Massimo Avian

• associated professor
• University of Trieste

Sponges are now requested for their commercial, industrial and pharmaceutical importance. This led to an increase in demand in the global markets with uncontrolled and excessive harvesting pressure that, together with diseases outbreaks, put wild populations at risk, with several habitats completely looted. Aquaculture of sponge fragments poses an...

Very little information is reported for parasites of cnidarians, therefore, the present work aimed to investigate parasitic infections in one of the most widespread jellyfish in the Mediterranean Sea, Rhizostoma pulmo. The goals were to determine prevalence and intensity of parasites in R. pulmo, identify the species involved through morphological...

Due to the increasing mass mortality of Pinna nobilis, mainly caused by the protozoan Haplosporidium pinnae along the Mediterranean Sea, it is necessary to develop rapid and effective methods to detect the pathogen. The present study describes the development and validation of a species-specific assay based on hydrolysis probe chemistry to detect H...

The investigation of jellyfish gastrovascular systems mainly focused on stain injections and dissections, negatively affected by thickness and opacity of the mesoglea. Therefore, descriptions are incomplete and data about tridimensional structures are scarce. In this work, morphological and functional anatomy of the gastrovascular system of Rhizost...

The major component of the animal egg yolk is the lipoglycoprotein vitellin, derived from its precursor vitellogenin (VTG), which is produced species-specifically in decapod crustaceans in the hepatopancreas and/or in the ovary of reproductive females. Previous studies on Procambarus clarkii vitellogenesis report the existence of two single VTGs. H...

This manuscript presents four new observations of the jellyfish Mawia benovici in the Adriatic Sea. This new species was recently identified as Pelagia benovici by Piraino et al. (2014) and then placed in the new genus Mawia by Avian et al. 2016. This species is rare and is almost exclusively observed in the Adriatic Sea. Interestingly, the majorit...

Sanderia malayensis is a scyphozoan species present in the Indian and Pacific Oceans, ranging from the Suez Canal to Japan. Although this jellyfish is commonly kept in aquariums around the world, there is a knowledge gap regarding its biology and ecology, especially at the polyp stage. In this study, we tested the asexual reproductive activity of S...

Cotylorhiza tuberculata is an important scyphozoan jellyfish producing population blooms in the Mediterranean probably due to pelagic ecosystem's decay. Its gastric cavity can serve as a simple model of microbial – animal digestive associations, yet poorly characterized. Using state-of-the-art metagenomic population binning and catalyzed reporter d...

This study provides new and additional data on morphology and a phylogenetic analysis of the recently described species Pelagia benovici Piraino, Aglieri, Scorrano & Boero, 2014 from the Northern Adriatic (Mediterranean Sea). Comprehensive morphological analyses of diagnostic characters, of which the most significant are marginal tentacles anatomy,...

Identification of organisms is traditionally based on the use of "classic" identification keys, normally printed on paper. These keys have several drawbacks: they are mainly based on the systematics, requiring identification of orders, families and genera at first; they are written by experts for other experts, in a specific scientific jargon; they...

Aim. Rhizostoma pulmo is a jellyfish very common along the Mediterranean Sea coasts, that can cause mild dermatitis to bathers. It has a simple structure with a dome-shaped umbrella and 8 oral arms. The tentacles contain the nematocysts in which the toxins are present. Till now the toxins of this jellyfish have not been completely identified but th...

The spermatozoon of Carybdea marsupialis (Cnidaria, Cubozoa, Carybdeidae) is a primitive sperm with a short pear-shaped head and a long tail. The head contains a pyriform nucleus, six mitochondria, two centrioles aligned on the major axis of the sperm, and an anchoring apparatus formed by a complex pericentriolar system and a pyramid-like appendix...

Background. Numerous studies report procedures to isolate jellyfish venom, a complex mixture of polypeptides and enzymes. In the present study the dermotoxicity of two different purified preparations of nematocysts of Olindias Sambaquiensis, a hydromedusa endemic at the Blanca Bay (Argentina), has been evaluated by means of prick, patch and scratch...

This study investigates the biology of Esox lucius in an irrigation ditch, Storta Roggia (Torviscosa, Udine), in the lower plain of Friuli‐Venezia Giulia (north‐eastern Italy). About twenty fish were captured monthly from May 1996 to May 1997. Variables such as age (as determined from reading scales) and stomach contents were recorded from these fi...

A tropical jellyfish, Rhopilema nomadica (Scyphozoa, Rhizostomeae) has recently invaded the eastern Mediterranean. Its painful stings have been the bane of bathers and fishermen from Egypt to Turkey. This paper reports on the presence of haemolytic activity and alpha-chymotrypsin-like serine protease activity in the venom of the R. nomadica nematoc...

Rhopilema nomadica—a recently discovered scyphomedusa in the eastern Mediterranean—is considered a lessepsian migrant. Its nematocysts were extracted from the scapular and mouth-arm tentacles and examined using light and electron microscopy techniques. The morphometric parameters of the nematocysts were measured before and after complete discharge....

A haemolytic toxin was purified by ion-exchange chromatography and FPLC gel filtration from the nematocysts of the jellyfish Carybdea marsupialis. Sheep red cells, but not human or rabbit red cells, were susceptible to lysis by the toxin. The toxin is a protein with an apparent molecular mass of about 102-107 kDa, is heat labile, highly unstable in...

Olindias sambaquiensis, Muller 1861 (Hydrozoa: Limnomedusae: Olindiidae) is a neritic jellyfish endemic in the Blanca Bay area (South of Buenos Aires, Argentina). In this paper we describe the first report of a dermatitis caused by this jellyfish in a thirty-four-year-old marine biologist who presented with an erythematous vesicular eruption after...

Carybdea marsupialis (Cnidaria, Cubozoa), a jellyfish found in the Adriatic Sea only in recent years, was previously considered innocuous and only recently has been described by us as dermotoxic to man. In the present study we evaluated the activity of a purified preparation of nematocysts of Carybdea marsupialis in men. A crude nematocystic fracti...

The sequence of vitellogenesis as related to size increase of the oocytes of Pelagia noctiluca (Forskl) (Scyphozoa, Semaeostomeae) was examined to assess the influence of climatic factors on its reproductive period in the central and northern Adriatic Sea. From 1981 to 1985, 5 specimens with similar diameter were sampled each month. One ovary was e...

Oocyte development was followed in 4 species of Scyphomedusae. In Pelagia noctiluca a centrifugal maturity gradient is present. Vitellogenesis may be related first to exogenous endodermal production and later to oocyte endogenous activity. Simultaneously, the paraovular body (POB) develops from the secondary endoderm; it is connected to the oocyte...

Nematocysts of the scyphozoans Pelagia noctiluca and Rhizostoma pulmo were examined. In R. pulmo 4 types of nematocyst were observed: heterotrichous microbasic euryteles; holotrichous isorhizas; atrichous a-isorhizas; and atrichous -isorhizas. In P. noctiluca 5 types of nematocyst were seen: heterotrichous microbasic euryteles; heterotrichous isorh...

The correlation between seawater temperature, pulsation rate of the umbrella, and motility of adult specimens of Pelagia noctiluca was studied by means of laboratory experiments and observations of natural coastal aggregations in the Gulf of Trieste (northern Adriatic Sea). It was found that: (i) the pulsation rate of this jellyfish is correlated w...

The behaviour of the oral arms of Pelagia noctiluca (Forsskl) has been investigated in open sea predation and in predation induced both in the laboratory and the natural environment. Specimens were first studied in the field and then collected from coastal aggregations in the Gulf of Trieste, North Adriatic Sea, in December 1985 (Lat. 1340 E, Long....

In vitro experiments on developmental stages and fertilization in Pelagia noctiluca (Forskål) confirm previous observations both in the laboratory (Rottini Sandrini & Avian, 1983) and in the field (Rot‐tini Sandrini et al., 1983/84) that sea temperature exerts a marked effect on this species. Development slows down at 13.5°C compared with 19°C. No...

The development of Pelagia noctiluca (F \mathop oo\mathop o\limits^o rskal) larvae, obtained from fertilization in aquarium, has been observed and recorded from the stage of planula to the stage of ephyra of 1.4 mm in diameter. Nine developmental stages are described, corresponding to the variation in the general morphology, in the morphology of t...