300 



ECONOMIC ENTOMOLOGY 



BUPRESTID^ (METALLIC WOOD BORERS) 



Common Genera (after Blatchley) : 



A. Hind coxal plates dilated near base. 



B. Prosternal spine obtusely angulated behind the coxae; epimera of 

 metathorax triangular, uncovered. 

 C. Mentum entirely horn-like, elytra without yellow markings. — ■ 

 Dicer ca. 

 CC. Mentum membranous in front; elytra usually marked yellow. — 

 Buprestis. 

 BB. Prosternal spine acutely angulated behind the coxae; epimera of 

 metathorax partly covered by abdomen. Clypeus contracted, scutel- 

 lum large, first joint of hind tarsi elongate. — Chrysobothris. 

 AA. Hind coxal plates scarcely dilated near base. 



B. Hind tarsi with first joint as long as the three following; antennas 

 free; thorax truncate at base; clypeus not narrowed. — Agriliis. 



Flat-headed Apple-tree Borer {Chrysobothris femoraia Fab.). — (Con- 

 sult Bull. 437, U. S. Dep. Agric.) 



This borer attacks shade 

 and forest trees as well as 

 orchard trees, and is of common 

 occurrence. It attacks un- 

 healthy trees by preference 

 (Fig. 197). 



Adult. — A dark flattened 

 metallic brown buprestid beetle, 

 1^ inch long; wing-covers par- 

 allel, thin, tapering to a point 

 behind, under surface greenish- 

 blue; under surface of body 

 coppery-bronze. June. 

 Eggs. — Yellowish, ribbed, }^q inch long; deposited in crevices of 

 the bark, often several together. 



Larva. — ^Light yellow, i inch long when full grown; thorax broad 

 and flattened; abdomen flattened and often curved. Head small and 

 concealed by thorax; tunnels formed immediately under the bark, 

 sometimes girdling the trees. Matures in a year and winters as a full 

 grown larva. 



Pupa. — Yellowish; duration about 3 weeks, in spring. 

 Parasites. — Certain braconids, ichneumonids and chalcids. 



Fig. 197. — Plat-headed apple-tree borer 

 (Chrysobothris femorata): a, larva; b, beetle; 

 d, pupa. (After Chittenden, U. S. Bur. Ent.) 



