Our guest naturalist, Len Blumin, posts about a recent expedition to find and photograph dragonflies along Pine Flat Road, Healdsburg.

I recently heard about the Black Petaltail, an unusual dragonfly found by [fellow naturalist] Alan Wight in a restoration area along upper Pine Flat Road, above ACR's Modini Mayacamas Preserves. The species has a wide range in the Pacific Northwest, as far south as Sonoma, but is nowhere common. A cool weather forecast convinced me to give it a try.

Driving up Pine Flat I was distracted by the plethora of wildflowers in bloom. Along the roadside I slowed to talk to a couple that was peering into a wet roadside gully. They asked if I was interested dragonflies. I was! The pair was none other than Kathy and Dave Biggs—well-known teachers and lovers of odes—and they kindly offered to show me the area where Alan had spotted the Black Petalflies. As it turns out, Kathy Biggs had been looking unsuccessfully for this dragonfly for several years following mining remediation work that included efforts to restore habitat for this species.

We searched along a seasonal seep, fed by a culvert above. The moist sloping hillside was just the right habitat, and Kathy soon discovered two male Black Petaltails, one of which landed briefly on on Kathy's light colored pants. She explained that they are not wary of people, and tend to perch on any available light substrate. After finding a window through the foliage I managed a few shots. The black and yellow pattern is distinct for this species. This is the male, as females appear only briefly when searching for a mate. Gotta wonder if the males land on light colors to make themselves more visible.


Male Black Petaltail by Len Blumin

The Petaltail family, Petaluridae, has only 11 species worldwide, with only 2 in the U.S (Paluson). The other is the Gray Petaltail, whose range does not extend west past Texas. The shot below shows the wing pattern nicely, along with a different view of the "petal-tail."


Detail of the wing and 'petaltail' of a Male Black Petaltail by Len Blumin

Black-and-yellow proved to be the ode colors of the day as Kathy and Dave Biggs had found a female Grappletail (dragonfly) when I encountered them on Pine Flat Road. Tough to find a window in the foliage to scope her out, but I managed this shot. The 65mm objective for our scope allows close focus down to 7 feet!


Female Grappletail by Len Blumin

In May 2014 [fellow naturalist] Leslie Flint and I had a great dragonfly outing at Lake Lagunitas, and were treated to several male Grappletails sunning on rocks in the stream below the dam. Here's a cropped view to better illustrate the interesting pattern on the top of the thorax, which resembles an urn shape, which has a pale blue base and is bordered by black stripes on the sides:


Male Grappletail by Len Blumin

Grappletails have very slender abdomens (compare the diameter to that of the thorax), which increases in thickness toward the back end, especially in the male. As you might guess, the bulge at the end gives them the name "clubtail."  The names of the various clubtail genera are varied and creative, and include the Sandragons, Leaftails, Forceptails (Greater and Lesser), Pond Clubtails, Common Clubtails, Hanging Clubtails, Spinylegs, Dragonhunters, Ringtails, Snaketails, Least Clubtails, and of course the Grappletail. The last is not plural because there is only one species, Octogomphus specularis, the Grappletail. Some of these sobriquets would perhaps serve well for a street gang or a videogame!
Simplified taxonomy (from Paulson, Dragonflies and Damselflies of the West).
Family:  GomphidaeThe Clubtails (950+ species worldwide, 100 of them found in North America, and 53 in our western regions.)
Genus: OctogomphusMonotypic, i.e. only one species.
Species: Octogomphus specularis - The Grappletail



Program note: Discover the dragonflies of the Modini Mayacamas with Sandra Hunt-von Arb on Saturday July 21, 8:30am-1:30pm. Details are listed in the calendar >