Drosos Koutsoubas - Academia.edu (original) (raw)

Papers by Drosos Koutsoubas

In the Mediterranean Sea, infralittoral and circalittoral rocky bottoms (from 15 to 120 m) are ch... more In the Mediterranean Sea, infralittoral and circalittoral rocky bottoms (from 15 to 120 m) are characterized by a biogenic habitat, named "coralligenous", formed by the concretion of calcareous organisms, mainly algal thalli, and- to a lesser extent- by animal skeletons. This complex habitat is inhabited by a rich fauna that belongs to different taxonomic groups. Sponges, bryozoans, cnidarians and ascidians are the most common sessile organisms that inhabit the area while crustacean and molluscs are the common mobile organisms. Little information on the diversity of the molluscs that thrive in the coralligenous habitat is known while this information is highly important for biodiversity management purposes. After thoroughly studying the available and accessible published literature, a database for the molluscs of the coralligenous habitat has been designed and implemented for the collection and management of this information. From its index compilation more than 511 species of molluscs have been recorded so far from the coralligenous formations, the majority of which belongs to the class Gastropoda (357 sp.) followed by the Bivalvia (137 sp.), Polyplacophora (14 sp.), Cephalopoda (2 sp.) and Scaphopoda (1 sp.). Among these, the gastropod Luria lurida (Linnaeus, 1758) and Charonia lampas (Linnaeus, 1758), the endemic bivalve Pinna nobilis Linnaeus, 1758 and the endolithic bivalve Lithophaga lithophaga (Linnaeus, 1758), are protected by international conventions.

PLOS ONE, 2015

Tests of significance were run based on Euclidean distances for square root transformed ... more Tests of significance were run based on Euclidean distances for square root transformed data.*statistically significant differences (p<0.05).Summary of PERMANOVA results for Eunicella cavolini population density.</p

Marine Biodiversity, Feb 26, 2015

In the East Mediterranean, five species of the family Plakobranchidae have been recorded (Koutsou... more In the East Mediterranean, five species of the family Plakobranchidae have been recorded (Koutsoubas and Koukouras 1993; Turkmen and Demirsoy 2009). Elysia gordanae Thompson& Jaklin 1988 is a small elysiid, between 10 and 17 mm in length, and can be found in shallow waters on rocky bottoms. It feeds upon Acetabularia acetabulum (Linnaeus) P.C. Silva 1952 and other filamentous algae. In the summer of 2012, a survey was conducted in the area of Kouremenos in eastern Crete by a team of two divers in order to record the biodiversity of the shallow waters (< 10 m). By means of visual census with free diving, ten dives of two-hour fixed duration were led along predefined transects (Katsanevakis et al. 2012). The findings were recorded on waterproof paper, as this is an ideal means of writing underwater and then transferring the data safely to the laboratory. Whenever necessary, specimens were collected and transferred alive and intact in the laboratory for stereoscopic vision and in situ photography. Among the species, one specimen of Elysia gordanae Thompson & Jaklin, 1988 (Fig. 1) was found in one location. It was semi-buried at a depth of 1 m under the mud on the rocky bottom. Part of the rocky bottom was covered by a dense community of the Actiniaria Anemonia viridis (Forskal, 1775) and Acetabularia acetabulum (Linnaeus) P.C. Silva 1952. This is the first record of Elysia gordanae Thompson & Jaklin, 1988 in the East Mediterranean Sea. Other Opisthobranchia that were abundant in the region were Elysia timida (Risso, 1818) and Thuridilla hopei (Verany, 1853) while a young (60 mm) opisthobranch, Aplysia dactylomela Rang 1828, was recorded crawling among the Cymodocea nodosa (Ucria) Ascherson 1870 meadow that covers part of the gulf. The specimen is deposited in the collection of invertebrates at the Natural History Museum of Crete in 96 % alcohol (NHMC 52.114). This is the easternmost location that has been found, in a particularly oligotrophic sea compared to the type of locality in the northeastern Adriatic Sea and other locations that have been recorded thus far. The species has a color variation due to the muddy bottom, which ultimately prevents researchers and divers from detecting it easily, compared to its white counterpart with red dots known as Elysia timida (Risso, 1818), which is easily located on the rocky bottoms of the shallow waters. More intensive and intrinsically thorough research is likely to show more species that, to date, have never been recorded in the East Mediterranean.

Mediterranean Marine Science, Feb 5, 2019

Coralligenous formations are biogenic structures typical of the underwater Mediterranean seascape... more Coralligenous formations are biogenic structures typical of the underwater Mediterranean seascape. Their intricate, multi-layered species assemblages are composed of perennial, long-lived organisms, particularly vulnerable to natural or human-induced disturbances. Despite their high ecological role and conservation value, few studies have addressed these assemblages outside the NW Mediterranean. This is the first quantitative assessment of coralligenous in the N Aegean Sea (NE Mediterranean), specifically focusing on the upper bathymetric limit of assemblages that are dominated by the yellow gorgonian Eunicella cavolini. The number and percent cover of macrobenthic species were studied at depths of 18 to 35 m, using a photoquadrat method. A total of 99 benthic taxa were identified, out of which 89 perennial ones were used to investigate spatial patterns in assemblage structure, composition, and biodiversity. A mean number of 47 perennial taxa were recorded per site, with encrusting coralline algae and sponges being the dominant groups in percent cover and species number, respectively. Across the studied localities, structural complexity and community composition were overall similar, but assemblages presented distinctive differences at the site level, thus highlighting the role of local abiotic and anthropogenic factors in the shaping of the coralligenous. Compared to the rest of the Mediterranean, assemblages hosted a similar number of taxa. However, the number and percent cover of erect bryozoans were generally low, while, apart from E. cavolini, other erect anthozoan species were absent. This work provides important reference data for comparisons and monitoring at a local or Mediterranean scale.

Bollettino malacologico., 1993

Quaternary International, Dec 1, 2015

Abstract In the Mediterranean Sea, infralittoral and circalittoral rocky bottoms (from 15 to 120 ... more Abstract In the Mediterranean Sea, infralittoral and circalittoral rocky bottoms (from 15 to 120 m) are characterized by a biogenic habitat, named “coralligenous”, formed by the concretion of calcareous organisms, mainly algal thalli, and to a lesser extent by animal skeletons. This complex habitat is inhabited by a rich fauna that belongs to different taxonomic groups. Sponges, bryozoans, cnidarians and ascidians are the most common sessile organisms that inhabit the area, while crustacea and molluscs are the most common mobile organisms. Little information on the diversity of the molluscs that thrive in the coralligenous habitat is known, though this information is highly important for biodiversity management purposes. A database for the molluscs of the coralligenous habitat was compiled and a method implemented for the management of this information. More than 511 species of molluscs have been recorded so far from the coralligenous formations, the majority of which belong to the class Gastropoda (357 sp.) followed by Bivalvia (137 sp.), Polyplacophora (14 sp.), Cephalopoda (2 sp.) and Scaphopoda (1 sp.). Among these, the gastropod Luria lurida (Linnaeus, 1758) and Charonia lampas (Linnaeus, 1758), the endemic bivalve Pinna nobilis (Linnaeus, 1758) and the endolithic bivalve Lithophaga lithophaga (Linnaeus, 1758), are protected by international conventions.

Journal of Natural History, Feb 1, 2008

This study investigates the multivariate spatio‐temporal population patterns of molluscan taxocoe... more This study investigates the multivariate spatio‐temporal population patterns of molluscan taxocoenosis along an organic load gradient caused by the presence of a fish farm unit in the semi‐enclosed micro‐tidal Gera bay in the island of Lesvos (northeast Aegean), by exploring three different properties (species abundance, trophic web structure and geographic ranges) as indicators for detecting community disturbance. Results have shown that community properties related to ecosystem functioning (i.e. food web analysis) and macro‐ecological aspects (i.e. zoogeographical orientation community features) have proved to be more sensitive in detecting the effects of organic load perturbation than species abundance, thus indicating the use of such properties in environmental assessment approaches in the future.

The aim of this work was to survey the early history of bivalve mollusc exploitation and consumpt... more The aim of this work was to survey the early history of bivalve mollusc exploitation and consumption in the Mediterranean coastal areas as recorded in the classical works of Greek antiquity. All bivalve species mentioned in the classical texts were identified on the basis of modern taxonomy. The study of the works by Aristotle, Hippocrates, Xenocrates, Galen, Dioscorides and Athenaeus showed that out of the 35 exploited marine invertebrates recorded in the texts, 20 were molluscs, among which 11 bivalve names were included. These data examined under the light of recent information on bivalve exploitation showed that the diet of ancient Greeks included the same bivalve species consumed nowadays in the coastal areas of the Mediterranean. The habitats of the exploited bivalves and consequently their fishing areas were well known and recorded in the classical texts. Information on the morphology and various aspects of the biology of certain edible species was given mostly in Aristotle's zoological works, while Xenocrates and Athenaeus presented instructions and recipes on how bivalves were cooked and served. Hippocrates and Galen gave detailed information on the dietary value of bivalve molluscs, their consumption for treatment or prevention of certain diseases, and their use for the production of drugs from their shell or flesh. The data on bivalve use derived from the classical texts is in accordance with archaeological evidence of the geometric and archaic periods from Greek coastal localities.

Hydrobiologia, Aug 4, 2018

Bollettino malacologico., 1991

Marine Ecology Progress Series, Jul 12, 2013

Hydrobiologia, Mar 25, 2011

Estuarine Coastal and Shelf Science, Jul 1, 2018

Journal of Experimental Marine Biology and Ecology, Sep 1, 2012

ABSTRACT Cited By (since 1996): 1, Export Date: 16 January 2013, Source: Scopus, CODEN: JEMBA, do... more ABSTRACT Cited By (since 1996): 1, Export Date: 16 January 2013, Source: Scopus, CODEN: JEMBA, doi: 10.1016/j.jembe.2012.05.016, Language of Original Document: English, Correspondence Address: Dimitriadis, C.; Dept. of Marine Sciences, Faculty of Environment, University of the Aegean, Lesvos Island 81100, Greece; email: xdimitriadis@marine.aegean.gr, References: Basset, A., Sabetta, L., Sangiorgio, F., Pinna, M., Migoni, D., Fanizzi, F., Barbone, E., Beqiraj, S., Biodiversity conservation in Mediterranean and Black Sea lagoons: a trait-oriented approach to benthic invertebrate guilds (2008) Aquat. Conserv. Mar. Freshwat. Ecosyst., 18, pp. 4-15;

2nd Mediterranean Symposium on the Conservation of Coralligenous and other Calcareous Bio-Concret... more 2nd Mediterranean Symposium on the Conservation of Coralligenous and other Calcareous Bio-Concretions, 29-30 October 2014, Portorož, Slovenia.-- 2 pages, 1 figure

Acta Adriatica: International Journal of Marine Sciences, Jun 21, 2017

Length-weight relationships are presented for 9 commercial fish species from Psara Island (North ... more Length-weight relationships are presented for 9 commercial fish species from Psara Island (North Aegean Sea). The species studied are Boops boops, Dentex maroccanus, Helicolenus dactylopterus, Merluccius merluccius, Mullus surmuletus, Pagrus pagrus, Raja clavata, Scyliorhinus canicula and Trachurus picturatus. To our knowledge, there are no published data on the fish stocks of the study area. Estimates of LWR parameters are provided for Dentex maroccanus, Trachurus picturatus and Helicolenus dactylopterus, for which reliable LWR datasets are few in the literature, while none has been published for the Greek seas. The samples were collected from the continental shelf and the upper slope, by using non-selective fishing gear (with a research vessel and a commercial bottom trawler), during two seasonal sampling periods: November 2009 and May 2010. The growth pattern of Boops boops and Scyliorhinus canicula was found to be positive allometric, whereas an isometric growth pattern was determined for the other species in the study. We hope that the LWR obtained here will be used in future fisheries management or conservation research in the study area, for example, to convert lengths to weights, determine fish condition and assess spatial or temporal variability in fish growth.