Identification, Images, & Information
For Insects, Spiders & Their Kin
For the United States & Canada
Clickable Guide
Moths Butterflies Flies Caterpillars Flies Dragonflies Flies Mantids Cockroaches Bees and Wasps Walkingsticks Earwigs Ants Termites Hoppers and Kin Hoppers and Kin Beetles True Bugs Fleas Grasshoppers and Kin Ticks Spiders Scorpions Centipedes Millipedes

The Coleopterists Society supports BugGuide.

Upcoming Events

BugGuide is a National Moth Week Partner. How to add your National Moth Week 2021 photos. July 17-25.

Photos of insects and people from the Spring 2021 gathering in Louisiana, April 28-May 2

National Moth Week 2020 photos of insects and people.

Photos of insects and people from the 2019 BugGuide Gathering in Louisiana, July 25-27

Discussion, insects and people from the 2018 gathering in Virginia, July 27-29

Photos of insects and people from the 2015 gathering in Wisconsin, July 10-12

Photos of insects and people from the 2014 gathering in Virginia, June 4-7.

Photos of insects and people from the 2013 gathering in Arizona, July 25-28

Previous events

Tentative T. labrata - Trirhabda labrata

Tentative T. labrata - Trirhabda labrata
Various (Scott's Valley & Rio Del Mar), Santa Cruz County, California, USA
Size: BL ~7.5mm
The five specimens above are from Randy Morgan's synoptic insect collection at UCSC for Santa Cruz County. The companion posts below give alternate views of some of these specimens:

Although these were not previously identified to species, I'm tentatively placing them under T. labrata based on studying the specimens and the works of Blake, Wilcox, and Swigoňová & Kjer (cf. references on the species info page).

The gestalt of these specimens, and the fact that they were collected on Baccharis pilularis, narrows the species to either T. flavolimbata or T. labrata. Blake (see pg. 30) indicated that T. labrata has larger, more metallic pronotal spots than T. flavolimbata, and also sparser pubescence on the elytra (making it appear more brilliantly colored). That, together with a number of other subtle characters culled from Blake's key and descriptions, and from the character matrix on pg. 371 of Swigoňová & Kjer(1), lead me to tentatively place these under T. labrata. Blake's remark (again on pg. 30), about the uncertainly in assigning Mannerheim's type to T. flavolimbata vs. T. labrata, seems especially relevant when one tries to distinguish specimens with character states varying near the borderlines between the two taxa. (Although, when available, images of aedeagi can help clearly distinguish the two...see Blake's Figures 17 & 19 here, and this image.)

I hope to visit and study the collections at the California Academy of Sciences and the Essig Museum at some point soon to see if I can get a more definitive idea on the determination here. In the meantime, I'd much appreciate any helpful comments, corrections, or confirmations from those who have knowledge and experience with this group.

These five specimens may turn out to include both T. labrata and T. flavolimbata, though the darkish, polished-looking, pronotum of the specimen on the bottom right seems especially similar to the type of T. labrata (except that it's missing the wrong antenna! :-). But at this point, for various reasons, I believe it's best to place these under T. labrata.