I was going through photographs from my visit to Brazil this past January and came across this forgotten photo of a longhorned beetle taken near Campinas in São Paulo. Although I didn’t recognize the genus immediately, I was rather sure it belonged to the great tribe Trachyderini, generally characterized by medium to large-sized, brightly colored, diurnal (active during the day) species. Knowing this it didn’t take me long to identify the species as Oxymerus aculeatus, occurring from Nicaragua and the West Indies south to Bolivia and Uruguay and, thus, the most widely distributed of the ten species in this exclusively Neotropical genus. As is typical with such widespread species, a few subspecies have also been described—this one should be the nominate subspecies, widely distributed throughout central, eastern, and southeastern Brazil (Hingrid et al 2010).
Like most other members of the family Cerambycidae, O. aculeatus is presumed to utilize dead or dying wood for larval development, but little else is known regarding its habits and host plants. Members of the tribe are often found frequenting flowers, although this and a few other individuals were encountered resting on the underside of foliage on an unidentified tree. The Florida Department of Agriculture & Consumer Services has become concerned about the possible establishment of this species in the U.S. after two recent collections of the West Indian subspecies in south Florida (Thomas 2006). Whether it goes on to have any economic impact remains to be seen, but if recent history with other wood boring beetles is any indication (e.g., Asian longhorned beetle, Anoplophora glabripennis; emerald ash borer, Agrilus planipennis; etc.) the concern may be warranted.
Hingrid Y. S. Q., J. P. Botero R. and M. L. Monné. 2010. Insecta, Coleoptera, Cerambycidae, Cerambycinae, Trachyderini: New state and country records from South America. Checklist 6(3):364–376.
Thomas, M. C. 2006. Another Neotropical longhorn beetle (Coleoptera: Cerambycidae) apparently new to the mainland of Florida. UF/IFAS Pest Alert (website accessed 7 Nov 2011).
Copyright © Ted C. MacRae 2011
7 thoughts on “A Brazilian longhorned beetle – Oxymerus aculeatus”
Nice! Do you have a shot that shows the entire length of the antennae? Love long-horned beetles. SO frequently stylish and arresting. =)
Nope, but they were quite long on this presumed male individual. In general I’ve been disappointed with my attempts to photograph longhorned beetles with the whole of their antennae in the photo – the beetle itself just looks too small in the photo. I probably need to do a better job of composing an interesting background in such photos.
I have the same problem with katydids, or worse. The body ends up off to one side, and the antennae are so fine that one can’t have a too interesting background, or they disappear. At least with katydids, one might with patience get them pulling an antenna through the mouthparts to clean it. B.t.w., how do ceramycids clean their antennae?
Same way – pulling them through the mouthparts, although I can’t say I’ve seen them doing it near as often as one sees katydids doing it.
as long as these feed in dead or dying wood, they may be less of a threat than phloem feeders. I am wondering how these long antenna beetles emerge from their larval stage when the antenna don’t go along their bodies but jut out in front?
More than likely they are dead wood feeders, but until we know for sure they aren’t phloem feeders there will be concern.
Longhomed beetle pupae develop with their antennae wrapped in curls along each side of the body. When they molt to the adult the antennal segments straighten and harden but still lay back and wrap around the pupal cell. Only after the adult chews its way out of the wood are the antennae held forward for the first time.
I’m interested in learning about them, and I thought that your blog would be a great introduction.