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New Records for Europe: Argiope trifasciata (Forsskål, 1775) from Italy and Malta (Araneae, Araneidae)

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  • Tergeste Power and Propulsion srl

Abstract and Figures

Both the actual finding of several specimens and numerous photographic reports allow us to ascertain for the first time in Italy, precisely in the Mediterranean areas of Sicily and Sardinia, and in Malta, the presence of Argiope trifasciata (Forsskål, 1775) (Araneae, Araneidae). With the help of habitus and genital macro photographs, the collected specimens are described and compared with the other congeneric European species. General ecology and European distribution are also discussed.
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Bulletin of the British Arachnological Society (2011) 15 (6), 205–208 205
New records for Europe: Argiope trifasciata
(Forsskål, 1775) from Italy and Malta (Araneae,
Araneidae)
Piergiorgio Di Pompeo*
Pescara (PE), Italy.
email: piergiorgio.dipompeo@alice.it
Alessandro Kulczycki*
Roma (RM), Italy.
email: alessandro.kulczycki@hotmail.it
Carlo Maria Legittimo*
Città della Pieve (PG), Italy.
email: carlomarialegittimo@yahoo.it
Enrico Simeon*
Cervignano del Friuli (UD), Italy.
email: enricosimeon@yahoo.it

Summary
        

Italy, precisely in the Mediterranean areas of Sicily and Sardinia,
and in Malta, the presence of Argiope trifasciata (Forsskål,
1775) (Araneae, Araneidae). With the help of habitus and genital
macro photographs, the collected specimens are described and
compared with the other congeneric European species. General
ecology and European distribution are also discussed.
Introduction
The family Araneidae is currently the third largest family
of spiders. It presently contains 168 genera and 3006 species
(Platnick 2011) widely distributed around the world. Within
this family, Argiope Audouin, 1826 is one of the most
familiar and extensively studied genera. The 78 currently
described species (Platnick 2011) occur on all continents
except Antarctica, mainly in the tropical and subtropical
zones.
Since the second half of the 1700s, two species have
been known for Europe, both of which also occur on Italian
and Maltese territory. Argiope bruennichi (Scopoli, 1772)
is recorded for most European countries with exceptions
such as Ireland, Albania, and Bosnia (van Helsdingen
2011). However, considering the favourable climatic and
ecological conditions of the last two, the apparent absence
of this species is probably due to lack of data. The second
European species, Argiope lobata (Pallas, 1772), being
relatively more xero-thermophilic, is limited to southern
Europe. It occurs on all Black Sea and Mediterranean facing
countries including North Africa, and reaches into southern
Russia. During the early 1900s a third European species
was described and recorded for Portugal: Argiope acumi-
nata Franganillo, 1920. However, it has never been seen or
collected since then and therefore we consider it potentially
invalid.
It was not until 1985 (Morano & Ferrández 1985; van
Helsdingen 2011) that Argiope trifasciata (Forsskål, 1775),
the Egyptian holotype (Cairo) of which has been lost, was

a widespread species with a cosmopolitan distribution, it
was previously known to occur on several archipelagos of
the southern Atlantic coast (such as Madeira and the Canary
Islands) but thought to be absent from the European conti-
nent (Levi 1983, 2004; Platnick 2011). It was, however,
collected from the south-eastern Spanish mainland (Morano
& Ferrández 1985) and, more recently, from southern
Portugal and the Balearic Islands (Cardoso & Morano 2010).
With these new records of A. trifasciata from insular Italy
and Malta we bring a new addition to the spider faunas of
both countries, extending its known European distribution.
Figs. 1–3: European species of Argiope, 1 A. trifasciata; photo by Antonino La Spina; 2 A. lobata; photo by Gioele Tropea; 3 A. bruennichi; photo
by Emanuele Biggi.
123
ISSN 2049-3045
206 Argiope trifasciata from Italy and Malta

Island, November 2009.
The genus Argiope is, among the Araneidae, easily distin-
guishable by its overall morphology, the usually striking
abdominal markings (Figs. 1–3), and the typical eye pattern,
the posterior row of which is strongly procurved (Roberts
1995; Levi 2004). Considering these factors, all specimens
observed, both preserved and photographed (see Fig. 9 for
distribution map), can easily be assigned to the genus.
A. trifasciata is readily distinguished from A. lobata by
the obvious differences in habitus and abdominal pattern,
and especially by the lack of the distinctive abdominal lobes
(Fig. 2) which surround its edge in the latter (Levi 1983). In
contrast, A. bruennichi (Fig. 3) is similar to A. trifasciata in
terms of abdominal morphology but can be differentiated
from the latter by both dissimilarities in abdominal mark-
ings and in the number and intensity of leg bandings. While
differences between these two species are minor compared
to those which discern A. lobata, they are still easily notice-

Analysis and observations
Habitus and genital traits of the collected specimens were
compared with Levi’s descriptions (1968, 1983, 2004). Both
appeared to be particularly coherent with the traits of Egyp-
tian specimens described in 1968, especially the epigyne
which coincides perfectly. Photographic reports from Sicily
and Malta allow us to positively identify the specimens
without any doubt as A. trifasciata   
photographs clearly show both the typical habitus and espe-
cially the unique shape of the genitalia which effectively
matches the one we observed in the analysed specimens.
Material and methods
The collected specimens are preserved in 75% alcohol,
while the egg sacs are kept dry. Both the specimens and the
egg sacs are preserved among the authors’ private collec-
tions. Specimens were examined using a Leica MZ16 stereo-
microscope. Measurements are in millimetres (mm) and are
presented as: femur–patella–tibia–metatarsus–tarsus (total).
Results
Argiope trifasciata (Forsskål, 1775)
        
Regionale Molentargius Saline, Is Arenas, (Cagliari),
39°13'16.41"N, 9°9'49.62"E, September 2010, R. Rattu leg.;

9°10'36.57"E, August 2010, S. Piredda leg.

       

      
Fig. 4: Argiope trifasciata -
targius Saline (CA): ventral view.
Fig. 5: Argiope trifasciata -
targius Saline (CA), epigyne: a ventral view; b lateral view.
Fig. 6: Argiope bruennichia ventral
view; b lateral view.
a b
a b
P. Di Pompeo, A. Kulczycki, C. M. Legittimo, E. Simeon 207
Dorsally, the oval abdomen is transversed by a series of
white and pale yellow bands, separated by thin black stripes
(Fig. 1). The bandings are quite orderly compared to the
irregular appearance of the ones observed in A. bruennichi
(Fig. 3). In addition, the black leg annulations, as opposed
to the latter, are more intense and extend into the femur,
especially on its ventral side (Fig. 4).
The epigyne (Fig. 5) is substantially different from
that of A. bruennichi (Fig. 6) which lacks a septum. The
sclerotized plate is raised anteriorly, forming a large bulge
which laterally borders the two genital openings. Posteri-
orly, the septum folds into two circular expansions which

anterior raised part of the septum overhangs the rim of the
anterior bulge, instead of being fused with it. The septum
terminates anteriorly with a distinctive bifurcation.
The body length of the three analysed females varied
between 14 mm and 17 mm according to the degree of
abdominal swelling. The size of the carapace, however, was
generally consistent in all three, measuring 6 mm in length
and 5 mm in width. We report the following leg measure-
       
L1—8.5–3.0–6.0–8.0–2.0 (27.5); L2—8.1–2.5–5.4–8.8–2.0
(26.8); L3—4.8–1.3–2.8–4.5–1.5 (14.9); L4—8.0–2.8–4.7–
8.0–2.0 (25.5).
At the present time, no adult male has been collected.
Four egg sacs were found in close proximities to the
webs of several adult females. These were anchored to
the surrounding vegetation by several tough suspension
threads and measured approximately 20 mm in height and
had a width ranging from 7 mm to 15 mm in the widest
part. Their appearance (Fig. 7) is quite distinctive and is
noticeably different from that of the spherical egg sacs of A.
bruennichi. All have a polygonal shape, bounded by straight
margins. The periphery of each egg sac is conspicuously
thickened and serves as the starting point for the numerous
attachment threads which support it. One of the sides, which
 
instead strongly convex and contains the eggs and the egg
chamber. The whole structure is enveloped in a tough outer
layer of olive-coloured silk which aids in crypsis. Addition-
ally, from one of the egg sacs hatched several hundred spid-
erlings which measured approximately 1mm in body length.
Notes on ecology, habitat and European distribution
Most sightings and most of the collected specimens come
from coastal areas of the Gulf of Cagliari, southern Sardinia,
where the climate is markedly Mediterranean. Although
Fig. 7: Argiope trifasciata, Sardinia: Parco Naturale Regionale Molentar-
gius Saline (CA), egg sac: a front view; b posterior view; c lateral
view.
there is microhabitat heterogeneity throughout the region,
A. trifasciata appears to be a generally thermophilic sun-
loving species. Webs are built among the dense Mediterra-
nean shrubland, which typically consists of psammophytes,
xerophytes (Salicornia sp., Arthrocnemum sp., Salsola sp.)
and occasionally rushes (Juncus sp.). The collected females
had built their large stabilimentum-bearing orbwebs among
the lower layers of the shrubland, between the lower bushes
and the taller graminoids (Fig. 8).
Two specimens were photographed in Sicily, in the close
proximity of the nature reserve of Bosco di Santo Pietro,
Caltagirone (CT). Vegetation here is more heterogeneous
and consists of Mediterranean shrubland and garrigue,
numerous xerophytes (Thymus sp.) and occasional oak trees
(Quercus suber). The climate of this area is still Mediter-
ranean and, even though the level of humidity is slightly
higher, in terms of average temperatures it does not differ
from the coastal areas of Sardinia. A third specimen was
recorded near Siracusa (SR), an area of lower altitude and of
closer proximity to the coastline compared to Bosco Santo
Pietro.
In Malta, this species has been recorded from an open
-
tion and tall graminoids. This zone lies in close proximity
to an urban area and has, therefore, been colonized also by
several ruderal species. Overall, climatic conditions are
generally similiar to those observed in Sicily and Sardinia.
All areas share similar mild winters: minimum temperatures
practically never drop below 0°C and frosts do not occur.
Compared to the other two European species, A. trifas-
ciata        
Mediterranean habitats, being frequent in coastal and low
altitude areas. It is, therefore, absent from regions with
frequent frosts and freezes. This is coherent with what is
known for the rest of its limited European distribution,
such as southern Portugal and south-eastern Spain (Morano
& Ferrández 1985; Cardoso & Morano 2010). Due to the
presence of several climatically homogeneous areas of
southern Europe, such as the southern Italian mainland, the
Aeolian Islands, southern Greece and western Turkey, we
also believe that its current restricted range could indeed
Fig. 8: Sardinia: Parco Naturale Regionale Molentargius Saline (CA), a
typical Mediterranean habitat composed of xerophytes, shrubs and
sporadic trees; photo by Roberto Rattu.
a b c
208 Argiope trifasciata from Italy and Malta
for their photos. Special thanks go to Prof. Paolo Tongiorgi

passion with us.

of Dr Ilic Farabegoli and Prof. Claudio Arnò, founders of
the Associazione Italiana di Aracnologia, always helpful
      
      
knowledge on arachnids.
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be wider. With future targeted samplings we are willing to
ascertain if this is the case.
Conclusions
The observations we made on our analysed specimens
       
some of the areas, including that of mature females with egg
sacs, allow us to safely ascertain the presence of A. trifas-
ciata in Sicily, Sardinia, and Malta. We believe that, due to
its large, striking, and easily distinguishable appearance, the
chances for it to have gone unnoticed from the 1700s until
today are extremely low. However, we cannot completely
rule out the possibility of it being a long-established species
      
as A. bruennichi in the past. Nevertheless, we consider
A. trifasciata to be recently introduced and naturalized to

Aknowledgments
We wish to thank Dr Roberto Rattu and Stefania
Piredda for their kindness and for the invaluable material
they provided. We also thank Prof. Mauro Tretiach and Dr
Giuseppe Crimaldi for their availability, Emanuele Biggi,
Antonio La Spina, Albert G. Floridia and Gioele Tropea
Fig. 9: Distribution map showing records of Argiope trifasciata -

... The genus Argiope Audouin (1826) is widely recognized and extensively studied within the Araneidae. There are presently 78 documented species that inhabit all continents except Antarctica, mainly in the tropical and subtropical areas (Di Pompeo et al., 2011). The species A. lobata (Pallas, 1772) was originally recorded in the Sinjar district of Mosul province, northern Iraq by Reimoser (1913). ...
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... to the detection of allochthonous species (e.g., Di Pompeo et al. 2011, Kulczycki et al. 2012, Nardi et al. 2019, Pantini et al. 2020. DNA barcoding relies on the analysis of a specific small genomic region (for metazoans usually a fragment of the mitochondrial cytochrome c oxidase subunit 1) for molecular species identification. ...
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