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ON BRACONIDAE PARASITIC ON DIATRAEA SACCHARALIS IN 



DEMERARA. 



By R. E. Turner. 



Three species of Braconidae have now been bred in Demerara from the larva 

 of the cane-boring moth, Diatraea saccharalis : Ipobracon grenadensis, Ashm., which 

 I have previously mentioned (Ann. Mag. N.H. (8) xx, 1917, p. 244), and Ipobracon 

 saccharalis, sp. n., both of which belong to the subfamily Braconinae ; and Microdus 

 diatraeae, sp. n., which belongs to the subfamily Agathinae. 



Ipobracon saccharalis, sp. nov. 



$. Niger ; segmentis abdominalibus 5 basalibus rufis ; alis pallide fuscis, dimidio 

 basali subhyalinis ; stigmate flavo, tertio apicali fusco, cellula cubitali prima striga 

 obliqua hyalina ; venis brunneis. 



Long. 8 mm. 



<§. Face and front closely and finely punctured, densely clothed with close-lying 

 grey hairs ; vertex strongly convex, minutely punctured ; the head strongly narrowed 

 behind the eyes. Antennae about 63-jointed ; the scape finely and closely punctured, 

 the third joint distinctly longer than the fourth. Thorax and median segment very 

 finely punctured, sparsely on the dorsal surface of the thorax, very closely on the 

 mesopleurae and median segment, both of which are densely clothed with greyish 

 pubescence, which is also present, though much more sparsely, on the dorsal surface 

 of the thorax. Mesonotum narrowed anteriorly, the parapsidal furrows very deep. 

 First tergite almost as broad at the apex as long, the lateral carinae well developed, 

 the median area finely rugulose, the grooves between the median area and the lateral 

 carinae broad and transversely rugulose. Second tergite with a smooth lanceolate 

 area from the base reaching to the middle and prolonged by a carina to the apex ; 

 the areae at the anterior angles large and smooth, the groove separating them from the 

 remainder of the segment shallow and narrow ; on each side of the median area are 

 short oblique striae, beyond which the segment is finely rugose ; second suture broadly 

 arched and finely crenulate. Third and fourth tergites finely punctured-rugulose ; 

 the third with a very small triangular smooth area at the base, the areae at the 

 anterior angles large and smooth. Apical tergites very finely punctured. Nervulus 

 interstitial ; recurrent nervure received just before the first transverse cubital nervure. 

 British Guiana: Non Pared Plantation, East Coast of Demerara, 6. hi. 1913 

 (67. E. Bodkin). 



This is a parasite on the larva of Diatraea. It is more nearly allied to I. poultoni, 

 Szep., than to any other described species, but I do not think that it can be the male 

 of that species owing to differences in sculpture, and in the form of the area on 

 the second tergite. I. dolens, Cam., is also very nearly related, but the colour is 

 different and the sculpture of the abdomen is finer, the fourth tergite being finely 

 punctured, shining between the punctures, not rugulose, and there is no basal shining 

 area on the third tergite ; so that, unless the sculpture is subject to considerable 

 variation, the two cannot belong to one species. 



(C455) f 



