A Hidden Gem in My Vials of Moldy Old Leaves

Last year Erik van Nieukerken and Camiel Doorenweerd put out a request for specimens of leaf-mining moths in the family Gracillariidae, for Camiel’s PhD project entitled “Evolution and diversification of leafmining Lepidoptera and northern hardwood forest trees.” They are doing DNA work to prepare phylogenies (evolutionary “family trees”) of these tiny moths, as well as the even tinier Nepticulidae. I collected a number of samples for them at work and around my yard, and with their permission I threw in a few other miscellaneous dead things that I had failed to raise and was hoping could be identified with DNA.

One of the items I sent off to the Netherlands was a shriveled leaf that I’d kept for two years. It was a leaf mine in a thornless currant (maybe wax currant, Ribes cereum) that Julia and I had collected in Oregon in mid-October 2012.

When we collected the mines, I wasn’t entirely sure whether they were moth or sawfly larvae. But after finishing my keys to leaf mines of the plant order Saxifragales last year, I was sure that this wasn’t any of the species that are known to mine currant and gooseberry leaves, which include one heliozelid moth and several gracillariids. Another example:

The larvae never emerged from the mines to pupate, but I stubbornly refused to throw the leaves away, in the hope that somehow someone would be able to identify their remains. When Camiel opened up the leaf I sent, the larva was furry with mold:

Amazingly, Erik wrote to me today to tell me they had managed to sequence the DNA, and it was a 97% match for Acanthopteroctetes bimaculata (Acanthopteroctetidae). The family Acanthopteroctetidae is closely related to Eriocraniidae, and almost nothing is known about its few species (somehow the unpronounceable name seems fitting for such an obscure group of insects). Acanthopteroctetes unifascia is a leafminer on Ceanothus in California, and it is the only species that has been reared. Acanthopteroctetes bimaculata is known from Oregon and California, A. aurulenta from Oregon and Utah, and A. tripunctata from Montana. All four of these species have had their DNA barcoded, and 97% isn’t quite good enough to call this currant-mining moth A. bimaculata, but that is apparently the most closely related species that has a name. A fifth, undescribed species is known from a single California specimen. That’s it for the known North American representatives of this family, but there is another Acanthopteroctetes species in South Africa and a single species of another genus, Catapterix, in Crimea. Three other undescribed acanthopteroctetids are known from Peru, South Africa, and the Thienshan region (see references below).

I don’t know when I’ll next get out to Oregon, but if anyone out there is so inclined, it sure would be nice if someone would keep an eye out for these larvae and try to raise them. I’m including some photos of the host plant below, in case anyone is good with Oregon Ribes species and can confirm its identity.

References:

Davis, D. R. 1978. A revision of the North American moths of the superfamily Eriocranioidea with the proposal of a new family, Acanthopteroctetidae (Lepidoptera). Smithsonian Contributions to Zoology 251:1–131. (PDF)

Davis, D. R. 1984. A new Acanthopteroctetes from the Northwestern United States (Acanthopteroctetidae). J Lepid Soc 38:47–50. (PDF)

Kristensen, N. P., J. Rota, and S. Fischer. 2014. Notable Plesiomorphies and Notable Specializations: Head Structure of the Primitive “Tongue Moth” Acanthopteroctetes unifascia (Lepidoptera: Acanthopteroctetidae). Journal of Morphology 275:153–172. (PDF)