October, 18!)?. I 24-9 



ELENCHUS TENUICORNIS, KIRBY, PARASITIC on a IIOMOPTEROUS 

 IJS^SECT OF THE GENUS LIBUBNIA. 



BY EDWARD SAUNDERS, F.L.S. 



On the 20th of last August, about 3.30 p.m., I was sweeping for 

 Hemiptera near Surbitou, along the side of Claygate Lane, and caught 

 a Ziburnia, which I should probably have let go had I not observed 

 that it seemed to have something attached to it posteriorly. Wishing 

 to examine it more closely, I put it into my cyanide bottle, and was 

 much astonished on looking at it, when I got home, to find that a (^ 

 Elenclius was in the act of emerging from its posterior segments, and 

 had been killed in that position. 



The capture is a peculiarly interesting one, as it settles the ques- 

 tion as to the host which nourishes Elenchus. 



Sir S. S. Saunders "Monographia Stylopidarum, &c.," Trans. 

 Ent. Soc, 1872, p. 24, says that the host was supposed by Templeton 

 to be JBombus, who, however, corrected his mistake, seeing that 

 Bombus did not occur in Mauritius where Elenchus Templetoni was 

 found. Sir S. S. Saunders suggests that the Formicidce would be more 

 probable associates, as Myrmecolax, a genus of Strepsiptera, was 

 already known to be parasitic upon them : a specimen, however, caught 

 in the very act of emergence settles the question conclusively. 



There is, I believe, only one other record of a Strepsipterous 

 parasite attacking Hemiptera^ viz., Colacina insidiator, Westw. This 

 is recorded by Prof. Westwood, Trans. Ent. Soc, 1877, p. 185, as 

 parasitic on Epora subtilis. Walk., one of the Fulgoridce. 



The very small size of the host in comparison to its parasite is 

 most remarkable, the Liburnia, which is in the nymph state, not being 

 more than 2\ mm. in length. I am not certain as to the exact species 

 it belongs to, but it is one of the pale ones, and probably allied to 

 brevipennis. The parasite is emerging from the ventral side of the 

 abdomen, but the segments are so distorted that I cannot determine 

 for certain between which two it is making its exit. The head 

 elytra and front legs are free, and the bases of the wings are visible ; 

 the ventral side of the parasite is uppermost, i. e., lies towards the body 

 of the Ziburnia ; this is apparently a matter of interest, as in the genera 

 Stylops and Hylecthrus (fide Sir S. S. Saunders) the ^ escapes from the 

 puparium with its ventral side towards the body of its host, whereas, 

 the ^ of Xenos escapes with its dorsal side towards its host. It would 

 be worth while for Hemipterists to watch for Homoptera with unusually 

 distorted bodies, as very probably now that the nature of its host is 



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