Freshwater-turtle
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Pacifastacus leniusculus
Signal Crayfish
The signal crayfish is a large North American freshwater crayfish introduced to Europe in the 1960s to replace declining native fisheries. It has become one of the most ecologically impactful invasive decapods in Europe, outcompeting native crayfish and serving as a carrier of crayfish plague (Aphanomyces astaci). The species establishes self-sustaining populations rapidly, with six age cohorts documented within a few years of introduction. It shows sex- and size-specific coloration patterns, with males displaying more saturated and brighter ventral claw surfaces than females, suggesting a role in intraspecific communication.
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importuna
Tripanurga importuna is a sarcophagid fly specialized in locating and developing in carrion buried in sand. The species has a documented facultative association with freshwater turtle nests, where females deposit larvae primarily during hatching periods. Larvae preferentially scavenge necrotic tissue and damaged eggs, but will opportunistically prey upon live embryos and hatchlings. The species is considered a habitat specialist but food opportunist, capable of developing on various buried carrion sources.