Szekessy Vilmos (szerk.): A Magyar Természettudományi Múzeum évkönyve 60. (Budapest 1968)

Farkas, H.: On the systematics of the family Phytoptidae (Acari: Eriophyoidea)

Fig. 1. Combinations of the dorsal setae Since, in the case of the Phytoptidae, special attention is to be paid to the number and arrangement of the dorsal setae, I submit a schematic figure of these conditions. One should not forget that, evidently, they numbered originally 2 pairs, that is, 4 setae. Of the two pairs, one is situated near the apex (one each on the right and the left side) of the shield, while the other arises near its posterior margin. These conditions are present today only in the family Phytoptidae. However, the reduction of the number of setae had already begun even within the family. Of the two pairs of bristles, the anterior one had fused to produce the solitary, frontal seta. Thus only three remained of the original four. A peculiar process evolved in the genus BoczeheUa PARKAS. Also the posterior pair of setae had vanished, and only the solitary, frontal bristle remained. To sum up, therefore, the family is characterized by having 4, 3, or 1 setae, with one pair of setae (or the solitary frontal one deriving from their fusion) invariably present on the apex of the shield. In all other Eriophyoid families, the pair of setae (or the single frontal one) on the apex of the shield had vanished without a trace, and there remained only the paired one adjacent to the posterior margin of the shield. In some cases, they, too, disappeared, and thus the shield bears no bristles at all. To facilitate the discussion of the family Phytoptidae, I submit in the followings a tabulation of the Phytoptid subfamilies showing also the number of setae on the shield. Subfamily Number of setae on shield Novophytopinae ROIVAINEN, 1947 4 Phytoptinae KEIFER, 1944 4, 3, 1 Sierraphytoptinae KEIFER, 1944 4 Nalepellinae ROIVATNEN, 1953 3 It is at once apparent that odd or even numbers of setae are concurrently present only in the subfamily Phytoptinae KEIFER. From this point of view, the subfamily is not homogeneous. To clarify the situation, another tabulation shows the genera of the subfamily Phytoptinae, as well as the number of setae on the shield. Genera of subfamily Phytoptinae Number of setae on shield Boczekelle FARKAS 1 Trisetacus KEIFER 3 Phytoptus KEIFER 4 Anciphytoptus KEIFER 4 Acathrix KEIFER 4 MackieUa KEIFER 4 Even a corsory glance will show that the genera of the Phytoptidae (and within it those of the subfamily Phytoptinae) may be subdivided into two large groups according to the presence of an odd or even number of setae on their shield. The essence