58 



strongly sclerotized; extremely large; deltoid; occupies one-half of the proximal arch; 

 discontinuous with BR; posteriorly strongly extended proximad and posteriad as a broad 

 sclerite. br projection distinct from BSc as an long and slender extension; oriented antero- 

 ventrad. 



Second Basal Plate (Fig.92) 



MA-BMA Junction absent. - MP-BMP Junction: MP continuous with BMP along all 

 margins. - Crimp Patterns absent. - BMP-CuA Brace absent. - BMP-BCuA Brace partially 

 reduced; weakly distinct; moderately narrow; formed as a secondary tube-like convexity 

 from the posterior margin of 2BP; extends posteriad from 2BP postero-distal section; 

 oriented posteriad; equally broad along the entire length. Anterior section weakly reduced. 

 Posterior section continuous with BCuA; fused to the antero-distal angle of BCuA. 

 Terminus fused to the anterior section of BCuA, just mesad of the distal margin. 

 Medial Basivenalia broad and moderately long; rectangular. Anterior and posterior margins 

 straight. Distal margin extremely deeply concave; strongly elevated from the surrounding 

 membrane. BMA broadly scaphoid; short but broad; completely fused to BMP. Proximal 

 surface weakly convex. Medial and distal surfaces flat. Anterior margin deeply concave. 

 Proximal arch moderately long; planate and falcate; moderately broad; enlarged antero- 

 proximally. Distal arch weakly distinct; moderately broad; extremely short; convex. BMP 

 separated from BMA by a shallow concavity; brace fused to BMP. Proximal section 

 extremely narrow; almost absent; rectangular; very weakly separated from BMA; convex. 

 Distal section very weakly separated into anterior and posterior sections; indistinct from 

 MP; formed as a reversed C-shape; slender; strongly convex. Postero-distal section less 

 convex than the antero-distal section. 



Cubital Basivenalia broadly fused. Postero-proximal margin of BCuA fused with the 

 antero-proximal margin of BCuP Suture line present. BCuA moderately broad and short; 

 convex; oriented distad; strongly sclerotized. Anterior margin with a moderately broad, 

 but shallow, concavity. Distal margin extended posteriad as a moderately strong, broad 

 convexity. BCuP stout; weakly convex; oriented posteriad; weakly sclerotized especially 

 posteriorly. Distal embayment broad but moderately shallow. - Cubitus Anterior 

 continuous with BCuA. Junction marked by a shallow groove. 



Basalare (Fig. 93) 



Head - HP lobe long; discontinuous with neck; appears to arise from the anterior margin 

 of a greatly enlarged BScP lobe; curves posteriad. Apex rounded. Dorsal surface very 

 weakly elevated above the BScP lobe; not polished. BScP lobe claviform; broad and 

 extended distad and anteriad; projects posteriad and strongly distad from neck. Dorsal 

 surface ovoid; strongly convex; polished; elevated from neck. Ventral surface polished. - 

 Posterior Subcostal Basivenale deltoid; polished. 



Discussion 



Monophyly of the Ceratocanthidae is supported by the fact that all of the taxa in this 

 family share the following two apomorphic character states of the wing articulation: 



