Descriptions of flea larvae (Siphonaptera: Ceratophyllidae, Leptopsyllidae) found in nests of the House Martin, Delichon urbica (Aves: Hirundinidae), in Great Britain

Descriptions are provided for the larvae of five species of fleas which parasitize the House Martin, Delichon urbica, in Great Britain. There are three species of Ceratophyllus, separated, among other characters, on the basis of an anterior comb row consisting of two setae per side (Ceratophyllus hirundinis ), and on the relative lengths and thicknesses of ventral setae on the second and third thoracic segments (long and slender in Ce. rusticus , while shorter and stout in Ce. farreni farreni ). The larva of Callopsylla waterstoni has more teeth on the mandible (6-13) than are present in the Ceratophyllus spp. examined here, and is unusual in the presence of two ventral setae on each of the ventral plates on the ninth abdominal segment. Frontopsylla laeta (Leptopsyllidae) is easily separable from the four ceratophyllids by its mandibles, each bearing three or four large, coarse teeth and by the position of the parietal setae on the head capsule, a unique arrangement as far as is known: one pair of minute parietals is located anteriorly along the frontal sutures, while the other two pairs are close together near the front of the coronal suture, which is itself much longer than is evident in ceratophyllid larvae. Descriptions for four of the five taxa are provided for the first time. A key is provided to identify larvae found in the nests of House Martins in Great Britain, including Ce. gallinae .