Family ISOTOMIDAE Schäffer, 1896
Proisotoma brisbanensis
© Copyright J. Thurmer. CSIRO Entomology.
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Family ISOTOMIDAE Schäffer, 1896
Compiler and date details
May 2016 - ABRS on advice from Penelope Greenslade
Penelope Greenslade, School of Botany and Zoology, Australian National University, Canberra, Australian Capital Territory, Australia
Introduction
This database records 55 species in 25 genera in this family. Two of the genera and 23 species are currently endemic to Australia. The endemic genera, Skadisotoma Greenslade & Fjellberg, 2015 and Chionobora Greenslade & Potapov, 2015, are both found at high altitudes in the southern part of the continent. Azeritoma Greenslade & Potapov, 2008, was, until recently, thought to be endemic to Macquarie Island but has recently been recorded from New Zealand (Babenko & Minor 2015). Twenty-one species are currently considered endemic but there are many more species to be described, particularly in the genus Folsomides which is diverse in arid areas.
Tomocerura Wahlgren, 1901 is now considered not to be represented by any described species in Australia (Greenslade 1989). Specimens determined by Womersley (1934, 1939) as Isotomurus chiltoni (Carpenter, 1925) are likely to be misidentifications and have been determined (Greenslade 1989) to be an undescribed species of Acanthomurus Womersley, 1934. Isotoma chiltoni is also, therefore, now considered not to occur in Australia. Setocerura georgiana (Schäffer), recorded by Womersley (1934, 1939) as Isotoma georgiana Schäffer, was considered by Wise (1970) to be a misidentification for Isotoma, species inquirenda.
The species Pseudosorensia atlantica (Wise, 1970) identified by Greenslade (2006) from Macquarie Island is now recognised as Azoritoma macquariensisGreenslade & Potapov, 2008, which removes the genus Pseudosorensia from the Australian list. Similarly, Potapov et al. (2009) excluded the genus Subisotoma from the Australian fauna, removing two species, S. australis and S. loftyensis, to a new genus Isotopenola Potapov et. al. 2009 and returning C. tasmaniensis Womersley, 1942 to Cryptopygus Willem, 1901. Males of Isotopenola are sexually dimorphic and at some times of year develop spines dorsally (Greenslade & Potapov 2012).
Most isotomids live in soil and humus layers and the gross morphology of species is related to the position in the soil profile at which they live. There are a few wholly marine littoral genera, Archisotoma being one which can be extremely abundant interstitially below high tide mark on some low energy sandy beaches. In some severe habitats, such as are found in the Antarctic and arid zones, isotomids in the genus, Cryptopygus may be extremely abundant and may dominate the fauna.
Diagnosis
Characterised by: thorax I reduced and without chaetae, mandibular plate present, post-antennal organ present and rarely absent, abdominal segments either, V and VI and sometimes IV fused on not, abdomen IV never much longer than abdomen III, scales always absent, dens present or absent, sometimes reaching to abdomen segment IV, mucro present or absent, bothriotricha present or absent.
Genera are distinguished mainly on the degree of fusion of the posterior abdominal segments, structure and form of furca, chaetotaxy particularly that of certain sensory (s) setae, presence and form of spines, postantennal organ and development of ocelli.
Diagnosis References
Babenko, A. & Minor, M. 2015. Austrodontella monticola sp. nov., a new species of Collembola from montane New Zealand. Zootaxa 3974(1): 122–128
General References
Babenko, A. & Minor, M. 2015. Austrodontella monticola sp. nov., a new species of Collembola from montane New Zealand. Zootaxa 3974(1): 122–128
Carpenter, G.H. 1925. XI Some Collembola from Southern New Zealand. Memoirs of the Manchester Literary and Philosophical Society 69: 87-102
Deharveng, L. 1977. Étude chaetotaxique des Collemboles Isotomidae: premiers résultats. Bulletin du Muséum National d'Histoire Naturelle, Paris [published 1907-1971] Zool. 318: 597-619
Greenslade, P. 1989. Genera of Isotomidae with spined dentes from southern regions. pp. 107-118 in Dallai, R. (ed.). Third International Seminar on Apterygota. Siena, Italy, August 21-26, 1989. University of Siena.
Greenslade, P. & Potapov, M. 2008. A new genus and species of Isotominae (Collembola: Isotomidae) from cushion plants on sub-Antarctic Macquarie Island. Kanunnah 2: 87-97
Potapov, A., Babenko, A., Fjellberg, A. & Greenslade, P. 2009. Taxonomy of the Proisotoma complex. II. A revisions of the genus Subisotoma and a description of Isotopenola gen. nov. (Collembola: Isotomidae). Zootaxa 2314: 1-40
Potapov, M. 2001. Synopses on Palaearctic Collembola. Volume 3. Isotomidae. Abhandlungen und Berichte des Naturkundemuseums Görlitz 73(2): 1-603
Potapov, M., Babenko, A. & Fjellberg, A. 2006. Taxonomy of the Proisotoma complex. Redefinition of genera and description of new species of Scutisotoma and Weberacantha (Collembola, Isotomidae). Zootaxa 132: 1-74
Wise, K.A.J. 1970. Collembola of South Georgia. Pacific Insects Monographs 23: 183-208
Womersley, H. 1934. A preliminary account of the Collembola-Arthropleona of Australia. Part II Superfamily Entomobryoidea. Transactions of the Royal Society of South Australia 58: 86-138
History of changes
| Published | As part of group | Action Date | Action Type | Compiler(s) |
|---|---|---|---|---|
| 28-Jun-2018 | COLLEMBOLA Lubbock, 1870 | 19-Apr-2018 | MODIFIED | Dr Alice Wells |
| 18-May-2016 | ISOTOMIDAE | 17-May-2016 | MODIFIED | |
| 08-Jul-2015 | ISOTOMIDAE | 04-May-2016 | MODIFIED | |
| 28-Feb-2013 | 28-Feb-2013 | MODIFIED | ||
| 12-Feb-2010 | (import) |