Calathocratus Simon, 1879
The genus comprises small- to medium-sized trogulids characterized by one-segmented tarsi of legs II but higher tarsal counts in other legs. It includes the former genera Platybessobius and Trogulocratus which, like Calathocratus, were formerly defined upon distinct tarsal counts but found to be para- and/or polyphyletic (Schönhofer and Martens 2010). Many species share an undulating area of missing papillation on the median line of the body and crests of elongated, parallel papillae at the joints of some leg segments. Little is known about these rare and cryptic animals which show a disjunct distribution around the Mediterranean Sea and reach as far East as the Caucasus (Šilhavý 1966) and Kyrgyzstan. The distribution seems to follow the ancient borders of the Tethys Sea.
Taxonomy and Discussion of Phylogenetic Relationships
Genetic distances between populations are large, suggesting limited dispersal abilities and many small scaled endemics, a pattern not expressed in morphology. The number of cryptic species might be many times higher than presently known. Phylogenetic relationships within the group seem to be better expressed by geographic proximity rather than by morphological similarity (Schönhofer & Martens 2010). In view of a necessary revision and uncertainty of species delimitation the presented tree was not further resolved.
Ecology and Life History
Species can be sieved from leaf litter in a variety of different forest types including oak, conifer and Mediterranean evergreen broad-leafed forest, but they are also recorded from under stones in more open habitats. They seem to have a preference for higher temperatures as most records are from low altitudes and southern distributions except for the Italian species present in mountainous snowfall regions. Ecologically, they probably substitute for small-bodied Trogulus species that seem mostly absent in the distribution area of Calathocratus.
References
Schönhofer, A. L. and J. Martens. 2010. Hidden Mediterranean diversity: Assessing species taxa by molecular phylogeny within the opilionid family Trogulidae (Arachnida, Opiliones). Molecular Phylogenetics and Evolution 54 (1):59-75.
Šilhavý, V. 1966. Neue Troguliden aus dem Kuban-Gebiet und dem Kaukasus (Arach., Opiliones). Senckenbergiana biologica 47 (2):151-154.
Credits
Page created by Axel L. Schönhofer. Dave Carlson helped improve the English.
Taxonomy and Discussion of Phylogenetic Relationships
Genetic distances between populations are large, suggesting limited dispersal abilities and many small scaled endemics, a pattern not expressed in morphology. The number of cryptic species might be many times higher than presently known. Phylogenetic relationships within the group seem to be better expressed by geographic proximity rather than by morphological similarity (Schönhofer & Martens 2010). In view of a necessary revision and uncertainty of species delimitation the presented tree was not further resolved.
Ecology and Life History
Species can be sieved from leaf litter in a variety of different forest types including oak, conifer and Mediterranean evergreen broad-leafed forest, but they are also recorded from under stones in more open habitats. They seem to have a preference for higher temperatures as most records are from low altitudes and southern distributions except for the Italian species present in mountainous snowfall regions. Ecologically, they probably substitute for small-bodied Trogulus species that seem mostly absent in the distribution area of Calathocratus.
References
Schönhofer, A. L. and J. Martens. 2010. Hidden Mediterranean diversity: Assessing species taxa by molecular phylogeny within the opilionid family Trogulidae (Arachnida, Opiliones). Molecular Phylogenetics and Evolution 54 (1):59-75.
Šilhavý, V. 1966. Neue Troguliden aus dem Kuban-Gebiet und dem Kaukasus (Arach., Opiliones). Senckenbergiana biologica 47 (2):151-154.
Credits
Page created by Axel L. Schönhofer. Dave Carlson helped improve the English.
