Taxonomic survey of benthic diatoms in Neum Bay, southeastern Adriatic

Abstract

The objective of this work was to contribute to the knowledge of microphytobenthos in the Adriatic Sea, by studying for the first time the benthic diatom communities in Neum Bay in Bosnia and Herzegovina. For this purpose, the benthic diatoms naturally growing on stones and macroalgae were identified at one station in the small semi-enclosed oligotrophic Neum Bay during 2010 and 2011. A total of 24 samples were collected at two different depths, 0.5 m and 8 m, and analysed with light and scanning electron microscopy. Altogether, 425 pennate and 58 centric taxa (species and infraspecific taxa) belonging to 60 families and 115 genera were noted. Genera with the greatest number of taxa were: Mastogloia (46 taxa), Navicula (36), Diploneis (35), Nitzschia (34), Amphora (31), Cocconeis (27), Achnanthes (14), Halamphora (12), Lyrella (11), and Surirella and Licmophora (10 each). Amphora bigibba var. interrupta and Cocconeis scutellum were the most frequent taxa, being present in 87.5% of the samples. In total, 142 taxa were found only once (sporadic taxa). Although benthic diatom richness is high in the bay, taxa are apparently not distributed evenly temporally. Consistent quantitative and qualitative data are still needed for a better determination of the seasonal and spatial changes of the epilithic assemblages in the region. Cilj rada bio je doprinijeti poznavanju mikrofitobentosa u Jadranskom moru istražujući po prvi put bentoske dijatomejske zajednice u Neumskom zaljevu u Bosni i Hercegovini. Bentoske dijatomeje su određene na jednoj postaji u poluzatvorenom oligotrofnom Neumskom zaljevu 2010. i 2011. Sakupljeno je 24 uzoraka na dubinama 0,5 i 8 m, a analizirani su s pomoću svjetlosnog i skenirajućeg elektronskog mikroskopa. U uzorcima je utvrđeno 425 penatnih i 58 centričnih svojti (vrsta i nižih taksonomskih kategorija) dijatomeja unutar 60 porodica i 115 rodova. Najveći broj svojti nađen je unutar sljedećih rodova: Mastogloia (46 svojti), Navicula (36), Diploneis (35), Nitzschia (34), Amphora (31), Cocconeis (27), Achnanthes (14), Halamphora (12), Lyrella (11) te Surirella i Licmophora (svaki po 10 svojti). Najčešće svojte su Amphora bigibba var. interrupta i Cocconeis scutellum s 87,5% učestalosti u ukupnom broju uzoraka. Utvrđene su 142 sporadične svojte (utvrđene u samo jednom uzorku). Iako je broj svojti relativno visok, nije utvrđena pravilnost u njihovoj vremenskoj raspodjeli. Radi preciznijeg utvrđivanja sezonskih i prostornih promjena strukture epilitskih dijatomejskih zajednica, potrebni su detaljniji kvalitativni i kvantitativni podaci.Ključne riječi: Bacillariophyta, plitki oligotrofni zaljev, taksonomska istraživanja, bogatstvo svojti,

Biodiversity of carapace epibiont diatoms in loggerhead sea turtles (Caretta caretta Linnaeus 1758) in the Aegean Sea Turkish coast

“…Some of the turtles were also observed feeding in the lake and this could be why freshwater taxa were incorporated into the biofilm. Some taxa may be able to tolorate change in salinity (freshwater-brackish, brackish-marine) despite their apparent freshwater preference, and results also support the idea that some species could have different responses to environmental conditions, resulting in a better or worse adaptation ( Underwood, Phillips & Saunders, 1998 ; Ribeiro et al, 2003 ; Miho & Witkowski, 2005 ; Hafner, Jasprica & Car, 2018 ) to variable conditions, which could be explained by the number of the freshwater forms observed on the carapace. It was also suggested by Majewska et al (2017b) that lakes and rivers could make exclusive epibiosis where specific species could attach and grow in the biofilm and environment affects the dispersal on sea turtle carapace.…”

Additions to the Mastogloia (Bacillariophyceae: Mastogloiales) of the Revillagigedo Archipelago, Mexico

“…However, these studies relied on much more complete samplings, whilst in this study for the Revillagigedo Archipelago, the collected material was scarce and thus the sample size much smaller, although not as small as in the previous study (Siqueiros-Beltrones et al, 2019). Elsewhere, the epilithic and epiphytic Mastogloia identified at the Adriatic Sea by Hafner et al (2018) reached 46 taxa using 25 samples gathered for 15 months. Moreover, although the total number of Mastogloia taxa recorded until now for the Revillagigedo Archipelago is closer to the one reported (71) for the southern Gulf of Mexico (Siqueiros-Beltrones et al, 2020), the latter also…”

“…The genus Mastogloia is frequently the most diverse within benthic marine assemblages from warm seas (Hafner et al, 2018;Siqueiros-Beltrones et al, 2020. Currently, 271 species are accepted out of 420 taxa proposed worldwide (Guiry & Guiry, 2021).…”

New Records of Diatoms (Bacillariales, Rhopalodiales & Surirellales) with ultrastructure details from the Black Sea Coast of Turkey

“…Distribution & biogeography: It is a marine species described from the Pacific Ocean (Guiry & Guiry, 2021) and also was observed in the Mediterranean Sea (Hafner et al, 2018). It is observed for the first time in the Sea of Marmara coasts in Turkey (in print).…”