Toad gold fly

from Wikipedia, the free encyclopedia
Toad gold fly
Lucilia.bufonivora .-. Lindsey.jpg

Toad gold fly ( Lucilia bufonivora )

Systematics
Class : Insects (Insecta)
Order : Fly (Diptera)
Subordination : Flies (Brachycera)
Family : Blowflies (Calliphoridae)
Genre : Gold Flies ( Lucilia )
Type : Toad gold fly
Scientific name
Lucilia bufonivora
Moniez , 1876

The toad gold fly ( Lucilia bufonivora ), also known as the toad fly , is a species of the blowfly family (Calliphoridae) that also occurs in Central Europe . Several species of the genus Lucilia are optional (optional) or obligatory (exclusive) parasitoids of amphibians . The larvae of the golden toad fly belong to the latter group. They eat the inner tissue, especially in the head area of ​​living toads or other amphibians, until they die and the maggots finally pupate in the ground. This infestation of living vertebrate tissue with fly maggots is known as myiasis (fly maggot disease), regardless of the host species .

features

The imagoes of Lucilia bufonivora resemble some other gold species of fly, such as the more common Emperor Gold fly ( Lucilia Caesar ). They reach a body length of up to nine millimeters and have a green-gold metallic shiny body. The fourth longitudinal artery of the wing is particularly sharply bent in this species.

Way of life

Specimen of a Mediterranean common toad from Italy with fly eggs on its back. Presumably they are from Lucilia bufonivora
Adult common toad with fly eggs, larvae in the nostril, Kottenforst near Bonn, 2020
Common toad with a golden fly sitting on it, eggs and larvae in the nostril
Common toad parasitized by larvae of the toad gold fly. The infestation is still at an early stage, but the toad's nostrils are already widened by the larvae
Slightly more advanced head deformation in an infested common toad
Common toad with maggots of the gold fly

Goldflies live mainly in flowering herbaceous perennials, especially on umbellifers , and feed on pollen and nectar there . For reproduction, the animals place their white, elongated eggs on the back or head of toads and other amphibians in the summer months. The common toad is particularly affected ; Moreover, but also are natterjack toad , toad , frog , midwife toad , spadefoot , tree frog , moor frog , green frog and for once the fire salamander has a host species. The quickly hatching larvae enter the host's head through the nostrils, where they eat their way through the soft tissue of the living animal. After a few days, the front muzzle and head area can be completely deformed and disfigured. When the larvae have reached the brain or other vital organs or body functions have been destroyed, the amphibian eventually dies. In their last larval stage, the maggots sometimes ate the carcass almost completely - including the skin and connective tissue, and possibly even cartilage and bones . Then they bury themselves in the moist soil and pupate .

The entire process, from hatching of the fly maggots from the eggs to penetration into the host, the larval development in its body, its perishing and until the larvae pupate takes about three to four weeks. A dead toad can be completely skeletonized within one to two weeks (depending on the infestation density). It should be taken into account that there is often a secondary infestation of the carcass with larvae of other fly species. The pupal stage until the next generation of finished gold flies hatch takes about one to three weeks.

Effects on amphibian populations

Many individual observations, but only a few systematic studies, are available on the infestation of amphibians with Lucilia larvae from Central Europe, among others. Whether the diseased amphibians were primarily infected with Lucilia bufonivora is also still questionable, as some other fly species are at least facultative amphibian parasitoids. The effects on amphibian populations cannot be conclusively assessed. Under conditions that are favorable for the goldflies, larger parts of a toad population, apparently especially larger, especially female animals, are killed by maggots in their summer habitat. In this respect, myiasis can definitely be a significant cause of mortality at the population level. In fact, however, various factors seem to prevent a serious general impact on amphibian populations. This includes, among other things, the active shedding of eggs or larvae by the toad, for example when moulting. However, premature host death, the animals' stay in the water or climatic factors can also influence the local infestation rate.

For the infested but defenseless frogs it is certainly a torturous event for days. But even this, there are trivializing votes: Compared to anthropogenic hazard causes of amphibian populations, such as habitat destruction and road, losses play through Lucilia - myiasis nationally probably no bestandslimitierende role. Rather, it is a matter of natural processes whose ecological significance has not yet been adequately understood. Therefore, an objective, neutral view is appropriate, even if the fate of the individual infested amphibian may appear cruel.

Sources and further information

Individual evidence

  1. ^ F. Zumpt: Myiasis in man and animals in the old world: a textbook for physicians, veterinarians and zoologists - London, 1965, (Butterworths)
  2. ^ V. Neumann & F. Meyer: Lucilia bufonivora MONIEZ, 1876 - a euryxen amphibian parasite. In: Communications from the Zoological Museum Berlin 70 (1994): 331–341.
  3. ↑ Vít Zavadil: On the parasitism of the toad gold fly (Lucilia bufonivora MONIEZ, 1876) on common toads (Bufo bufo) - defense behavior and limiting factors. In: Zeitschrift für Feldherpetologie 4 (1997): 1-12.
  4. ↑ a b Klaus Weddeling & Thomas Kordges: Lucilia bufonivora infestation (myiasis) in amphibians in North Rhine-Westphalia - distribution, host species, ecology and phenology. In: Zeitschrift für Feldherpetologie 15 (2008): 183–202. ( PDF full text online)
  5. ^ Henk Strijbosch: Mortality in a population of Bufo bufo resulting from the fly Lucilia bufonivora. In: Oecologia 45 (1980): 285-286.
  6. ↑ Klaus Weddeling: Of flies and common toads: Myiasis in Anuren in the Drachenfelser Ländchen near Bonn - fly species, phenology, hatching success and density effects in amphibian carcasses. In: Zeitschrift für Feldherpetologie 21 (2014): 165-182.

literature

  • Thomas Kordges: Strong infestation of the common toad (Bufo bufo) by the toad gold fly (Lucilia bufonivora MONIEZ, 1876) . In: Zeitschrift für Feldherpetologie 7 (2000): 211-218. Laurenti-Verlag, Bochum / Bielefeld. ISSN  0946-7998
  • Henk Strijbosch: Mortality in a population of Bufo bufo resulting from the fly Lucilia bufonivora. In: Oecologia 45 (1980): 285-286.
  • Klaus Weddeling: About flies and common toads: Myiasis in Anuren in the Drachenfelser Ländchen near Bonn - fly species, phenology, hatching success and density effects in amphibian carcasses. In: Zeitschrift für Feldherpetologie 21 (2014): 165-182. ISSN  0946-7998 ( PDF full text online)
  • Klaus Weddeling, Thomas Kordges & Martin Schlüpmann: New evidence of fly maggot disease (myiasis) in Anuren in North Rhine-Westphalia. - Zeitschrift für Feldherpetologie 24 (2017): 113-118. ( Summary )
  • Vít Zavadil: On the parasitism of the toad gold fly (Lucilia bufonivora MONIEZ, 1876) on common toads (Bufo bufo) - defense behavior and limiting factors. In: Zeitschrift für Feldherpetologie 4 (1997): 1-12. Laurenti-Verlag, Bochum / Bielefeld. ISSN  0946-7998

Web links

Commons : Toad gold fly ( Lucilia bufonivora )  - Collection of images, videos and audio files