Ecological parameter: resistance forms according to Tachet

Parameter group: life & body related parameters

Explanation:
In particular unfavourable conditions, some invertebrate species can develop specific survival strategies. Diapausing/dormant eggs, but also gemmula (e.g. Porifera) or statoblasts (e.g. Bryozoa) are resistance forms summarised in the category "egg". Larvae or adults of several species of invertebrates can elaborate protective cocoons or housings against desiccation. Many species may diapause as larvae (e.g. various molluscs and arthropods) or adults (e.g. diapausing troglophile caddisflies). Five categories are defined.

Tachet, H., Bournaud, M., Richoux, P. & Usseglio-Polatera, P. (2010): Invertébrés d'eau douce - systématique, biologie, écologie. CNRS Editions, Paris, 600 p.

Additional information:
Note that several classifications of the Tachet database are on higher taxonomic level than on species level. To display them in the list please enable "include higher taxonomic units" in the "advanced search".

Abbreviations:

Category name:	Abbreviations:	Explanation:
eggs, gemmula, statoblasts	egg	resisting in the egg, gemmula or statoblast stage
cocoons	coc	resisting in cocoons
housings against desiccation	hou	resisting in housings
diapause or dormancy	did	resisting through diapause or dormancy
none	non	no resistance form

Assigned taxa for each higher systematic unit:

Taxagroup	Number of assigned taxa / total number of taxa - percentage
Bivalvia	3 / 77 - 3.8%
Bryozoa	6 / 19 - 31.5%
Coelenterata	2 / 13 - 15.3%
Coleoptera	52 / 2678 - 1.9%
Crustacea	11 / 270 - 4%
Diptera (excl. Chironomidae)	2 / 2404 - 0%
Ephemeroptera	16 / 353 - 4.5%
Gastropoda	15 / 241 - 6.2%
Heteroptera	10 / 124 - 8%
Hirudinea	10 / 68 - 14.7%
Kamptozoa	1 / 1 - 100%
Lepidoptera	4 / 19 - 21%
Nemertini	1 / 1 - 100%
Odonata	17 / 174 - 9.7%
Oligochaeta	16 / 240 - 6.6%
Planipennia	1 / 12 - 8.3%
Plecoptera	9 / 576 - 1.5%
Polychaeta	1 / 13 - 7.6%
Porifera	3 / 12 - 25%
Trichoptera	38 / 1439 - 2.6%
Turbellaria	4 / 61 - 6.5%