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Excerpts from Jim Conrad's
Naturalist Newsletter
from the July 20, 2018 Newsletter issued from Rancho Regenesis in the woods ±4kms west of Ek Balam Ruins; elevation ~40m (~130 ft), N~20.876°, W~88.170°; central Yucatán, MÉXICO
THORNBUSH DASHER DRAGONFLIES
The central Yucatan isn't a good place to see a variety of dragonflies because in our limestone-based karst topography there's little standing water, except in sinkhole bottoms and artificial ponds. The rancho's little concrete-lined pond is one of the latter, and one of the three dragonfly species I've seen there is shown below on a Tridax procumbens flower head bent over the water at the pond's edge:
That's the Thornbush Dasher, MICRATHYRIA HAGENII, distributed from the southern US not far from the Mexican border south through Mexico to Panama. The OdonataCentral.org webpage for the species describes it as the most widespread tropical dasher extending into the US, and describes its habitat as heavily vegetated ponds and lakes.
Our little cement pond has no plants in it other than a perpetual algal bloom, though the arid scrub around it is somewhat thick in places, with plenty of thorny bushes. Thornbush Dashers are often recognizable because they raise their white-spotted abdomens almost vertically over their brilliant, iridescent eyes.
This species' common name, Thornbush Dasher, actually is a generic name for about 48 species belonging to the genus Micrathyria. The name serves its purpose in the US where other thornbush dashers are unknown or little known, but down here it's inadequate, though no other English name seems to be available..
This week the pond's Thornbush Dashers have been mating, as shown below:
I read that females release their eggs, or "oviposit,"as they hover low over water, extruding egg masses about 2mm (1/16th inch) in diameter, flicking their abdomens upwards to release them. They also oviposit on available floating vegetation.
During summers the Thornbush Dasher wanders northward into the US sometimes as far as Arkansas. As global warming takes place it's a species that could turn up where it's never been sighted before.
from the August 23, 2018 Newsletter issued from Rancho Regenesis in the woods ±4kms west of Ek Balam Ruins; elevation ~40m (~130 ft), N~20.876°, W~88.170°; central Yucatán, MÉXICO
MID-AIR MATING THORNBUSH DASHERS
This week I happened to have the camera pointed just where a mating couple chose to hoover, and the camera focused on them instead of the background as it usually does, so now you can see the nifty shot below:
