Gray-drake
Guides
Siphlonurus
primitive minnow mayflies, gray drakes
Siphlonurus is a genus of primitive minnow mayflies in the family Siphlonuridae, comprising more than 40 described species. Species inhabit temporary and intermittent ponds, with nymphal development occurring during spring months and adult emergence in late May to June. Adults are non-feeding and rely on energy reserves accumulated during the aquatic larval stage. The genus is notable among fly fishers for species such as Siphlonurus quebecensis (early brown quill), which is imitated with specialized fly patterns.
Siphlonurus alternatus
Northern Summer Mayfly
Siphlonurus alternatus is a primitive minnow mayfly with a Holarctic distribution spanning North America and Europe. The species is univoltine, overwintering as eggs and emerging as adults between May and August. Larvae inhabit deep pools in rivers, streams, and calcareous lakes, where they feed on fine particulate organic detritus. Adults emerge during daylight hours, with males forming swarms at dawn and dusk.
Siphlonurus columbianus
Columbian gray drake
Siphlonurus columbianus is a species of mayfly in the family Siphlonuridae, described by James Halliday McDunnough in 1925. It is native to the Nearctic region and is one of several Siphlonurus species known to fly fishermen as "gray drakes." Adults are medium-sized mayflies with distinctive body segmentation. Like other members of its genus, it has a two-winged adult stage and an aquatic nymphal stage. The species is occasionally referenced in angling literature, though detailed biological studies appear limited.
Siphlonurus quebecensis
early brown quill mayfly, gray drake
Siphlonurus quebecensis is a species of primitive minnow mayfly in the family Siphlonuridae. It occurs in North America and is known to anglers as the 'early brown quill' or 'gray drake,' a name reflected in fly-fishing patterns designed to imitate its adult form. The species is part of a group of mayflies whose aquatic nymphs and winged adults serve as important prey for trout and other sport fish.
Siphlonurus rapidus
Siphlonurus rapidus is a species of primitive minnow mayfly in the family Siphlonuridae. It was described by McDunnough in 1924. The species is found in North America. Like other members of the genus Siphlonurus, it is considered a "gray drake" mayfly of interest to fly fishermen.