Isozymic and metric variation in the Lutzomyia longipalpis complex

Abstract

Male Lutzomyia longipalpis of two types from Bolivia were compared using isozyme electrophoresis and wing morphometry. One sample (ex Chiflonkaka Cave, alt. 2800 m at Toro Toro, Charcas Province, Potosi Department) was 'two-spot' phenotype males (i.e. tergites III and IV with paired pale patches of pheromone glands), whereas two other locality samples (Apa Apa and Imanaco, Sud Yungas Province, La Paz Department) were one-spot male phenotype (only tergite IV with paired pale patches). Multilocus enzyme electrophoresis (using ACON, aGPD, GPI, IDH, MDH, ME, 6PGD, PGM, LAP and PEPB) found no difference between samples from adjacent hen houses at Apa Apa. Nei's standard genetic distance between one-spot samples from Apa Apa and Imanaco (5 km apart, 1500 m alt.) was 0.001-0.002, whereas the two-spot males from Toro Toro (800 km away) showed a genetic distance of 0.081 from the one-spot males (Apa Apa and Imanaco). This genetic distance is commensurate with speciation, but may simply be intraspecific differentiation due to 'isolation by distance'. For comparative wing morphometry, we included additional material of one-spot males from Bolivia (Guyabal, Sud Yungas, La Paz), Brazil, Colombia and Nicaragua. These three other country samples were assumed to be different sibling species in the complex Lutzomyia longipalpis (Lanzaro et al., 1993). Statistics were based on univariate and multivariate analysis. The comparison between size-in and size-free canonical variate analysis (CVA) indicated that the wing morphometric divergence between one-spot and two-spot Bolivian phenotypes was not size dependent and could have taxonomic significance.

Aspects related to productivity for four generations of a Lutzomyia longipalpis laboratory colony

“…Colonies of L. longipalpis have been successfully established before (Sherlock & Sherlock 1959, Killick-Kendrick et al 1977, Ready 1978,1979, Modi & Tesh 1983, Buescher et al 1984. L. longipalpis populations from Central and South America show a great polymorphism in behavior, morphology and biochemical characters (Ward et al 1983, Hamilton et al 1996, Dujardin et al 1997, Mukhopadhyay et al 1998a, b, Dias et al 1998, Yin et al 1999. These results either lead L. longipalpis differences to be suspected as due to a complex of cryptic species (Lanzaro et al 1993, Warburg et al 1994 This work was partially supported by Capes (MSc scholarship to JFLM) and by the State Government of Roraima.…”

Lutzomyia longipalpis and the eco-epidemiology of American visceral leishmaniasis, with particular reference to Brazil: a review

“…Further evidence for the presence of cryptic species within a Lu. longipalpis complex has been provided by numerous other workers (Dujardin et al 1997, Lampo et al 1999, Uribe, 1999, Yin et al 1999, Arrivillaga & Feliciangeli 2001, Soto et al 2001, Arrivillaga et al 2002.…”

The status of the Lutzomyia longipalpis species complex and possible implications for Leishmania transmission

“…However, additional studies failed to corroborate these findings and showed that fertile crosses could occur between populations characterized as having the one-spot and the two-spot phenotypes (Ward et al 1988). Recent work by Dujardin et al (1997) indicates that the "two spot phenotype" also occurs in Paraguay and Bolivia and that the pale patch character cannot be related to transmission efficiency. Also Mukhopadhyay et al (1998a) using isozymes to study populations from Brazil, determined that the spot phenotype appears to be a polymorphic character not related to genetic isolation or differentiation at the species level.…”

“…The influence of colonization on genetic structure, and how this may relate to comparisons made between laboratory colonies, has been the subject of considerable discussion (Lanzaro et al 1993, Munsterman 1994, Lanzaro & Warburg 1995, Dujardin 1997. Mukhopadhyay et al (1997) compared the genetic profiles of 14 loci in five colonies of Lu.…”

“…longipalpis has an extensive distribution that extends from Mexico to Argentina. However, within this range its distribution is patchy, the species occur primarily in dry habitats in Central and northern South America although it is also associated with humid forest in the Amazon river basin (Lainson et al 1985, Lanzaro et al 1993, Dujardin et al 1997. A considerable degree of geographical isolation exists between the various populations of Lu.…”