Golden Drake
Anthopotamus distinctus
NYMPH 2
Size: 12- 16 mm
Body: Light amber to reddish brown with lighter markings
Legs: Light reddish brown with darker banding
Tails: Three tails
Gills: Forked, feathery and elongate; held out to sides
Nymph Look Alikes 2
Golden Drake nymphs are most easily confused with other tusked mayflies and
members of the Leptophlebiidae family. Nymphs of A. distinctus are easily distinguished from those of the other tusked mayflies (Ephemera and Hexagenia in Massachusetts) by the gills: held laterally and out away from the body on former, while held dorsally up over the body on the latter. The well-developed tusks of mature A. distinctus nymphs are absent from all eastern members of the Leptophlebiidae.
DUN (Subimago) 2
Size: 12 to 16 mm
Body: Pale yellow, with light rose/brown stripes on side of abdomen
Wings: Yellow with black cross veins
Tails: Three tails, light brown
Note: The combination of these characters allows separation of A. distinctus from the other three Anthopotamus species. A. myops lacks any markings on the abdomen, while A. neglectus and A. verticis are distinctly smaller species, ranging from 7 to 9 mm. Only a A. distinctus is presently known from New England, but all 3 other species occur in eastern New York.
SPINNER (Imago) 2
Size: 12 to 15 mm
Body: white abdomen and yellow thorax
Wings: Clear wings (hyaline)
Tails: Three tails, faintly banded
Dun/Spinner Look Alikes 2
Golden Drake duns are most likely to be confused with the duns of Hexagenia limbata and Ephemera varia. H. limbata occurs in lakes much more frequently than in moving waters in New England, and “Hex” duns are considerably larger, ranging from 17 to 40 mm. E. varia (the Yellow Drake) is a paler yellow and has light brown markings on the wings. The spinners of E. varia are primarily brown on the dorsal side of the abdomen, and the brown markings on the wings even more disintct. The larger, whitish Anthopotamus distinctus spinners with entirely hylaline wings are not readily confused with any other mayflies in the region on midsummer nights.
HABITAT & DISTRIBUTION 2
The genus Anthopotamus includes four species; only A. distinctus is currently known to occur in New England. Inhabitants of warmer reaches of medium-to-larger rivers, the Golden Drake is unique among the mayflies in that the nymphs exhibit behavior intermediate of crawling and burrowing mayflies. Rather than borrowing into soft sediments, they settle into the crevices and depressions among the detritus in slower moving sections of rivers.
Photo of A. distinctus habitat: http://riverscalendar.drupalgardens.com/media-gallery/detail/37/2091
LIFE CYCLE - EMERGENCE 2
The Golden Drake is a mid-summer hatch, typically occurring in July in Massachusetts. Nymphs are said to actively scurry about the river bottom prior to emergence. The large yellow duns emerge in the late afternoon and evening and may drift atop the water’s surface for some distance as they wait for their large wings to dry. Mating flights by spinners occur in the evenings, and spinners fall at dusk into darkness.
Massachusetts: Late June June through July, depending on weather and water
temperatures.
Degree of difficulty 3
This table is meant to help users get an idea of how easy/hard it is to ID this species to any taxonomic level, and to give an idea of the characters (or features) that are important to accurately identifying a specimen. As a general guideline, these degree of difficulty levels translate to the type of effort needed to reliably ID a specimen to that taxonomic level, as long as the associated features are confirmed. Of coarse there will/may be exceptions to these general rules.
Anthopotamus distinctus
Taxonmoic level
Taxonomic Name
Feature
Degree of difficulty
Order
Ephemeroptera
Wing Shape
1
Family
Potamanthidae
NA
3
Genus
Anthopotamus
Pale yellow/with darker blotches along sides
3
Species
distinctus
Pale yellow 12-16mm, markings on the abdomen, three tailslate June-July
3
Degree of Difficulty
Degree of Difficulty
Description
1
Can be ID’d on the wing or water.
2
A specimen in the hand can be ID’d.
3
Can be ID’d by studying a decent photo of the specimen.
4
Can be ID’d by studying a captured & preserved specimen, usually under some magnification.
5
Proper ID requires study of preserved specimen under magnification, usually looking for some feature that can be difficult to confirm. Usually requires training or confirmation from a professional.
Sources and Credits
- (c) Jerry Schoen, all rights reserved, uploaded by Jerry Schoen
- Adapted by Jay Aylward from a work by (c) Jerry Schoen, some rights reserved (CC BY-SA)
- (c) Jay Aylward, some rights reserved (CC BY-SA)
