First Damselfly of the Year, 2016

We saw our first damselfly of the year, Rambur's Forktail, the same day we saw the first dragonfly.  It flew on by us, however – surprisingly quickly for such a small insect – never to be seen again.

It was immediately recognizable by its green thorax and blue-tipped abdomen.  There's another forktail that's similar, the Desert Forktail, but it has yellow on the sides of the abdomen that extends up onto the top of the abdomen.  In Rambur's Forktail the yellow on the abdomen terminates in a nice, clean straight line about halfway up.  We haven't seen a Desert Forktail at our backyard pond, so we were pretty sure we were seeing a Rambur's Forktail.

A week or so later we went to Wild Horse Pass, and there we saw several Rambur's Forktails that were perching for us.  Here's a view of a male Rambur's Forktail at Wild Horse Pass:



Notice the green on the head and thorax, the blue tip to the abdomen, and the lack of yellow on the top of the abdomen.

Here's another male seen later the same day:



Heteromorphic females (those that don't look like males) start off bright orange when young, but with age turn more brownish and greenish.  Here's an immature heteromorphic female seen the same day at Wild Horse Pass:



Notice the nice straight line between the light color on the bottom of the abdomen, and the black on top – similar to the line of demarcation in the male.  We saw the female interact with a male, but she fended it off and they went their separate ways without mating.

Rambur's Forktail

One of the first odonates we see each year is the Rambur's Forktail.  In terms of coloration, it is similar to the Western Forktail that is common in Washington – green thorax with a blue tip to the abdomen – but the ranges are quite different.  Notice that the abdomen is black above and yellow below, with a nice straight line demarcating the two colors.  Here's a look at a male Rambur's Forktail:

A male Rambur's Forktail at the Gilbert Water Ranch.  Notice the hamules under segment 2 of the abdomen.

The eyes are similar to those of the Pacific Forktail – black above and greenish-blue below.

Female Rambur's Forktail can look a lot like a male, in which case they are said to be andromorphic (male form).  An example is shown below:

An andromorphic female Rambur's Forktail at the Gilbert Water Ranch.

Notice the flat bottom to segment 2 (S2) of the abdomen.  Thus, this individual lacks hamules, which indicates clearly that it is a female.  In the photo of the male above, the hamules are seen prominently on the bottom of S2.

Females can also look different from the males, and in this case are referred to as heteromorphic (different form).  Here's an example:

Heteromorphic female Rambur's Forktail.

Notice the orange thorax with the black front stripe, and the lack of hamules under S2.  As this individual matures it will become more greenish-brown.

Death in the Afternoon: A Forktail Fatality

The Gilbert Water Ranch (GWR) continues to be a source of lively odonate activity, in addition to the usual bird sightings.  In fact, the species list has grown in the last couple days, with the addition of the Flame Skimmer, Western Pondhawk, and Mexican Amberwing.  The amberwing has been seen a couple times here at our home since March 10, but this was our first sighting of it at the Water Ranch.

Here's the latest odonate species list for the GWR:

Damselflies
Familiar Bluet
Rambur's Forktail

Dragonflies
Common Green Darner
Flame Skimmer
Roseate Skimmer
Mexican Amberwing
Western Pondhawk
Variegated Meadowhawk
Red Saddlebags
Wandering Glider
Spot-winged Glider

One sad note on our last visit – the first thing we observed on arriving was a male Rambur's Forktail being devoured by a jumping spider.  Here's a picture:

It was painful to watch, but an integral part of nature, nonetheless.