Diphlebia nymphoides (Tillyard, 1912)

ARROWHEAD ROCKMASTER

Family Diphlebiidae

A young male Arrowhead Rockmaster at the Bielsdown River Dorrigo on December 17th 2013.

A male Arrowhead Rockmaster at the Boyd River Dalmorton on October 13th 2012.

Two male Arrowhead Rockmasters at the Boyd River Dalmorton October 13th 2012.

A friend sent a photo of an Arrowhead Rockmaster that he found near Dalmorten. So Dalmorten went up to the top of my places to visit list.
The Boyd River near Dalmorten proved to be a haven for this beautiful blue damselfly. There were at least 8 males gathered around a rock next to a very shallow rapid which was lined with underwater vegetation. There were even more specimens, male and female, scattered around on other nearby rocks.

A female Arrowhead Rockmaster at the Boyd River Dalmorton on October 13th 2012.

A female Arrowhead Rockmaster at the Boyd River Dalmorton on October 13th 2012.

Detail of the posterior segments of the female at right.

The female Diphlebia nymphoides is less visible in her brownish to greenish tones. I think that the pattern on her abdomen looks more like arrowheads than the pattern on the males.

A mating pair of Arrowhead Rockmaster.

Female Arrowhead Rockmasters laying eggs in the little rapid at the Boyd River Dalmorton on October 13th 2012 (This is a video frame but if you look carefully you can see 5 females egglaying and 2 males flying over head).

A female Arrowhead Rockmaster laying eggs at the Boyd River Dalmorton on October 13th 2012.

On closer inspection of the little rapid, at least 5 female Arrowhead Rockmasters could be seen busy laying eggs. Males intermittently flew overhead keeping an eye on the females. One male grabbed a female in mid-air and mated with her. They landed on a rock amongst other males but did not stay together for very long.