Page 40 - Lo Cascio_2015
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568                                  PIETRO LO CASCIO














































                       Figure 1. Number of species recorded for islands within each ecoregion. The overlapping circles and the
                              relative number correspond to the species in common between different ecoregions.


                   Few islets with a surface less than 1 Km are  chipelago (Japan), but the only species found there
                                                       2
                 home to mutillids, and their localization is gene-  is the same occurring on the nearby Chichi-jima.
                 rally very close to the mainland: Phong Vong (<
                 0.5 Km ) belongs to the small coastal archipelago  Species to genus ratio
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                 of Phu Quoc (southern Viet Nam); Penikese (0.3)
                 lies  in  the  Buzzard  Bay  (Massachusetts,  US);  Species to genus ratio (S/G) has long been re-
                 Embiez  (0.9)  is  a  strongly  anthropized  coastal  cognized as measure of the taxonomic disharmony
                 islet  of  southern  France,  while  Bagaud  (0.45)  of insular faunas (see Gillespie & Roderick, 2002),
                 belongs to the Hyeres Archipelago; Lavezzu (0.7),  but in the case of Mutillidae it seems rather an
                 together with the nearby Cavallo (1.2), belongs to  indirect indicator of how the island faunas are de-
                 an island group not far from the southern coast of  pauperate in comparison to those of the neighboring
                 Corsica, with which it was connected until recent  continental areas.
                 times; Conigli (0.04), that can be considered the  Although not easily verifiable for many of the
                 smaller example of viable surface, represents a  islands listed in Table 1, due to the uncertainties that
                 fragment  of  the  adjacent  Lampedusa  Island  still concern the status of some genera on the whole
                 (Channel of Sicily, Mediterranean) and both were  (such as Ephutomorpha) or their representatives in
                 in  connection  to  North Africa  during  the  Last  some  areas  (e.g.  Trogaspidia  in  the  Malagasy
                 Glacial Maximum.                             region), average S/G is clearly found to decrease on
                   The only tiny oceanic islet inhabited by mutil-  islands when comparing Japan (1.2 ± 0.13) and
                 lids  is  Nishi-jima  (0.49)  in  the  Ogasawara  Ar-  Nansei (1.33 ± 0.23) to China (3.62 ± 0.66: data
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