Nemastomatidae
Nemastoma bimaculatum, damaged some legs
Fadenkanker ( Nemastomatidae ) are a family of harvestmen ( Opiliones ). The division into classes according to genitalmorphologischen criteria was achieved only after the work of Roewer (1951 ), who then assigned yet most species of a genus Nemastoma, which is the richest in this family even today.
Features
The Fadenkanker reach depending on a length of one to six millimeters. Most species are characterized by very long and thin pedipalps. Their chelicerae are of average size. The length of the legs varies within a wide range between species.
Occurrence
The family has a disjoint holarktisches distribution area. Great abundance of forms they reached the subfamily Nemastomatinae the west of the Palearctic. Here it is widespread throughout Europe to Iceland. Many species live in limited areas in mountains of more southern latitudes, such as the Caucasus, Atlas, North Africa, from Anatolia to the northern Iran and partly also in Central Asia to the Himalayas.
To the east of the Palearctic and Nearctic in the form of wealth is lower, living there Fadenkanker belong to the subfamily Ortholasmatinae. They live on both coasts of the Pacific, on the one hand, on the west coast of North America between Mexico and British Columbia in Canada, on the other hand, in East Asia (Japan and northern Thailand ).
In Europe, this family is represented by 56 species, Central Europe has 17 species in Germany are so far only nine species from four genera detected, including Nemastoma bimaculatum, the Eastern Silberfleckkanker ( Nemastoma lugubre ) and the Einzahnmooskanker ( Nemastoma dentigerum ). In the Alps, some species are endemic, including the Alpine Fadenkanker ( Mitostoma alpinum) and the Black Two mandrel ( Paranemastoma bicuspidatum ).
Way of life
The Fadenkanker feed on insects and mites. They usually live near the ground under wood, leaves or stones. Often they are found in mountainous areas, where the area of distribution of individual species is restricted to this mountain.
System
The oldest fossil discovery of a copy of which can be attributed to the family of Fadenkanker, dates from the Cretaceous ( Albian ) around 100 million years ago. The well-known by a Fund from Myanmar amber species was described in 2005 by Gonzalo Giribet and Jason A. Dunlop under the name Halitherses and assigned to the subfamily Ortholasmatinae. An elderly Fund from the Permian ( Rotliegend of Gold FCK layers in Friedrichroda ) from Thuringia and also provided by Erstbeschreiber 1957 the Fadenkankern, but is poorly described and it has been suggested later that it was the fossil is not a harvestman, but vegetable material is.
In contrast to many other families of harvestmen the Fadenkanker be phylogenetically regarded as monophyletic. The family is divided into two subfamilies, of which the Nemastomatinae include most genres. A total of 19 genera with about 170 species are currently described:
- Nemastomatinae Acromitostoma
- Buresiolla
- Carinostoma
- Caucnemastoma
- Centetostoma
- Giljarovia
- Hadzinia
- Historicostoma
- Mediostoma
- Mitostoma
- Nemaspela
- Nemastoma
- Nemastomella
- Paranemastoma
- Pyza
- Vestiferum
- Ortholasmatinae Dendrolasma Banks, 1894
- Martensolasma Shear, 2006
- Ortholasma Banks, 1894
- Halitherses Giribet & Dunlop, 2005 ( fossil from an amber discovery from the Cretaceous period, age about 100 million years)
- Incertae sedis Rhabdotarachnoides (fossil layers from the Permian, possibly but there are plant residues)