Possible sawfly laying eggs
November 4, 2009
I was encouraged by Eric Eaton (Kaufman Field Guide to Insects of North America) to forward my question and photo to you for help in identification. He indicates that the insect is not a cicada, but is most likely a sawfly of some type. Thank you in advance for any guidance you can give!

My original question to him:
On September 8, 2007 I noted this (and numerous other identical) insects all laying eggs in similar clusters on the underside of leaves on a small tree. The tree had somewhat leathery leaves… perhaps a ficus of some sort? The location was within 100 feet of the ocean on the west end of the Honduran island of Roatan. I initially thought the insect was a type of fly – but am now convinced it is a cicada of some type. It seems to be morphologically similar to the Emerald cicada, Zammara smaragdina, from Honduras – photo at this site:
http://nathistoc.bio.uci.edu/Honduras/Hemiptera/Zammara%20smaragdina.htm
Over the last two years, I have contacted a series of individuals looking for help with ID, to no avail. Can you help?
Karen
West End of Roatan Island, Honduras

Seagrape Sawfly lays eggs

Dear Karen,
First, let us say that your photograph is lovely, and the insect is an interesting specimen.  We are quite intrigued that Eric Eaton referred you to us since we constantly depend upon Eric to make corrections for us.  We do have several contributors who love the challenge of identifying exotic species that we post, and we hope Karl is reading.  Our first thought is that this might be a Free Living Hemipteran in the suborder Auchenorrhyncha, which includes the Cicadas.  Eric Eaton has pointed out in the past that there are many exotic families found in the tropics that are not represented in temperate areas.  If Eric believes this is a Sawfly, we do not want to disagree.  We would strongly recommend that you provide a comment to our posting so that if six months down the line, your insect gets identified, you will be notified.  We do not maintain a database of email addresses for our readership, and though we send emails directly at the time of posting, once time has elapsed, we would not be notifying the querant directly. We would also inquire if you have any images showing the head of the insect as that might help to narrow the field of suspects.

Thank you for your comments.  With the help of both Eric Eaton and Dave Smith (research entomologist retired from the Smithsonian), I now have the identification for this sawfly.  Here is Dave Smith’s comment:
Argidae:  A sawfly, Sericoceros mexicanus (Kirby). For a good article on this, see:
Ciesla, W. M. 2002. Observations on the life history and habits of a tropical sawfly, Sericoceros mexicanus (Kirby) (Hymenoptera: Argidae) on Roatan Island, Honduras. The Forestry Chronicle 78(4): 515-521.
The plant must be seagrape, Coccoloba uvifera. Females lay eggs in clusters on the leaf, and stand guard over the eggs until they die. Larvae feed on the leaf edges. Sericoceros mexicanus occurs from southern Mexico to Panama. Other species of the genus are found from Mexico to S. Amer. and in Puerto Rico.

Once we had a name, finding more images online was easy.