Macaronesian Muscidae (Diptera). II. The genus Limnophora Robineau-Desvoidy with description of a new Canarian endemic species
Author
Michelsen, Verner
text
Zootaxa
2021
2021-04-08
4952
1
101
127
journal article
7374
10.11646/zootaxa.4952.1.6
364a2818-9890-4a57-91cd-d5dcf0f36c6f
1175-5326
4671806
5C640B7A-AA7A-435B-93C7-F9AC61A71A9B
Macaronesian
Limnophora
: Habitat
requirements and threats
Most species of Macaronesian
Limnophora
have aquatic larvae and most of them may be strongly dependent on habitats of streaming water for larval development. Own field observations in the western Canary Islands suggest that the following species are wholly dependent on the availability of unpolluted lotic waters for larval development:
L. beckeri
,
L. bipunctata
,
L. flavitarsis
,
L. nitidithorax
and
L. riparia
. Bodies of stagnant water such as open tanks for water storage may be accepted by some species, e.g.
L. obsignatula
and
L. paneliusi
. In La Gomera I found
L. quaterna
in large numbers in an old orchard where larval development probably took place in heaps of rotten fruit and vegetables. Habitat requirements are unknown for the Afrotropical and Oriental
L. exigua
found in the
Cape Verde
Islands.
As documented by
Malmqvist
et al.
(1995)
,
Nilsson
et al.
(1998)
,
Crosskey & Báez (2004)
and others, the many permanent natural streams that earlier characterized the western Canarian islands of Gran Canaria, Tenerife, La Gomera and La Palma have diminished radically, because most fresh water is now captured by damming high in the mountains and conveyed down in closed pipes in order to satisfy the needs of agriculture, urbanization and tourism. The magnitude of eradication of natural water courses in the islands is evident from
Lüderitz
et al.
(2016)
who stated that the number of permanent streams in Gran Canaria has decreased from
285 in
1933 to
20 in
1973, and they found only two(!) moderately intact streams in 2009. A similar detour in undisturbed streams may as well have taken place in Tenerife, La Gomera and La Palma. As a consequence the invertebrate limnofauna of the
Canary Islands
is highly endangered. In respect to
Limnophora
, several species may face local or global extinction in a foreseeable future, unless targeted precautions are taken to protect and restore what is left of the perennial streams.