Longicorn Coleopter a of Tropical America. 121 



some of which latter the prosternum between the coxas is also 

 reduced, as in ^phecomorphaj to a narrow thread. Stenopte- 

 rus murinus of Klusj, Avhich I venture to associate with the 

 typical species, bridges over the difference between it and 

 Odontocera and Aci/phoderes. In both the narrowed part of 

 the subulate elytra is of extreme length and tenuity, ending in 

 a sharp point. The tliorax in Sph. murina is not so broad as 

 in 8ph. chalyhea^ but it is oi similar shape ; and the third anten- 

 nal joint is relatively not so long. 



1. Sp}iecoinorp>Jm chalyhea^ Newm. 



Sphecomorpha chalyhea, Newman, I. c. p. 396. 

 S. biplagiatus, Lacord. /. c. p. 472, note. 



Amazons; Surinam; ^'Brazil" {Neivm.). 



The species is deceptively similar to Synceca cyanea, F., 

 a common wasp in the countries where the Sphecomorpha is 

 found. 



2. Sphecomorpha murina, Klug. 

 Stetioptertis murinus, Klug, Eutom. Bras. Specim. alter, p. 55, t. xliv. f. 8. 

 Rio Janeiro. 



The abdomen is much attenuated at the base, and remark- 

 ably vespiform in both sexes. 



Genus ISTHMIADE. 



Thomson, System. Ceramb. p. IGG ; Lacord. Gen. vol. viii. p. 504. 



The elytra are subulate (narrower than in Acyphoderes) . 

 The antennae have all joints elongate and slender, strongly 

 serrate from the sixth joint. The thorax is narrow, strongly 

 polished, and tuberculate. All the species are mimics of 

 Ichneumon flies of the group Braconidffi. 



1. Isthmiade hraconides, Perty. 



Stenopterus hraconidcs, Perty, Del. An. Art. Bras. p. 94, t. 19. f. 3. 

 Isthmiade hcphcestionoides, Thorns. I, c. p. 166. 



South Brazil. 



2. Isthmiade rubra, n. sp. 



I. castanco-rufa, nitida, vertice nigra ; elytris disco pallide fuscis 



vitreis ; alis pallide fuscis, ante apiccm fascia fulva. Long. 7-8 



lin. d 2- 



Prov. Rio Janeiro et Parand, Brazil (coll. W. W. Saunders^ 

 Dr. Baden, and H. W. Bates). 



Very similar to /. hraconides (Perty), differing in its bright 

 glossy chestnut-red colour, and especially its pale brown 



