Correlated traits for dispersal pattern: Terrestrial movement of the water cricket Velia caprai (Heteroptera: Gerromorpha: Veliidae)

Abstract

Abstract. Macropterous individuals of wing polymorphic semiaquatic bugs (Heteroptera: Gerromorpha) usually occur at a high frequency if there is a need to leave an unfavorable habitat or in a generation migrating to/from an overwintering site. Velia caprai (Veliidae) is usually found in unpredictable habitats, but the macropterous morph is rare. Laboratory, mesocosm and field experiments were used to test the hypothesis that individuals of this species migrate by walking rather than by flight. Laboratory experiments that focused on the development of macropterous morph under conditions that usually stimulate the development of this morph in water striders were unsuccessful. A high temperature shortened the duration of nymphal development, but no winged specimens of Velia caprai developed in the laboratory when reared under either high or low temperatures, long or short photoperiods or on the surface of water or wet filter paper. Mesocosm experiments with apterous adults revealed they are able to walk on land. Both the males and females dispersed by walking in semi-natural conditions. Long-term field experiments using mark and recapture confirmed that this species can disperse by walking. Apterous individuals can compensate for downstream drift by upstream terrestrial migration and colonize newly established pools and ditches even several tens of meters from source sites. The development of a macropterous morph in response to environmental factors is replaced by terrestrial dispersal in V. caprai.

Differences in prey capture in semiaquatic bugs (Heteroptera:Gerromorpha)

“…The significant differences between promptness and efficiency of prey capture in gerrids and veliids can be explained at least in part in relation to their adaptations to different habitats. The behavior, life cycle and dispersal pattern of V. caprai make this species highly adapted to changing environmental conditions (Ditrich & Papáček 2009a,b; Ditrich & Koštál ). Both investigated Velia species colonize small forest streams, whereas the gerrid species used in our experiments are found mainly in lentic habitats.…”

“…It prefers forest streams, but occurs also in temporary pools, puddles and other lentic habitats (Bíró ; Ditrich et al . ; Ditrich & Papáček ). Velia caprai is univoltine or partly bivoltine prevalently with an apterous morph (Ditrich & Papáček ).…”

“…; Ditrich & Papáček ). Velia caprai is univoltine or partly bivoltine prevalently with an apterous morph (Ditrich & Papáček ). Velia gridellii is an Italian endemic species with very similar body dimensions, life history and habitat preferences as V. caprai (Cianferoni & Santini , ).…”

“…Velia caprai is a bug 6-8 mm long (Savage 1989) with a distribution restricted to Europe (Aukema & Rieger 1995). It prefers forest streams, but occurs also in temporary pools, puddles and other lentic habitats (Bíró 2003;Ditrich et al 2008;Ditrich & Papáček 2009b). Velia caprai is univoltine or partly bivoltine prevalently with an apterous morph (Ditrich & Papáček 2009b).…”

“…It prefers forest streams, but occurs also in temporary pools, puddles and other lentic habitats (Bíró 2003;Ditrich et al 2008;Ditrich & Papáček 2009b). Velia caprai is univoltine or partly bivoltine prevalently with an apterous morph (Ditrich & Papáček 2009b). Velia gridellii is an Italian endemic species with very similar body dimensions, life history and habitat preferences as V. caprai (Cianferoni & Santini 2012, 2013.…”