December-January survey of Odonata at REGUA turns up 160 species

Male <em>Navicordulia kiautai</em> (© Tom Kompier)
Male Navicordulia kiautai (© Tom Kompier)
Male <em>Phyllocycla viridipleuris</em> (© Tom Kompier)
Male Phyllocycla viridipleuris (© Tom Kompier)
Male <em>Leptagrion elongatum</em> (© Tom Kompier)
Male Leptagrion elongatum (© Tom Kompier)
Female <em>Coryphaeschna viriditas</em> (© Tom Kompier)
Female Coryphaeschna viriditas (© Tom Kompier)
Male <em>Minagrion waltheri</em> (© Tom Kompier)
Male Minagrion waltheri (© Tom Kompier)

After the very productive survey in September-October it seemed unlikely to top its result of 115 identified species, but just the first week of our December-January survey we already topped 130. Of all 173 species recorded during our research to date, a cool 160 were found during our recent three week research period. To put that number in perspective, this is well over the number of Odonate species recorded in the whole of Europe.

With the advent of summer, not just the temperatures were up. Dragonflies and damselflies were abundant and not only in the obvious places. Of course the wetlands around the lodge were very productive, but now the trails in the forests also yielded many species all the way up to 1000 masl and higher. It is on the forest trails that many of the endemic damselflies are found. Let’s take a look at some of the more spectacular finds.

After a brief glimpse of an emerald Corduliinae in April 2012 at the top of the Salinas trail at approximately 1050 masl, at last emeralds were relocated again. In hand the species was verified as Navicordulia kiautai. This is one of the rare Atlantic Rainforest emeralds and had been recorded only twice before and never in Rio de Janeiro State. On subsequent visits it was seen regularly patrolling at midday above a wide trail bordered on both sides by forest. Up to six individuals were seen on any given day. Maybe the flight period is restricted, as it is unlikely that it was overlooked on previous visits.

Unexpected as well was the pretty Phyllocycla species recorded in the amazingly productive forest fragment not far from the lodge at 30 masl. This patch of lowland forest is part of the reserve and a testimony to its wealth. To date 10 gomphids have been found here and at least four Phyllocycla species are present. This individual stood out because of its very distinctive and whitish patterning, quite unlike the other gomphids present. Eventually it could be identified as P. viridipleuris, a species of which the occurrence in southeastern Brazil is shrouded in mystery. Likely, it is rare.

There are many species of Leptagrion forest dwelling damsels in Rio de Janeiro State, but during the whole of 2012 during all surveys only once a female Leptagrion was seen that did not belong to the omnipresent Leptagrion macrurum. At long last Susan Loose, a volunteer working on Odonata, located an unknown Leptagrion species at the beginning of the Green Trail, which turned out to be L. elongatum. Not a day after it was photographed and identified, a female of the same species was found right next to the reserve office!

Another interesting and surprising find at the forest fragment was a Mangrove Darner Coryphaeschna viriditas. On a very hot day an older female was found hanging along the forest edge. Professor Carvalho commented on the rarity of this species in Rio de Janeiro State. Clearly any greenish larger Aeshnid deserves careful attention, as they are around!

The last species to mention, although not mentioning all the other gems encountered is really an insult to them for which I apologize, is a Minagrion. After the September-October survey we did a short special to introduce this fabulous genus. During December we saw both Minagrion ribeiroi, so that species definitely also flies during the austral summer, and a third species, beautiful orange and blue Minagrion waltheri. This was found in bogs on the plain at Salinas, where is keeps inside the grassy emergent vegetation. It is another fabulous representative of this exquisite genus. Now three of the known five species have been recorded at REGUA.

Who is to say what more is out there.