Ischnura denticollis
photo (above) 7 Oct 2006 Salinas River at Salinas
Black-fronted Forktail is a very small and delicate forktail. It is a weak flyer and easily overlooked among low, emergent vegetation in shallow water. Yet, when found and viewed at close range, the male (above) is a gorgeous black-and-turquoise damselfly. 
We captured this particular male — the shot (below) shows it actual life-size: only 1 inch long. That should convince you just how tiny this ode is. 
Indeed, Manolis (2003) says that "this is the smallest damselfly found in most of California." But through a hand-lens — or, here, close-up photography (left) — many details can be observed.

 Note that the black-and-torquoise includes the eyes (top half black, lower half aqua) and legs.
Close-up notice the small blue spots adjacent to the eyes and the very extensively black upper surface to the thorax. This solid, iridescent pattern to the top of the thorax — without stripes or spots — is unlike any other California forktail . ... except one: San Francisco Forktail I. gemina. The latter is so similar in pattern that it can only be identified by the male's appendages. Black-fronted and San Francisco Forktails hybridize where the ranges meet. There is now evidence that Black-fronted Forktail has 'swamped out' the more specialized San Francisco Forktail in the southern part of the latter's former range. Specimens of San Francisco Forktail were collected on the Salinas River in 1946. It is now 50 years later and no I. gemina have been found in MTY for decades. They are also missing from their former range around the southern end of San Francisco Bay. Today, only Black-fronteds occur at these spots.

Adult female Black-fronted Forktail (not shown) are similar but not as bright. The rich turquoise color of the male is replaced by paler green or tan. Immature females are orangey-tan.
 all photos 7 Oct 2006 Salinas River at Salinas

Here (left) is an enlarged, close-up view of the male's appendages. The prominent black hook atop the 10th segment is not an appendage. Rather, the cerci are the final blackish thin disc at the end of the segment. Below that, note the paraproct: a pale (whitish) spur that extends the farthest to the right of any portion of the segment. Male I. gemina lack this projecting spine at the lower edge of the inferior appendage.
Viewed from above, Black-fronted Forktail is extensively black. Only the tiny eyespots and the extensive turquoise blotch across the 8th & 9th abdominal segments relieve the otherwise all-shiny-black upperparts. Given the tiny size of this insect, it almost 'disappears' into the wet sand.

Black-fronted Forktail is widespread in California. It frequents low sedges and beds of grass near springs, small ponds, and "still backwater lagoons of rivers" (Manolis 2003). Dennis Paulson once stopped along the Salinas River, 5 miles south of San Ardo, back on 1 Sep 1977. He collected a pair of Black-fronted Forktail, and wrote in his notes: "very abundant in marsh, few at the river." Indeed, we located the one shown in these photos on a little backwater side-branch of the Salinas River — well away from the strong currents in the main river. At the right date and in the right microhabitat, it can be a very common species.

Map Black-fronted ForktailThe map shows the currently known MTY locations of Black-fronted Forktail. Most are along either the Salinas or the Carmel rivers, although there are records from Laguna Grande in Seaside. It likely occurs at other locales which have the same shallow backwater habitat of low grass or sedges.

Flight dates in MTY range from 12 March to 7 October. Elsewhere in California the flight dates range from March to November (Manolis 2003).

Literature cited:
  • Manolis, T. 2003. Dragonflies and Damselflies of California. Univ. of Calif. Press, Berkeley.
Web resources:
Major identification web sites with much information on California odes include: For sites with excellent photos to compare for identification or to simply enjoy, see: Many of these sites have links to other useful pages. Kathy Biggs's site is particularly useful in her selection of links.

All photos © Don Roberson 2007


Page created 24 Feb 2007