XORTH AMERICAN BOSTRICHIDAE / 



Melalcus exesus (LeConte) 



Exops exesus LeConte, 1858, Acad. Nat. Sci. Phila. X : 74. 



Polyeaon exesus Horn. 1878, Amer. Phil. Soc. Proc. 17: 552. 553; Gorham, 1883, 



Biol. Centr.-Arner., Coleopt., v. 3, pt. 2, pp. 210-211, pi. 10, figs. 18-19. 

 Heterarthron exesus Lesne, 1906, Soc. Ent. de France Ann. 75: 394, 396; 1935, 



Paris Mns. d'Hist. Nat. Arch. (ser. 6) 12: 429, fig. 7 (Tricent. vol.); 1938, 



in Junk (pub.), Coleopt. Cat., pt. 161, p. 28; 1939, Rev. Frangaise Ent. 6: 



95-97 : Belkin, 1940, Ent. News 51 :193. 

 Heterarthron femoralis Lesne (not Fabricius), 1896, Soc. Ent. de France Ann. 



65 : 15, 18-19, figs. 5, 6. pi. 8, fig. 2. pi. 9, figs. 17-19 (part). 



The writer has not examined any specimens of this species, and it 

 is placed in the key entirely upon the characters given in the original 

 description and by other writers. The following is a copy of LeConte's 

 original description : 



Exops exesus, ater, capite confertissinie granulato, thorace latitudine hand 

 breviore convexo. postice pa rum angustato, lateribus rectis. angulis omnibus 

 rotundatis. granulato-punctato. modice canaliculate, elytris thorace sesqui latiori- 

 bus cylindricis antice truncatis. fortiter cribratim postice confluenter punctatis 

 et sensim granulatis, postice oblique declivibus et linea elevata arcuata notatis, 

 antennis ferrugineis. Long. .47. 



RingcroM Barracks. Texas. Mr. Haldeman. The posterior curved elevated line 

 of the elytra becomes marginal near the apex, but anteriorly bends inwards so 

 as to define the oblique declivity. The curious species is in the transition from 

 Exops towards Apate and allied genera. 



Type. — In the LeConte Collection in the Museum of Comparative 

 Zoology. Cambridge. Mass. 



Distribution. — This specie- is distributed throughout southern 

 Texas, Lower California. Mexico, and Central America. Lesne 

 (1939) gives the distribution as follows : 



Texas : Ringgold Barracks on the Rio Grande. 



Mexico: Cocula. Zumpango, Oaxaca, Juchitan, Vera Cruz, Cordoba, Tehuantepec, 



Chiapas, and Tapachula. 

 Guatemala : Torola and San Geronimo. 

 Honduras : Amapala. 

 Nicaragua : Managua and Contales. 

 Costa Rica : Surubres, San Mateo, La Uruca, Turrialba, and San Jose. 



Hosts. — Xothing has been recorded on the host plants of this species. 



Melalgia plicatus (LeConte) 



Polyeaon plicatus LeConte, 1S74. Amer. Ent. Soc. Trans. 5: 65-66: Horn, 1878, 

 Amer. Phil. Soc. Proc. 17: 552, 553^554; Gorham, 1883, Biol. Centr.-Arner., 

 Coleopt, v. 3, pt. 2, p. 211. 



Heterarthron plicatus Lesne. 1896, Soc. Ent. de France Ann. 65: 115. 119-120 

 (part); 1937, Paris Mus. d"Hist. Nat. Bui. (ser. 2), 9: 5; 1938, in Junk 

 (pub.), Coleopt. Cat., pt. 101. p. 28; Anderson, 1939, Wash. Acad. Sri. Jour. 

 29: 388, fig. 18 (larvae). 



Polyeaon obliquus LeConte. 1*74. Amer. Ent. Soc. Trans. 5 : 66 ; Horn, 187S, Amer. 

 Phil. Soc. Proc. 17 : 552, 553. 



Male. — Elongate, cylindrical, uniformly reddish brown to brownish 

 black. 



Head in front subequal in width to pronotum at apex, strongly 

 convex posteriorly, vaguely flattened along anterior margin at middle, 

 densely, finely, uniformly granulose, rather densely clothed with 

 moderately long, semierect. yellowish hairs, with a few long, erect, 

 yellowish hairs intermixed: clypeus convex, broadly, vaguely emar- 

 ginate or truncate in front: labrum slightly flattened, broadly, arcu- 

 ately emarginate in front; eyes separated on the front (when viewed 



