Fundy Nature Notes, Quotes and Anecdotes ²

Northern Spreadwing, Leste disjoint(Lestes disjunctus)Adult size: 33-42 mm

Habitat/Status: A common inhabitant of a wide variety of ponds, especially highly vegetated ones, but also vernal ponds, lakes, bog pools and slow-moving streams throughout the Maritimes.

Typical flight period: In the Maritimes, flies from the end of June until mid-October (dates June 22nd NB – October 22nd NS).

ID hints: This dark, late-season species is likely the most common and widespread of its group in the region and indeed across North America. However, despite its apparent abundance, there is not quite as much information on this species as one would expect, as great care must be employed to differentiate it from the very similar Sweetflag Spreadwing (Lestes forcipatus) and Lyre-tipped Spreadwing (Lestes unguiculatus) in the field. Nevertheless, with experience, one generally can distinguish these three species through binoculars with good results, especially the Northern versus the Lyre-tipped. But, it is best to confirm the species ID by examining the individual in hand (or even under a microscope) to be absolutely certain of its identity. For the male Northern, the trick is that the teeth on the cerci (outer “arms” of the claspers) are proportionately closer together than in those of the Sweetflag Spreadwing; also, the distal teeth on the Northern’s cerci are as prominent as its own basal ones, as opposed to much smaller distal teeth in the case of Sweetflag (see discussion/images of the Sweetflag Spreadwing). Finally, the shape of the Lyre-tipped’s claspers is unique and unmistakeable in the hand, often even visible in good close-focus binoculars.

Nature Notes: - This species apparently likes quite densely vegetated ponds best, and it spends most of its time on the edge of such water bodies.

• The Northern Spreadwing is moderately tolerant of water having moderate to high conductivity (salt content), its resistance level falling in between that of the Emerald Spreadwing (least tolerant) and the Spotted Spreadwing (most tolerant).

Sources and Credits

1. (c) Denis Doucet, some rights reserved (CC BY-NC), uploaded by Denis Doucet
2. (c) Denis Doucet, some rights reserved (CC BY-NC)

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