Quantitative morphological evidence for incipient species within Lutzomyiaquinquefer (Diptera : Psychodidae)

Morphological variation among geographic populations of the New World sandf ly Lutzomyia quinquefer (Diptera, Phlebotorninae) was analyzed and patterns defected that are probably associated with species emergence. This was ach ieved by examining the relationships of size and shape components of morpho logical attributes, and their correlation with geographic parameters. Quant itative and qualitative morphological characters are described, showing in both sexes differences among local populations from four Departments of Bol ivia. Four arguments are then developed to reject the hypothesis of environ ment as the unique sour ce of morphological variation: (I) the persistence of differences after removing the allometric consequences of size variation , (2) the association of local metric proper ties with meristic and qualita tive attributes, rather than with altitude, (3) the positive and significan t correlation between metric and geographic distances, and (4) the absence of a significant correlation between altitude and general-size of the insec ts.