^14 The Irish Naturalist, April, 1923. 



An Enemy of the Wireworm. 



In the August number of " The Entomologist," 1922, pp. 185-6, Mr. 

 Claude Morley, F.E.S., records the parasitism of the wireworm (Agriotes 

 sp. ?) by the Hymenopteron Paracodrus apterogynus Halida5^ His 

 statement is as follows : — •" Nothing has hitherto appeared respecting its 

 economy. The Irish National Museum in the autumn of 1919 sent me 

 an apterous female of this species for determination, with the intimation 

 that it had recently been bred along with identical specimens from a 

 larva of the Coleopterous genu^ Agriotes, found at Bangor, in Devon "(sic). 



As the finder of the larva I think it may be as well to record the whole 

 facts. On several occasions in the years 1 915-19 I found in my garden 

 at Ballymagee, Bangor, Co. Down (not Devon) wireworms from which 

 protruded the pupae of a parasite. In 191 8 va.Y curiosity was sufficiently 

 aroused to send one to Mr. J. A. S'dney Stendall of the museum at Belfast. 

 The insects hatched out but escaped ; but in the following year Mr. 

 Stendall was successful in rearing three or four females from another 

 wireworm which I had sent him. These eventually reached Mr. Morley, 

 through Mr. J. N. Halbert, and were named as above. Paracodrus is a 

 genus belonging to the Proctotrypidae, a division of the Hymenoptera. 



In the National Museum are two specimens of wireworm from Valencia, 

 Co. Kerrv, sent by Miss Delap, some years ago. From one protrude 

 many pupae, from the other numerous " still born " imagines of what 

 appear to me to be the same species of Paracodrus referred to above. 

 So far as I can s^e, all are wingless and all are females. Mr. Morley 

 [loc. cit.) states that the female is sometimes winged like the male, and 

 adds that the latter is by far the rarer sex. Mr. Morley also quotes 

 three old records in which wireworms had been found parasitised by 

 " a Proctotrypes," a generic name which in those days included Paracodrus. 



The question arises, how does the female Paracodrus gain access to 

 the wireworm (which is, of course, the larva of one of the so-called Click 

 Beetles) ? 



Wireworms are often found at a considerable depth in the soil and 

 are most common in old grass-land ; but I have often found them in 

 my garden at Ballymagee, basking, as it were, in the sun, just below 

 the surface of the soil, when the latter was very finely worked, as in a 

 seed or onion bed. A rake drawn over the surface of such a bed would 

 expose sometimes as many as five or six surprised and struggling wire- 

 worms. This only occurred in very hot dry weather, and possibly it is 

 under such conditions that the female Paracodrus carries out her egg-laying, 

 Paracodrus apterogynus is about a quarter of an inch in length from tip 

 of the long antennae to apex of the abdomen, exceedingly slender, 

 blackish-brown with paler legs and antennae ; the whole head and body 

 are very glossy and the head is curiously spherical. 



A. W. Stelfox. 

 National Museum. 



