PhD Arthur Decae 2010 - Ghent Ecology - Universiteit Gent

Material and Methods
In order to evaluate the origin and affinities of the Mediterranean mygalomorph fauna, two
basic questions have to be answered: 1) which species do exist in the Mediterranean and 2)
where are they to be found To answer these questions at, the species level, extensive and
detailed taxonomical revision is necessary for all Mediterranean genera although the
information presented in the forgoing chapters on Nemesia, Iberesia, Ummidia and
Cyrtocarenum may be regarded as promising first steps. Much work remains to be done even
at a basic level of species discovery and description. At the family and genus levels some
insight is given here in the form of a quick identification key to Mediterranean genera and a
set of distribution maps (see below). The necessary data on the distribution and diversity were
collected in a survey of the extant literature, museum collections and large private and
institutional collections from regions all over the area of interest. A total of 1430 locations
were thus far recorded (Table 2) to produce the distribution maps (Figs.1-13). Over 600
specimens of this sample, including representatives of all Mediterranean genera, were
morphologically studied with the aid of a Ceti-Medo 2 binocular microscope in order to
assess diagnostic taxonomical characters necessary for taxonomic revision. The result of this
survey is summarized in the key given below. The collected information on the geographic
origin of all specimens studied was amassed in a Microsoft Access Data Base and analyzed
for distribution and diversity with the aid of DIVA-GIS geographical computer program
(Hijmans et. al. 2005). The resulting distribution maps are shown in Figs.1-13. In order to
study the affinities of the Mediterranean mygalomorph fauna with that of distributions of
related Mygalomorphae the mapped results were compared with biogeographical information
as it is reported in the Word Spider Catalog (Platnick 2010). Inset maps indicate distributions
of related taxa outside the Mediterranean. The hatched regions only indicate the countries for
which the relevant taxa are recorded in the WSC (Platnick 2010).
Results
Key to Mediterranean Mygalomorph Genera
1) Spinneret number six………………………………………………. Atypus
two……………………………………………… Iberesia
four…………………………………………… 2)
2) Claw tufts present, 3 rd claw absent (paired claws present) ……... 3)
Claw tufts absent, 3 rd claw present ……………………..……………... 4)
3) Occular process present, male tibia I unmodified …….………………. Ischnocolus
Occular proces absent, male tibia I male with spur …..………………. Chaetopelma
4) Dense scopula on anterior tarsi and metatarsi …………………….. 5)
Scopulae anterior tarsi and metatarsi absent (or very thin in males only) 6)
5) Occular process absent ............................................................ Cyrtauchenius
Occular process present ……………………………………… 7)
6) Dense spinefields on anterior tarsi and metatarsi, spinnerets short 9)
Dense spinefields absent, PLS very long PMS wide apart
Macrothele
7) PLS short, distal segment domed, PMS close together Nemesia
PLS long, distal segment digitiform, PMS wide apart 8)
8) Males tibia I with distal spur carrying twin hooks Brachythele
Male tibia without spur (only distal spines)
Raveniola
9) Eye-group split, ALE placed separately and far forward Idiops
Eye-group not split, much wider than long, occular process absent, Cyrtocarenum
Eye-group compact roughly rectangular, slight occular proces present 10)
10) Tibia III with saddle depression ……………………………………… Ummidia
Tibia III without saddle ………………………………………. Cteniza