Centetostoma Kratochvíl, 1958
©map: Axel Schönhofer; data for distribution map derived from Marcellino (1975) Martens (1978, 2011) and own collection data (ATBI+M).
Centetostoma comprises four small to very small (1.3-1.9 mm) and short legged European species from the Pyrenees (Spain and France) and the south-western Alps (France and Italy). Genus characteristics are the male genital morphology with a blunt stylus, split basis of the penis and typical wings on the upper penial truncus in form of large pockets or widely outstretched wing-like arms. The males have cheliceral apophyses partly bent over in the distal part, and species are identified upon the characteristic structure of the apophyses and the form of the penis. Distribution of the species in the Pyrenees partly overlaps. Coloration is uniform brown to blackish with the body and the legs covered with large granules.
Taxonomy and Discussion of Phylogenetic Relationships
Originally described as monotypic subgenus Centetostoma for centetes, Martens (1978) included Nemastoma of the bacilliferum-group as understood by Dresco (1967) and Rambla (1968) within Centetostoma. In 1986, Starega assigned the older available name Nemastomella to this assembly and gave a full list of species but mentioned centetes as relatively isolated. Martens (2011) resolved this heterogeneity by redefining Centetostoma to comprise now four species, adding three Pyrenean ones taxonomically neglected till then. There remains some uncertainty if centetes in that constellation may not still be closer related to Nemastomella than the other Centetostoma species (Martens 2011) which could sink Centetostoma into Nemastomella again.
Ecology and Life History
All specimens inhabit sub-montane to alpine habitats, from open forest and forests at the tree-line, to bare alpine meadows. In the Alps 1500-2100 m, in the Pyrenees 1000-2800 m are recorded. They prefer stones as resting places under which they can be collected. At night they can be found walking around, e.g. on mossy bases of trees. The Pyrenean species can be quite abundant and several specimens may be found under one stone, while the alpine Centetostoma centetes is quite rare, found mostly in single individuals and is generally hard to locate (Marcellino 1975, Martens 1978). Juveniles are virtually absent from collections, which date only from midsummer to late autumn.
References
Dresco, E. 1967. Nemastoma bacilliferum Simon. Espèces voisines, espèces nouvelles. Annales de Spéléologie 22 (2):367-391.
Kratochvíl, J. 1958. Höhlenweberknechte Bulgariens (Palpatores - Nemastomatidae). Práce Brnenské základny Ceskoslovenské akademie ved 30 (12):523-576.
Marcellino, I. 1975. Opilioni (Arachnida) delle alpi occidentali. Bollettino del Museo Civico di Storia Naturale di Verona 2:119-144.
Martens, J. 1978. Spinnentiere, Arachnida - Weberknechte, Opiliones. Die Tierwelt Deutschlands 64:1-464.
Martens, J. 2011. The Centetostoma scabriculum complex - a group of three cryptic species (Arachnida: Opiliones: Nemastomatidae) Zootaxa 2783:35-51.
Rambla, M. 1968. Las especies del grupo Nemastoma bacilliferum Simon 1879 en la Península Ibérica (Opiliones, Fam. Nemastomatidae). Publicaciones del Instituto de Biologia Aplicada 45:33-56.
Starega, W. 1986. Eine neue Art der Nemastomatidae (Opiliones) aus dem Pamir, nebst nomenklatorisch-taxonomischen Anmerkungen. Bulletin de l'Académie Polonaise des Sciences, Varsovie, Cl. II, Série des Sciences Biologiques 34 (10-12):301-305.
Credits
Page created by Axel L. Schönhofer. Angela DiDomenico helped improve the English.
Centetostoma comprises four small to very small (1.3-1.9 mm) and short legged European species from the Pyrenees (Spain and France) and the south-western Alps (France and Italy). Genus characteristics are the male genital morphology with a blunt stylus, split basis of the penis and typical wings on the upper penial truncus in form of large pockets or widely outstretched wing-like arms. The males have cheliceral apophyses partly bent over in the distal part, and species are identified upon the characteristic structure of the apophyses and the form of the penis. Distribution of the species in the Pyrenees partly overlaps. Coloration is uniform brown to blackish with the body and the legs covered with large granules.
Taxonomy and Discussion of Phylogenetic Relationships
Originally described as monotypic subgenus Centetostoma for centetes, Martens (1978) included Nemastoma of the bacilliferum-group as understood by Dresco (1967) and Rambla (1968) within Centetostoma. In 1986, Starega assigned the older available name Nemastomella to this assembly and gave a full list of species but mentioned centetes as relatively isolated. Martens (2011) resolved this heterogeneity by redefining Centetostoma to comprise now four species, adding three Pyrenean ones taxonomically neglected till then. There remains some uncertainty if centetes in that constellation may not still be closer related to Nemastomella than the other Centetostoma species (Martens 2011) which could sink Centetostoma into Nemastomella again.
Ecology and Life History
All specimens inhabit sub-montane to alpine habitats, from open forest and forests at the tree-line, to bare alpine meadows. In the Alps 1500-2100 m, in the Pyrenees 1000-2800 m are recorded. They prefer stones as resting places under which they can be collected. At night they can be found walking around, e.g. on mossy bases of trees. The Pyrenean species can be quite abundant and several specimens may be found under one stone, while the alpine Centetostoma centetes is quite rare, found mostly in single individuals and is generally hard to locate (Marcellino 1975, Martens 1978). Juveniles are virtually absent from collections, which date only from midsummer to late autumn.
References
Dresco, E. 1967. Nemastoma bacilliferum Simon. Espèces voisines, espèces nouvelles. Annales de Spéléologie 22 (2):367-391.
Kratochvíl, J. 1958. Höhlenweberknechte Bulgariens (Palpatores - Nemastomatidae). Práce Brnenské základny Ceskoslovenské akademie ved 30 (12):523-576.
Marcellino, I. 1975. Opilioni (Arachnida) delle alpi occidentali. Bollettino del Museo Civico di Storia Naturale di Verona 2:119-144.
Martens, J. 1978. Spinnentiere, Arachnida - Weberknechte, Opiliones. Die Tierwelt Deutschlands 64:1-464.
Martens, J. 2011. The Centetostoma scabriculum complex - a group of three cryptic species (Arachnida: Opiliones: Nemastomatidae) Zootaxa 2783:35-51.
Rambla, M. 1968. Las especies del grupo Nemastoma bacilliferum Simon 1879 en la Península Ibérica (Opiliones, Fam. Nemastomatidae). Publicaciones del Instituto de Biologia Aplicada 45:33-56.
Starega, W. 1986. Eine neue Art der Nemastomatidae (Opiliones) aus dem Pamir, nebst nomenklatorisch-taxonomischen Anmerkungen. Bulletin de l'Académie Polonaise des Sciences, Varsovie, Cl. II, Série des Sciences Biologiques 34 (10-12):301-305.
Credits
Page created by Axel L. Schönhofer. Angela DiDomenico helped improve the English.
