels in the Museo di Biologia Marina “Pietro Parenzan” in Porto Cesareo (Province of Lecce, Italy) were evaluated. The panels had the same content but were different from linguistic and graphic points of view. The study was carried out by interviewing 1,898 middle and secondary-school students of the Province of Lecce (their ages ranging between 11 and 19 years).

Thirty-eight nonindigenous marine species (NIS) (macroalgae, sponges, hydrozoans, molluscs, polychaetes, crustaceans, ascidiaceans and fish), are reported from the Apulian coast of Italy. Shipping, aquaculture and migration through the Suez Canal are the main pathways of introduction of the NIS. In Apulian waters, 21% of NIS are occasional, 18% are invasive and 61% are well-established. It is highly probable that more NIS will arrive from warm-water regions, because Mediterranean waters are warming. Furthermore, some of the successful NIS must have the ability to become dormant in order to survive adverse conditions, either seasonal or during long journeys in ballast waters. The identification of NIS depends greatly on the available taxonomic expertise; hence the paucity of taxonomists hinders our knowledge of NIS in our seas. We propose the creation and maintenance of a network of observatories across the Mediterranean to monitor the changes that take place along its coasts.

The Basking Shark Hall was recently inaugurated in the Marine Biology Museum “Pietro Parenzan” (University of Salento). This provided opportunities to address subjects such as plankton or filter feeding, which are usually disregarded in Marine Biology displays. A questionnaire was administered to visitors (537 students, 9–18 years old) at 3 different times: before the visit to the Basking Shark Hall, immediately after, and after 3 months. Apart from the general trend of positive results emerging from the questionnaires, and a typical progressive diminishing of the acquired information over time, the results highlighted a lack of previous information, the different learning behaviors of males and females, and a different receptivity according to age. The data obtained will be used in elaborating strategies for future didactic proposals in the Marine Biology Museum.

The genus Gastroblasta was proposed by Keller in 1883 for a campanulariid medusa from the Red Sea, G. timida, with round umbrella, multiple radial canals and multiple manubria. A second species, G. raffaelei, with elliptic umbrella, multiple manubria and radial canals, and a great tendency to fission, was subsequently described from the Mediterranean Sea by Lang in 1886. A third species with multiple manubria was described by Mayer in 1900 from Tortugas: Multioralis ovalis (currently ascribed to Gastroblasta). The complete life cycle of a species of Gastroblasta, whose polyp stage was collected inside sponges from the Ligurian Sea and the Ionian and Adriatic Seas, is described. The first stage of medusa development is a typical Clytia with four radial canals and four tentacles, then the medusa becomes similar to G. ovale, to subsequently acquire the typical morphology of G. raffaelei. The species G. timida and G. raffaelei are considered as valid representatives of the genus, sharing the characters of multiple manubria and radial canals. The medusa of G. ovale has a diagonal canal system, instead of multiple radial canals, sharing with Gastroblasta the presence of multiple manubria only: it is proposed to resurrect the genus Multioralis to accommodate it.

The genera Zanclea, Halocoryne and Zanclella are surveyed, with description of all known species. including eight new ones of Zanclea (Z. bomala, Z. divergens, Z. fanella, Z. giancarloi, Z. medusopolypata, Z. retractilis, Z. gilii, Z. birobitoi), two new species of Halocoryne (H. frasca, H. pirainoid), and two new ones of Zanclella (Z. diabolica, Z. glomboides). For most species, the description covers the whole life cycle. The hydroids of this group can be symbiotic with either bryozoans, bivalves, or corals and only few species are not substrate-specialist. Symbiotic relationships led to polymorphism and colony integration with the hosts. The morphologies of hydroid and medusa stages are often not consistent. so that species with very derived hydroids have non-derived medusae (e.g., Halocoryne pirainoid), or species with very derived medusae have non-derived hydroids (e.g., Zanclella diabolica). The architecture of the newly released medusae of Zanclella is exceptional due to a sharp compression of the exumbrella and of the presence of just two radial canals. A phylogenetic scenario is suggested, in spite of the inconsistencies in the rates of change in the two main stages of the cycle.

In many countries, on 12 February (Darwin’s birthday), the theory of evolution by natural selection is celebrated with the rites of Darwin Day. Scientists give conference presentations on evolution...

Codonorchis octaedrus is recorded for the first time since its discovery by Haeckel in 1879. A hydroid colony collected in a cave of the Apulian Coast (between the Ionian and the Adriatic Seas) produced several medusae which have been reared to maturity. This is the first complete description of the species, which was previously considered as doubtful, as was the genus Codonorchis. The diagnostic features for the genus are: hydroid small, naked, sessile, with a single row of few tentacles, gono‐phores on hydrorhiza, medusa with apical projection with apical process from the manubrium, perradial, interradial and adradial ocellate bulbs, two perradial tentacles, horseshoe‐shaped interradial gonads, small mesenteries. The list of Mediterranean hydroidomedusae is updated with the new (or overlooked) records since the last published list (1993). The increase in species number is great (about 10%), showing that the knowledge of biodiversity of even a well‐studied sea as the Mediterranean is far from be...

Science is often carried out with two apparently different approaches. Some scientists make experiments, whereas others make observations; the first ones manipulate the objects they scrutinize, whe...

Zoology and anthropology are usually considered as distinct disciplines, with different scientific communities, journals, scientific societies. The Italian Zoological Union (UZI) and its journal, t...

Proofs that climate change is a reality are increasingly evident: undeniably, the abiotic factors of today have changed much in respect to just a few decades ago. The bearing of these changes, howe...

Zoology is the basic form of human culture. The Bible (Genesis 1: 18) says: Now Jehovah God was forming from the ground every wild beast of the field and every flying creature of the heavens, and h...

Previously, the Italian Journal of Zoology was divided into sections, covering the manifold approaches of zoology. Sections, however, were often unbalanced, with rather few contributions based eith...

The life cycles of three species of Philadella from central California (Phialella zappai n. sp., P. fragilis and P. sp.) are described. The three species have similar hydroids, with similar ecology. The medusae are very distinctive in both morphology and biology. Phialella sp. is delicate and difficult to rear; P. fragilis has a limited growth; and P. zappai shows precocious gonad maturation and continuous growth, with the possibility of becoming sexually mature more than once in its life. An interpretation of these phenomena suggests that the hydroids are basic, less varied, larval stages, as the medusae are the adults.

The production of free medusoids is considered to be a transition from the production of medusae to the abolition of this stage of the life cycle, within a generalized process of paedomorphosis occurring within hydromedusae, in which the hydroid stage is the larva and the medusa stage the adult. The discovery of a species of Haleciidae producing free medusoids allows the reconstruction of the phylogeny of this family according to the following sequence of genera: Campalecium (producing medusae); Hydrantbea producing free medusoids); Hydrodendron (with sporosacs and nematophores); Scoresbia (with sporosacs and nematothecae); Ophiodissa (with sporosacs and nematothecae, branched); Phylactotbeca (with sporosacs, differentiated nematothecae and hydrothecae, branched). The affinities of the medusa stages between Campalecium and Eucbeilota indicate that the Haleciidae originated by the evolution of hydroids of the family Campanulinidae s.l. The Haleciidae evolved further, giving rise to the Plumulariid...