Rhodnius prolixus and R. robustus (Hemiptera: Reduviidae) nymphs show different locomotor patterns on an automated...

Area of Science:

• Entomology
• Chronobiology
• Vector-borne diseases

Background:

• Circadian rhythms of adult triatomines (Chagas disease vectors) are well-studied.
• Activity patterns of triatomine nymphs, also capable of disease transmission, are less understood.
• Circadian rhythms can aid in the taxonomy of cryptic species, including disease vectors.

Purpose of the Study:

• To compare daily locomotor activity patterns of Rhodnius prolixus and Rhodnius robustus nymphs.
• To identify behavioral differences between these cryptic Rhodnius species.
• To assess the utility of activity patterns in differentiating sibling vector species.

Main Methods:

• Recorded daily locomotor activity of second- and third-instar nymphs of R. prolixus and R. robustus.
• Utilized an automated method for individual activity recording.
• Confirmed species identification using mitochondrial and nuclear markers.

Main Results:

• Both R. prolixus and R. robustus nymphs displayed bimodal locomotion patterns.
• Similar daily activity patterns were observed between the two species.
• R. prolixus nymphs were more active under light/dark cycles and showed a stronger activity rhythm in constant darkness.

Conclusions:

• Automated locomotor activity recording can differentiate sibling Rhodnius species.
• Distinct activity patterns in R. prolixus nymphs may enhance their vector capacity for Trypanosoma cruzi.
• Behavioral studies contribute to understanding vector taxonomy and epidemiology.