Geographical variation in larval host-plant use by Heliconius erato (Lepidoptera: Nymphalidae) and consequences for adult life history

Abstract

Adult body size, one of the most important life-history components, varies strongly within and between Heliconius erato phyllis (Lepidoptera: Nymphalidae) populations. This study determines if this variation is caused by geographical changes in host-plant used by the larval stage, whose reproductive parameters are influenced by female body size, with estimates of the corresponding heritability. The variation in adult body size was determined together with a survey of passion vine species (Passifloraceae) used by the larvae in seven localities in Rio Grande do Sul State: three located in the urban area of Porto Alegre and Triunfo Counties, two within Eucalyptus plantations (Barba Negra Forest, Barra do Ribeiro County, and Águas Belas Experimental Station -Viamão County), one in a Myrtaceae Forest (Itapuã State Park -Itapuã County) and one in the Atlantic Rain Forest (Maquiné Experimental Station -Maquiné County). Effects of female body size on fecundity, egg size and egg viability were determined in an outdoor insectary. Size heritability was estimated by rearing in the laboratory offspring of individuals maintained in an insectary. The data showed that adults from populations where larvae feed only upon Passiflora suberosa are smaller than those that feed on Passiflora misera. The larvae prefer P. misera even when the dominant passion vine in a given place is P. suberosa. Fecundity increases linearly with the increase in size of females, but there is no size effect on egg size or viability. Size heritability is null for the adult size range occurring in the field. Thus, the geographical variation of H. erato phyllis adult size is primarily determined by the type, corresponding availability and quality of host-plants used by the larval stage. Within the natural size range of H. erato phyllis, the variation related to this caracter is not genetically based, thus being part of H. erato phyllis phenotypic plasticity.Key words: body size, passion vines, heliconian butterflies, reproductive success, heritability. RESUMO

Oviposition preference and larval performance in aHeliconius erato phyllis(Lepidoptera: Nymphalidae) population from southeastern Brazil: is there a positive relationship?

“…Such a positive relationship provides some support to the preference-performance hypothesis, a well-studied phenomenon in phytophagous insects (Thompson 1988;Craig and Itami 2008;Gripenberg et al 2010) that states that females would prefer to oviposit on hosts conferring superior fitness to their offspring (Jaenike 1978;Thompson 1988). In this region, eggs have also been found on Passiflora actinia Hooker, Passiflora elegans Masters and Passiflora capsularis Linnaeus (Menna- Barreto and Araújo 1985;Périco and Araújo 1991;Rodrigues and Moreira 2002).…”

Effect of nitrogen on Passiflora suberosa L. (Passifloraceae) and consequences for larval performance and oviposition in Heliconius erato phyllis (Fabricius) (Lepidoptera: Nymphalidae)

“…According to Kerpel & Moreira (2005), the females choose preferentially Passiflora misera Humbold, Bonpland & Kunth compared to P. suberosa. Larvae fed shoots of P. misera result in larger adults, and body size is directly correlated to higher fecundity in this species (Rodrigues & Moreira 2002). According to Mugrabi-Oliveira & Moreira (1996a), other qualitative aspects of the shoot and host plant inspected by the female is the presence of an intact apical region, shoot size, leaf area and internode size.…”

Biotic Resource Needs of Specialist Orchid Pollinators

“…Heliconius species, often called passionvine butterflies, feed only on Passiflora species. Heliconius erato phyllis larvae are able to feed on a number of Passiflora species but prefer Passiflora misera Kunth on which they produce larger more fecund females (Rodrigues & Moreira, 2002), that can increase population sizes and their availability as orchid pollinators. The sole pollinator (Aeropetes tulbaghia) of South Africa's Disa uniflora uses only two species of indigenous grasses, Hyparrhenia hirta (L.) Stapf.…”