Scanning electron microscopy of the antennal sensilla in female Culicoides paraensis (Diptera: Ceratopogonidae)

Abstract

We studied by sanning electron microscopy the number, types, structure and distribution of the antennal sensilla of the medical important ceratopogonid Culicoides paraensis (Goeldi). There are about 174 sense organs on the antenmal flagellum which are classified as sensilla chaetica; sharp-tipped and blunt-tipped (type I and II) sensilla trichodea; sensilla basiconica; sensilla coeloconica; sensilla ampullacea and styloconic-type sensilla. The role of antennal sensory organs are discussed regarding the host preference of the biting midges.

Sensilla of the Antennae and Maxillary Palps ofCulicoides hollensisandC. melleus(Diptera: Ceratopogonidae)

“…On average, more sensilla chaetica (47) are found on more subsegments (1Ð13) of C. melleus than on those of C. furens (42; subsegments 1Ð 8) and C. hollensis (31; subsegments 1Ð 8). The distribution pattern of sensilla chaetica found on C. furens and C. hollensis is similar to that found on the antennae of female C. paraensis (Felippe-Bauer et al 1989), but the pattern on female C. melleus is more like that on C. impunctatus and C. nubeculosus (Blackwell et al 1992). The distribution pattern of both types of sensilla trichodea and sensilla basiconica is the same for our 3 estuarine species and C. impunctatus and C. nubeculosus (Blackwell et al 1992).…”

“…C. furens has more blunt-tipped sensilla (48) than C. hollensis (42) or C. melleus (36); whereas C. hollensis has more sharptipped sensilla trichodea (100) than either C. melleus (97) or C. furens (93); C. furens has many more sensilla basiconica (42) than C. melleus (13) or C. hollensis (10). The subsegmental distribution of sharp-tipped sensilla trichodea and basiconica on the antennae of female C. paraensis is similar to these species, but Felippe-Bauer et al (1989) found 2 types of blunttipped sensilla trichodea with distinct lengths, both occurring only on subsegments 1Ð 8.…”

“…The types of sensilla found in these studies, as well as the ultrastructure of the various sensilla were veriÞed by similar SEM and TEM studies by Blackwell et al (1992) of the antennae of both sexes of C. impunctatus (Goetghebuer) and C. nubeculosus (Meigen), pestiferous species in Scotland. Felippe-Bauer et al (1989) also conducted a SEM microscopy study of the antennae of female C. paraensis (Goeldi) in Brazil with similar results. Messaddeq et al (1989Messaddeq et al ( , 1990) conducted a systematic SEM study of the sensilla on the antennae and palpi of both sexes of C. nubeculosus.…”

“…The female antennae of female C. impunctatus and C. nubeculosus have a maximum of 241 and 254, respectively, of these sensilla (Blackwell et al 1992). The female antennal ßagellum of C. paraensis contains Ϸ174 of these sensilla (Felippe-Bauer et al 1989). In addition, to these 5 types of antennal sensilla, Felippe-Bauer et al (1989) found sensilla ampullacea on subsegments 1, 2, and 13, and 4 styloconic-type sensilla on subsegment 13 of C. paraensis.…”

“…The pattern for C. furens is 1, 5Ð 8; for C. hollensis is most commonly, 1, 11Ð13, but is also found in some specimens on subsegments 9 and 10; and for C. melleus 1, 8 Ð12, rarely also found on 7 or 13. Sensilla coeloconica are more -Bauer et al 1989). Sensilla coeloconica always occur on the distal end of subsegment 1 of both male and female C. impunctatus and C. nubeculosus (Blackwell et al 1992).…”