Streamer-tailed Dragonfly (Zygonychidium gracile)
The Streamer-tailed Dragonfly was described in 1970; it appears to be restricted to the Bandama River in Cote d’Ivoire.
The species was last recorded in 1972 and might well be extinct now; however, it appears to have a rather short flight season and thus might have been gone unnoticed.
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edited: 05.01.2024
Saint Helena Darter (Sympetrum dilatatum)
This dragonfly species was endemic to the island of Saint Helena in the middle of the Atlantic Ocean, it was the largest member of its genus.
The island of Saint Helena has not much free-running freshwater, thus the habitat for the dragonfly has always been very limited.
The dragonfly’s habitat was apparently completely destroyed due to the introduction of New Zealand Flax (Phormium tenax J. R. Forst. & G. Forst.) to the island. The plant was introduced sometimes in the 1850s to establish a flax industry, which was especially prospering from the beginning of the 20th century to 1966, when the last flax mill was finally closed. The New Zealand Flax, however, proved to be highly invasive and is still covering tremendous areas of Saint Helena’s mountains today.
The Saint Helena Darter was last recorded in 1963 and is now considered extinct.
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syn. Diplax dilatata Calvert
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edited: 29.05.2021
Lake Hula Phantom Flutterer (Rhyothemis semihyalina ssp. syriaca)
The Phantom Flutterer (Rhyothemis semihyalina (Desjardins)) is very widely distributed on the African continent. The species is sometimes split into several subspecies of which some may be valid and others not.
The form that formerly inhabited the Hula Valley in Israel was described as a distinct subspecies in 1850, it is thought of as having been a Pleistocene relict form. This alleged subspecies is said to differ from the nominate in having the black spots on the hindwings more reduced, leaving a narrow hyaline fringe along the posterior border of the wings. Structurally, however, both subspecies are identical. [1]
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The complete drainage of Lake Hula as well as of the swamps associated with this lake in 1958 led to the extinction not just only of this endemic dragonfly form.
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References:
[1] H. J. Dumont: Endemic dragonflies of Late Pleistocene age of the Hula Lake area (northern Israel), with notes on the Calopterygidae of the rivers Jordan (Israel, Jordan) and Litani (The Lebanon), and description of Urothemis edwardsi hulae subspec. nov. (Libellulidae). Odonatologica 4(1):1-9. 1975
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edited: 12.01.2019
Lake Hula Basker (Urothemis edwardsi ssp. hulae)
The Blue Basker (Urothemis edwardsi (Selys)) is very widespread on the African continent and once also inhabited parts of the Middle East. The Middle East form, however, is not universally accepted as a distinct taxon.
The Lake Hula Basker was described in 1975, it is thought to have been a Pleistocene relict that was restricted to the Hula Valley in Israel. It differs from the nominate in the extent of the basal spot on its hindwings which is greatly reduced.
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The Lake Hula Basker disappeared due to the complete drainage of Lake Hula and its attached swamps in 1958.
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The photo below shows the nominate race of that species.
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References:
[1] H. J. Dumont: Endemic dragonflies of Late Pleistocene age of the Hula Lake area (northern Israel), with notes on the Calopterygidae of the rivers Jordan (Israel, Jordan) and Litani (The Lebanon), and description of Urothemis edwardsi hulae subspec. nov. (Libellulidae). Odonatologica 4(1): 1-9. 1975
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edited: 12.01.2019