metallic wood-boring beetle
(Agrilus auroguttatus Schaeffer, 1905)

This species is Native to certain parts of the United States but may be invasive to others

States Counties Points List Species Info

Introduction

Goldspotted oak borer (GSOB) is believed to have been transported via firewood or other human activity into southern California, specifically San Diego County, from Arizona, where it is considered a native beetle (ArborJet 2009, Smith 2009). First detected in 2004, it has caused extensive damage to coast live oaks, canyon live oaks and California black oaks in and around the Cleveland National Forest. It was determined to be the cause of oak mortality dating back to 2002. More than 20,000 trees on 620,000 acres have been affected. As of 2011, this insect was not a regulated pest under the Animal Plant Health Inspection Service, but was being watched closely (Center for Invasive Species Research 2011).

Distribution

Goldspotted oak borer is a native insect found in Arizona. Its spread to California and its infestation of coast live oak, canyon live oak and California black oak has proved problematic and has resulted in extensive mortality of those species in San Diego County, California, USA (Smith 2009, Hespenheide et al. 2009).

Identification

Adult goldspotted oak borers are a dull green color with a dark metallic sheen and have 6 yellow/gold spots on the wings. They have a bullet shape, 3/8th inches (10mm) long and 1/16th inches (2mm) wide. The larvae are slender, white, and have no legs. The tip of abdomen has two spines that look like pinchers. Larvae are about 11/16th inches (18mm) long by 1/8th inches (3 mm) wide. Larvae emerge from the tree through small (1/8th inches (3mm)) D-shaped holes. Pupae look similar to adults in size and shape, but are white (Smith 2009).

Citation

Agrilus auroguttatus. Author: Anne Buckelew Cumming, USDA Forest Service.

Selected Images


Taxonomic Rank

Domain: Eukarya
Kingdom: Animalia
Phylum: Arthropoda
Subphylum: Hexapoda
Class: Insecta
Subclass: Pterygota
Infraclass: Neoptera
Order: Coleoptera Linnaeus, 1758
Suborder: Polyphaga
Infraorder: Elateriformia Crowson, 1960
Superfamily: Buprestoidea Leach, 1815
Family: Buprestidae Leach, 1815
Subfamily: Agrilinae Laporte, 1835
Tribe: Agrilini Laporte, 1835
Genus: Agrilus Curtis 1825
Agrilus auroguttatus Schaeffer, 1905