96 



extremely narrow; convex; angled antero-proximad. Embayment normal size. Distal arch 

 discontinuous with radial stem; moderately broad; convex; broadly curved proximad; 

 oriented postero-proximad. br strongly sclerotized; occupies about one-third of the 

 proximal arch; discontinuous with BR. br projection deltoid; slender; concave; distinct 

 from BScA. 



Second Basal Plate (Fig. 155) 



MA-BMA Junction absent. - MP-BMP Junction: MP broadly continuous with BMP; arises 

 from below the BMP-BCuA brace. - Crimp Patterns absent. - BMP-CuA Brace absent. 

 - BMP-BCuA Brace present but modified; discontinuous with BMP; entire and greatly 

 strengthened; extends posteriad; moderately enlarged; equally broad along the entire 

 length; convex; distinct from BMP. Terminus fused to the disto-medial section of BCuA. 

 Point of fusion continuous. 



Medial Basivenalia reduced proximally. BMA broadly scaphoid; completely fused to BMP. 

 Proximal surface convex. Medial and distal surfaces planate. Anterior margin weakly 

 concave. Proximal arch moderately long; planate and straight; oriented proximad; strongly 

 curved ventrad. Apex terminates below BR proximal arch apex. Distal arch indistinct; 

 fused to the proximal section of BMP. BMP junction with BMA discontinuous and very 

 broad; fused to brace; markedly convex; separated from both IBP and BCu by membrane. 

 Proximal section broadly deltoid; planate; slopes ventro-distad. Distal section 

 indistinguishable from BMP-BCuA brace; long; broad; rectangular; strongly convex. 

 Cubital Basivenalia broadly fused. Posterior margin of BCuA fused with the anterior 

 margin of BCuP. Suture line present. BCuA small; convex; very weakly oriented postero- 

 distad; lies posteriad of BMP; weakly sclerotized. Anterior margin with a broad shallow 

 concavity. Distal margin partially continuous with CuA. BCuP deltoid; small; convex; 

 oriented postero-distad; weakly sclerotized. Distal embayment absent. - Cubitus Anterior 

 partially fused to BCuA. Junction marked by a distinct suture. 



Basalare (Fig. 156) 



Head - HP lobe slender; continuous with neck. Apex narrowly truncate. Dorsal surface 

 elevated from neck; not polished. BScP lobe claviform; weakly projects posteriad from 

 neck. Dorsal surface ovoid; weakly convex; polished; depressed from neck; slopes 

 ventrad. Ventral surface polished. - Posterior Subcostal Basivenale deltoid; polished. 



Discussion 



Although Chasmatopterinae do not display any autapomorphic character states of the wing 

 articulation and wing base, they do share two apomorphic character states of the wing 

 articulation and wing base with Melolonthinae, Hopliinae, Oncerinae and Acoma. The 

 evidence indicates that neither subfamilial nor tribal status is warranted, and it should be 

 returned to Melolonthinae as Chnaunanthus (Browne 1993). 



Chasmatopterinae share 22 apomorphic character states of the wing articulation and wing 

 base with Orphninae, Melolonthinae, Rutelinae, Dynastinae, Cetoniinae, Oncerinae, 

 Acoma, Hopliinae, Trichiinae and Valginae (Browne 1993). 



