Page 1 - BIR_2017_Balistreri_etal

BioInvasions Records (2017) Volume 6, Issue 1: 19–24
Open Access
DOI: https://doi.org/10.3391/bir.2017.6.1.04
© 2017 The Author(s). Journal compilation © 2017 REABIC

Rapid Communication

Further spread of the venomous jellyfish Rhopilema nomadica
Galil, Spannier & Ferguson, 1990 (Rhizostomeae, Rhizostomatidae)
in the western Mediterranean

4
3,
Paolo Balistreri *, Alessandro Spiga , Alan Deidun *, Sonia Km Gueroun and
1,
2
4
Mohamed Nejib Daly Yahia
1 Vicolo Giotto 6, 91023 Favignana, Italy
2 Strada 41, 09012 Capoterra, Italy
3 Department of Geosciences, University of Malta, Msida MSD 2080, Malta
4 Faculty of Sciences of Bizerte, Laboratory of Aquatic Systems Biodiversity and Functioning, 7021 Zarzouna Bizerte,
University of Carthage, Tunisia
*Corresponding authors
E-mail addresses: requin.blanc@hotmail.it (PB), alan.deidun@um.edu.mt (AD)
Received: 22 September 2016 / Accepted: 9 December 2016 / Published online: 22 December 2016
Handling editor: Stelios Katsanevakis

Abstract
The present paper documents the further spread of the venomous scyphomedusa Rhopilema nomadica Galil, Spannier & Ferguson, 1990,
which first appeared in the Mediterranean off the Israeli coast in the mid-1970s. This report provides the northernmost and westernmost
record of the species in the Mediterranean—from the eastern coast of the Italian island of Sardinia—based on a new record of the species
within the Sicily Channel (Aegadian Islands) and provides evidence of its further establishment within Tunisian coastal waters.
Key words: non-indigenous, scyphomedusa, new records, spread

Introduction 2006; Zenetos et al. 2010), R. nomadica has also
been documented as one of the most impacting
Rhopilema nomadica Galil, Spannier & Ferguson, species in European Seas (Katsanevakis et al. 2014).
1990 (Scyphozoa: Rhizostomeae: Rhizostomatidae) Ever since its first introduction in the eastern
is a tropical scyphozoan that purportedly first entered Mediterranean through the Suez Canal in the late
the Mediterranean Sea via the Suez Canal in the late 1970’s, this Lessepsian newcomer has rapidly
1970’s (Deidun et al. 2011). Rhopilema nomadica expanded westward within the central and western
swarms may have negative impacts on the oligotrophic Mediterranean during the past five years. The species
sea resource (as a planktivorous predator) as well as was successively recorded from Malta (Deidun et al.
on human activities in coastal waters, such as 2011), Tunisia (Daly Yahia et al. 2013), the Italian
aquaculture, fishing and industrial installations and island of Pantelleria (Crocetta et al. 2015), and
tourism (Galil 2007). R. nomadica is venomous and Sardinia (ICES 2016). While this species had only
the active toxic substances contained in jellyfish been occasionally observed in the central and western
nematocysts inflict painful stings on humans, Mediterranean Sea (only scattered individuals have
characterized by erythematous eruptions, itching, been recorded), huge swarms have been recorded
and burning sensations, as well as systematic symp- each summer since the early 1980s along the southeast
toms that include fever, fatigue, and muscular aches Levantine coast (Galil et al. 1990).
(as reviewed in Gusman et al. 1997). Scyphozoa outbreaks depend on multiple environ-
Being labelled as one of the most invasive marine ment factors during the recruitment stage, such as
species in the Mediterranean (Streftaris and Zenetos temperature, light, food quality and quantity, and

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