Folia Historico-Naturalia Musei Matraensis - A Mátra Múzeum Természetrajzi Közleményei 21. (1996)

Quadratum The Kestrel has got the greatest while the Red-footed Falcon and Lesser Kestrel has got the smallest quadratum. The highest size of the Red-footed Falcon, the GH, does not practically overlaps with that of the Hobby and Kestrel, and overlaps with the Merlin only to a small extent. The quadratum of the latter three species can not be separated by their size. In the case of the Eleonora's Falcon I only have partial data on a male individual, where MW =8.0 mm and CW = 3.0 mm. The ratio of the width and the length of the quadratum is different in each species (Plate V, Figure 2). The GH/GW value is extremely low in the Red-footed Falcon (the processus orbitális quadrati is long, and the proc. oticus quadrati is short), and hence the quadratum is most square in this species. The most elongated quadratum, and the highest value is found in the Hobby (proc. oticus quadrati is long) (Plate XXXV, Figures 7-10). The processus orbitális quadrati is narrower (dorso-ventral direction) in the Hobby and Red-footed Falcon than in the Merlin and Kestrel. In the Kestrel the processus orbitális is very short and wide in dorso-ventral direction (Plate XXXV, Figures 7-10). The condylus lateralis of processus mandibularis quadrati (at the cotyla quadratojugalis) is laterally slightly elongated in the Falcons (later referred to as processus quadratojugalis). This is longer in the Merlin than in the Hobby. The articular part of processus mandibularis is wider in the Hobby than in the Merlin, especially at the sulcus intercondylaris. The shape of both the articular surface and the processus quadratojugalis is different in each species (Plate XXXV, Figures 11-14). The processus mandibularis between the condylus lateralis and cond. caudalis is narrower in the Red-footed Falcon than in the rest of the species (sometimes narrower than the width measured at the cotyla quadratojugalis), and hence the MW/CW value is especially high. In the Lesser Kestrel the processus mandibularis at the cotyla quadratojugalis is also wider than at the condyli, or equals with it. In the only male Eleonora's Falcon specimen measured the MW/CW value is 2.67. In the Hobby, Merlin and Kestrel on the caudal edge of condylus caudalis of processus mandibularis quadrati there is a sharp crista, in the Red-footed Falcon this is missing. The rib connecting the condylus sqamosus and cond. proöticus at the processus oticus quadrati (incisura intercondylaris) in the Hobby and Red-footed Falcon is wider than in the Kestrel and Merlin. In the latter species this rib is the narrowest. Summary Falco subbuteo: - the processus oticus is long: the quadratum is elongated (GH/GW value is high), - the processus orbitális is narrow, - the processus mandibularis at the sulcus intercondylaris is wide, - the processus oticus at the incisura intercondylaris is wide. Falco columbarius: - the processus quadratojugalis is longest in this species, - the processus mandibularis at the sulcus intercondylaris is narrow, - the processus oticus at the incisura intercondylaris is narrow. Falco tinnunculus: - the quadratum is largest in this species, - the processus orbitális is short and wide. Falco vespertinus: - the quadratum is smallest in this species, 21