Ultrastructural Comparison of External Morphology of Immature Stages of Lutzomyia (Nyssomyia) intermedia and Lutzomyia (Nyssomyia) whitmani (Diptera: Psychodidae), Vectors of Cutaneous Leishmaniasis, by Scanning Electron Microscopy

Abstract

Lutzomyia (Nyssomyia) intermedia (Lutz & Neiva 1912) and Lutzomyia (Nyssomyia) whitmani (Antunes & Coutinho 1939) (Diptera: Psychodidae) are vectors of American cutaneous leishmaniasis in several endemic regions of Brazil. We analyzed the external morphological aspects of the immature stages of these two vectors by using scanning electron microscopy. In general, the larval stages of the two species are morphologically similar, although some differences were noted. Detailed examination of the eggs of both species revealed similar exchorionic ornamentations of unconnected parallel ridges. The larval head capsules are well defined, heavily sclerotized, and bear prominent chewing mouthparts. The abdominal segments are easily recognized by the presence of prolegs on their ventral surfaces. The morphology of the anal lobe on the terminal abdominal segment differs between the two species. We found the following three types of sensillae inserted on the antennae: (1) clavate basiconic; (2) small, blunt coeloconic; and (3) multipourous clavate coleoconic. In addition; five subtypes of trichoid sensillae were found on the larval body: (1) long, (2) short, (3) curved long, (4) brush-like, and (5) weakly brush-like. The caudal filaments located on the last abdominal segment were recognized as long trichoid sensillae. We observed pores on the surface of the clavate coelonic sensillae and on the caudal filaments that presumably function as chemoreceptors. The larvae of the two species show similarities in the lobular-form antennae of L1 larvae, which changes to digitiform in second instar (L2), L3, and L4. This study demonstrated that the external surface of the eggs and larvae of Lu. intermedia and Lu. whitmani are morphologically similar, but they can be distinguished by details in the microanatomy observed by scanning electron microscopy.

Life history of the sand fly vector Lutzomyia cruciata in laboratory conditions

“…whitmani and Lu. intermedia (Bahia et al, 2007), although in this study, the pattern of pores not was observed. However, Bahia et al (2007) and Pessoa et al (2001) report the presence of pores in these filaments.…”

“…whitmani and Lu. intermedia (Bahia et al, ), although in this study, the pattern of pores not was observed. However, Bahia et al .…”

“…whitmani and Lu. intermedia (Bahia et al, ) and other Diptera as Dermatobia hominis (Fernandes & Linardi, ) and Drosophila melanogaster (Riesgo‐Escovar et al, ).…”

Establishment of a Colony of Phlebotomus argentipes under Laboratory Conditions and Morphometric Variation between Wild-Caught and Laboratory-Reared Populations

“…However, none of the published information reports the successful colonization of sand flies under laboratory setup in Sri Lanka. e morphology of Phlebotomine sand flies including P. argentipes has been reported by several studies [15][16][17]. Although these reports provide valuable information to identify each stage of sand fly life cycle, identification of each instar of sand fly larvae still remains unclear.…”

Morphological aspects of immature stages ofMigonemyia migonei(Diptera: Psychodidae, Phlebotominae) an important vector of Leishmaniosis in South America by scanning electron microscopy

“…The use of scanning electron microscopy (SEM) has significant improved the characterization and descriptions of immature forms, and provided details of larval chaetotaxy [4,5]; ontogeny [6][7][8]; spiracles [9,10]; antennal, and mouthparts, such as the sensilla as well as caudal bristles [7,11,12]. Despite this, only a few articles have been carried out about the pupal morphology of New World phlebotomine sand flies [8,[13][14][15][16].…”