Erato Phyllis Research Articles

Feeding behavior of Heliconius erato phyllis (Fabricius) (Lepidoptera: Nymphalidae) larvae on passion vines

Of the 15 species of passion vines recorded for the Rio Grande do Sul State, Brazil, nine are used by Heliconius erato phyllis (Fabricius, 1775). The larvae of this species feed preferentially on Passiflora misera H.B.K., which confers greater performance despite presenting smaller amounts of nutrients than other host plants. Thus, the performance associated with the consumption of a passion vine is possibly related not only to its nutritional content but also to the morphological and behavioral mechanisms involved in the feeding. In this study, the difficulties in accessing food imposed by the hosts (P. misera, Passiflora suberosa L., Passiflora caerulea L., Passiflora edulis Sims, and Passiflora alata Dryand.) were evaluated. Focal observations were performed every 2 min during 6-h sessions (sequential sampling), and the relative time spent for different behaviors (resting, feeding, walking, tasting, and vein cutting) was quantified on both young and old leaves. Larvae devoted more time feeding on P. misera in most cases. Larvae observed on P. alata devoted more to time resting and less time feeding, performing one or two meals of small duration, every 6 h. First instar caterpillars on old leaves of P. suberosa and P. caerulea spent more time walking, searching for a favorable feeding site. The hardness of leaves may be a limiting factor for the initial instars in this heliconian.

Kin recognition in immatures of Heliconius erato phyllis (Lepidoptera; Nymphalidae)

Females of the neotropical butterfly Heliconius erato phyllis lay eggs individually, which, after hatching into caterpillars, can be cannibalistic towards neighboring eggs. Laboratory experiments were conducted to test for kin recognition between first instar caterpillars and eggs. Two experiments were performed, putting three eggs in the vertices of an equilateral triangle made of green paper with side length of 0.5 cm. In the first experiment, two of the three eggs were full siblings; in the second experiment, one group consisted of three eggs from three independent nonrelated females, and in the other group all three eggs were full siblings. The frequency of cannibalism in experiment 1 (SSN, sibling–sibling–nonsibling) was 66% for nonrelated eggs and 34% for sibling eggs (P = 0.0018). In experiment 2, in group NNN (three nonsibling eggs) it was 83%, and for group SSS (three sibling eggs), the frequency of cannibalism was 53% (P < 0.0001). These results indicate kin recognition (caterpillar–egg). This recognition may have been important in the evolution of some of the butterfly’s adaptations, and possibly as an opportunity for kin selection.

Host-plant dependent wing phenotypic variation in the neotropical butterfly Heliconius erato

Most phytophagous insects feed on a single plant during development, and this may influence not only performance-linked traits, but also more subtle morphological differences. Insect-plant interactions are thus valuable for studying environmental influences on phenotypes. By using geometric morphometrics, we investigated the variation in forewing size and shape in the butterfly Heliconius erato phyllis reared on six species of passion vines (Passiflora spp.). We detected wing shape sexual dimorphism, for which the adaptive significance deserves further investigation. There was size as well as wing shape variation among individuals fed on different hosts. These subtle differences in shape were interpreted as environmental effects on development, which should be under weak natural selection for these traits, and therefore not strongly canalized. This result reinforces the role of plasticity on host-plant use, as well as the corresponding consequences on developmental variability among phytophagous insects. We propose that this variation can be an important factor in resource specialization and partner recognition, possibly triggering reproductive isolation and sympatric speciation in phytophagous insects. This interaction also shows itself as a good model for studying the role of environmental and interaction diversity in evolution.

Variation in Nectar and Pollen Availability, Sucrose Preference, and Daily Response in the Use of Flowers by Heliconius erato phyllis

The mechanisms mediating the use of flowers in the butterfly Heliconius erato phyllis (Nymphalidae) are poorly understood. Availability of nectar and pollen, nectar concentration, and abundance of Stachytarpheta cayennensis and Lantana camara (Verbenaceae), two flower species commonly used by H. erato phyllis in the Neotropics, as well as flower use by this butterfly species in the field were examined in southern Brazil. Under insectary conditions, the preference of H. erato phyllis for different sucrose concentrations (0, 10, 20, 40, and 80%) and the ability to associate sucrose concentrations with preferred and non-preferred flower colors were evaluated through choice tests. Lantana camara inflorescences were less abundant, but contained larger amounts of pollen and nectar than S. cayennensis, and H. erato phyllis utilized the flowers of the former species with higher frequency compared to the latter. In the choice tests, butterflies fed more intensely on 20 and 40% sucrose solutions, an interval in which the nectars of L. camara and S. cayennensis are situated, and were able to associate preferred sucrose concentrations with flower color efficiently within the color spectrum of L. camara flowers (i.e., preferred colors), but not within that of S. cayennensis (non-preferred colors). Thus, the greater use of L. camara flowers by H. erato phyllis is related to the plant’s superior floral rewards and not flower abundance, and to the cognitive abilities of these butterflies to adjust their feeding to the availability of pollen and nectar. To our knowledge, this is the first report showing sucrose preferences in a butterfly species.

Are there evidences of a complex mimicry system among Asclepias curassavica (Apocynaceae), Epidendrum fulgens (Orchidaceae), and Lantana camara (Verbenaceae) in Southern Brazil?

The goal of this paper was to test the presence of mimicry in Asclepias curassavica L., Epidendrum fulgens Brong., and Lantana camara L. The study was carried out at the Parque Estadual de Itapeva, RS, southern Brazil, from 2004 to 2006. Flowering period of each of the three species was followed up; focal observations of butterflies visiting flowers, from fixed point and during random walks were carried out. We also estimated the frequency of pollinaria removal in the orchid, as well as its mode of reproduction. All these variables were important for testing the mimicry hypothesis. Despite some temporal coincidences in the flowering period of two plants in the system, there was no statistical association among the three plants as to flowering period. Twenty-nine species of butterflies, as potential pollinators, were recorded, particularly Agraulis vanillae maculosa, Dryas iulia alcionea, Urbanus simplicius, Tegosa claudina, and Heliconius erato phyllis, which were the more frequent visitors of the three plants. There was association between the number of visits to L. camara and E. fulgens, based on Pearson correlation (r = 0.4603; n = 19; P = 0.0473). Pollinaria removal of E. fulgens was low, as measured by the percentage of removal (range: 0 - 10%). The analysis of the mode of reproduction of this orchid showed its pollinator-dependence, since no fruits were formed by spontaneous self-pollination. In contrast, the percentage of fruit set that resulted from geitonogamy and xenogamy was, in average, 86%. The results here shown are not conclusive as to the occurrence of a mimicry system among the three plants.

Courtship behavior of Heliconius erato phyllis (Lepidoptera, Nymphalidae) towards virgin and mated females: conflict between attraction and repulsion signals?

Previous observations of Heliconius erato phyllis females being intensively courted a few days after mating contradict the proposal of sexual repulsion caused by a male-transferred antiaphrodisiac. Furthermore, data on courtship in Heliconius butterflies are almost absent from the literature. In this work we aim to describe the courtship behavior of H. erato phyllis and to compare it towards virgin and mated females. Sexual interactions using both kinds of females were observed and filmed in seminatural conditions for subsequent analysis and quantification. Courtship of virgin and mated females differed qualitatively and quantitatively, but the results do not agree with the proposal of sexual repulsion. The differences found indicate that the courtship sequence towards mated females is interrupted in the transition that would lead to the behavior immediately prior to copulation, in such a way that the male continues courting the female in an intermediate phase. Preliminary tests even showed that older females, virgin or not, are much less courted by males. We suggest that there is a trade-off between an attraction pheromone, important for males to locate female pupae, and the male-transferred antiaphrodisiac, so that young, mated females may have both signals active. http://www.momo-p.com/showdetail-e.php?movieid=momo090807he01a.

On the reliability of a simple method for scoring phenotypes to estimate heritability: A case study with pupal color in Heliconius erato phyllis , Fabricius 1775 (Lepidoptera, Nymphalidae)

In this paper, two methods for assessing the degree of melanization of pupal exuviae from the butterfly Heliconius erato phyllis, Fabricius 1775 (Lepidoptera, Nymphalidae, Heliconiini) are compared. In the first method, which was qualitative, the exuviae were classified by scoring the degree of melanization, whereas in the second method, which was quantitative, the exuviae were classified by optical density followed by analysis with appropriate software. The heritability (h2) of the degree of melanization was estimated by regression and analysis of variance. The estimates of h 2 were similar with both methods, indicating that the qualitative method could be particularly suitable for field work. The low estimates obtained for heritability may have resulted from the small sample size (n = 7-18 broods, including the parents) or from the allocation-priority hypothesis in which pupal color would be a lower priority trait compared to morphological traits and adequate larval development.

Borboletas (Lepidoptera: Hesperioidea e Papilionoidea) visitantes florais no Jardim Botânico da Universidade Federal de Santa Maria, Santa Maria, RS, Brasil

Butterfl ies (Lepidoptera: Papilionoidea and Hesperioidea) visiting fl owers in the Botanical Garden of the Federal University of Santa Maria, Santa Maria, RS, Brazil. Urban environments, such as parks and gardens, may offer many alimentary resources, besides shelter and favorable conditions, for butterfl y survival. This study aimed to make an inventory of butterfl ies visiting fl owers in the Botanical Garden ofthe Federal University of Santa Maria (UFSM). From March 2006 to March 2007, the fl oral visitors were observed weekly for 2h. After 108 hours’ observations, 1114 visits by 39 butterfl y species, associated with 43 plant species (21 families), were confi rmed. Among the butterfl ies, Nymphalidae had the highest richness of species (S = 18), followed by Hesperiidae (S = 8), Pieridae (S = 7), Papilionidae (S = 4) and Lycaenidae (S = 2). The pierid Phoebis philea philea was the most frequent species (187 visits), followed by hesperiids Urbanus proteus proteus (100), U. teleus (73) and the nymphalid Heliconius erato phyllis (71). Lantana camara (Verbenaceae), Eupatorium laevigatum (Asteraceae), Russelia equisetiformis (Scrophulariaceae) and Stachytarpheta cayennensis (Verbenaceae) were the most visited plants. The Botanical Garden of UFSM is an example of an urban park that seems to provide fl oral resources for the feeding of many butterfl y species, beingalso a potential refuge for species from forest areas nearby.

Borboletas (Lepidoptera: Hesperioidea e Papilionoidea) do campus da Universidade Federal de Santa Maria, Santa Maria, Rio Grande do Sul

Este trabalho teve por objetivo investigar a composição, riqueza e diversidade das borboletas encontradas na área do campus Camobi da Universidade Federal de Santa Maria - UFSM, Santa Maria, Rio Grande do Sul. As amostragens foram realizadas bimestralmente de setembro de 2005 a setembro de 2006, com esforço amostral padronizado em cerca de sete horas/rede entomológica/ocasião. No total de 113 horas de amostragem, foram registrados 872 indivíduos, distribuídos em 89 espécies. Do total de indivíduos, 575 (65,9%) pertencem à família Nymphalidae, 174 (19,9%) a Hesperiidae, 88 (10,1%) Pieridae, 21 (2,4%) Lycaenidae, 10 (1,2%) Papilionidae e quatro (0,5%) Riodinidae. Do total de espécies, 40 (44,9%) pertencem à família Nymphalidae, 25 (28,1%) à Hesperiidae, 11 (12,4%) Pieridae, oito (8,9%) Lycaenidae, três (3,4%) Papilionidae e duas (2,3%) Riodinidae. As cinco espécies mais abundantes do campus Camobi foram Pyrgus orcus (Stoll, 1780) (N = 78) (Hesperiidae) e os Nymphalidae Hermeuptychia hermes (Fabricius, 1775) (N = 70), Anartia amathea roeselia (Eschscholtz, 1821) (N = 55), Vanessa braziliensis (Moore, 1883) (N = 51) e Heliconius erato phyllis (Fabricius, 1775) (N = 51). Destas, apenas H. hermes e V. braziliensis, consideradas comuns em campos ou ambientes abertos, não são características de ambientes perturbados. Estudos anteriores registraram mais 12 espécies de borboletas, elevando a riqueza local de espécies para 101. Apesar de estar sujeito a forte ação antrópica, o campus Camobi ainda é capaz de abrigar uma fauna expressiva de borboletas.

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

The present study examines the influence of nitrogen on growth rates, morphological and nutritional characteristics of Passiflora suberosa L., and the corresponding consequences for Heliconius erato phyllis (Fabricius) growth and oviposition. The treatments consisted of different nitrogen doses (0, 150 and 300 mg L(-1)) applied to the soil. Newly emerged larvae were individually reared in the laboratory (25+/-1 degree C) on branches of P. suberosa obtained from plants grown under the three nitrogen levels, and field collected females were submitted to oviposition choice tests. P. suberosa growth rates, leaf area and internode length increased significantly when grown with nitrogen enriched soil. P. suberosa presented significantly greater leaf toughness when grown without nitrogen addition. Leaves of this species also presented lower water content and toughness. Nitrogen addition increased the concentration of nitrogen and potassium on plant leaf tissues. The greater nitrogen concentration on plants did not affect H. erato phyllis larval survival, but led to a reduction in larval development time and increased adult size. Females significantly preferred to lay eggs in plants cultivated in nitrogen enriched soil. This choice was positively correlated with larval performance, which could be a possible explanation for the maintenance of that behaviour, as well as the choice of larger branches as reported in previous studies.

Pupal Melanization in Heliconius erato phyllis (Lepidoptera; Nymphalidae): Genetic and Environmental Effects

This paper deals with estimates of heritability and the effect of two different kinds of environment on the melanization of pupae in the butterfly Heliconius erato phyllis. The results for heritability showed greater differences when the offspring were regressed on male or female values for pupal colour. Pupal colour followed a system of discrete scores, from 2 for the light pupae to 5 for the darkest one. Estimate of the heritability (h2) was 0.44 when the average score of the siblings were regressed on the mid-parental value. When regressed on the male parent, h2 was larger (0.54), being very low when regressed on the female parent (0.09). Estimate by the analysis of variance was also 0.44 when both male and female sibs were included in the analysis (for male sibs, h2=0.43 and for female sibs, 0.47). To test for the effect of the environment, each brood was divided in three, one being the control, the second subjected to a black environment when reaching the fifth instar and the third to a white environment. Those in the black environment originated dark pupae that scored 5 or 4; for those in the white environment, there was no difference with the controls. Caterpillars when entering the prepupal stage were also subjected to the black treatment (early and late prepupal stage, respectively, for treatments called black A and black B). A significant effect was observed only when early prepupal stage was subjected to the black environment.

Absence of Learning and Local Specialization on Host Plant Selection by Heliconius erato

There is considerable interspecific variation in larval host plants (Passifloraceae) used among Heliconius erato (Lepidoptera: Nymphalidae) populations. This study evaluates the role of learning and the influence of interspecific variation in host plant attributes on such local specialization in H. erato host plant choices. Experiments were conducted under laboratory, insectary, and field conditions, with the two most widely used host plants in southern Brazil (Passiflora suberosa Linnaeus and Passiflora misera Humbold, Bonpland et Kunth). Larval feeding preference and induction were evaluated through choice tests for all instars. Oviposition was evaluated in relation to host plant preference, Hopkins host-selection principle, and conditioning time (for 3, 7, 11, or 15 days). Also, oviposition choice was tested regarding density, intemode length, and presence of intact terminal bud on P. suberosa and P. misera shoots. Both larvae and adults of H. erato phyllis showed preference for P. misera compared to P. suberosa, under all conditions. Larval feeding preference could not be induced for most instars. The Hopkins’ effect was not detected and oviposition choice could not be conditioned. Females alternated use of host plant species as a function of variation in either density or presence of terminal buds on shoots. Thus, our data indicate host plant preference in H. erato phyllis is not learned but innate. Therefore, we concluded that variation in local use of host plant by this butterfly in southern Brazil results from qualitative and quantitative variation of the passion vine species.

O estágio de ovo dos Heliconiini (Lepidoptera, Nymphalidae) do Rio Grande do Sul, Brasil

Utilizando-se da microscopia de luz e de varredura, são descritos e ilustrados os ovos dos seguintes Heliconiini (Lepidoptera, Nymphalidae) do Rio Grande do Sul (Brasil): Agraulis vanillae maculosa (Stichel, 1907), Dione juno juno (Cramer, 1779), Dione moneta moneta Hübner, 1825, Dryadula phaetusa (Linnaeus, 1758), Dryas iulia alcionea (Cramer, 1779), Philaethria wernickei (Röber, 1906), Eueides isabella dianasa (Hübner, 1806), Eueides aliphera aliphera (Godart, 1819), Heliconius ethilla narcaea Godart, 1819, Heliconius besckei Ménétriés, 1857 e Heliconius erato phyllis (Fabricius, 1775). Com base em diferenças morfológicas genéricas e ultraestruturais, associadas aos padrões de uso das plantas hospedeiras, elaborou-se uma chave dicotômica para a identificação das espécies.

Seasonal variation in larval host plants and consequences for Heliconius erato (Lepidoptera: Nymphalidae) adult body size

Abstract Adult body size, a key life history component, varies strongly within and between Heliconius erato phyllis (Lepidoptera: Nymphalidae) populations. In the present study, we determined whether seasonal variation in adult body size is temperature related and/or determined by seasonal changes of host plants (Passifloraceae) used by the larval stage. A population of H. erato phyllis located in a Eucalyptus plantation (Barba Negra Forest, Barra do Ribeiro County, Rio Grande do Sul State, Brazil) was sampled every 45 days from March 1997 to October 1998 to quantify seasonal variation in adult body size and use of larval host plants. In the laboratory, the effects of the following factors on adult body size were quantified: (i) host plant species (Passiflora misera or Passiflora suberosa); (ii) food quantity consumed by larvae (experimentally manipulated for each passion vine species); (iii) winter and summer temperatures (15 and 25°C, respectively); and (iv) the interaction between host plant species and temperature. Adults emerging during summer were larger than those emerging in other seasons. Female butterflies oviposited selectively on P. misera even when the dominant passion vine was P. suberosa. They only switched from using P. misera to P. suberosa during later autumn and winter, when P. misera vines were completely defoliated. The laboratory feeding trials with both passion vines showed a strong positive association between food quantity consumed by larvae and adult size. They also confirmed that adults are larger when their larvae are reared on P. misera than on P. suberosa. Temperature during larval development had no effect on H. erato phyllis adult size. Thus, seasonal variation of H. erato phyllis adult size in a given place is primarily determined by the availability and quality of host plant species used by the larval stage.

Morfologia externa dos estágios imaturos de heliconíneos neotropicais: III. Heliconius erato phyllis (Fabricius) (Lepidoptera, Nymphalidae, Heliconiinae)

The externaifeaturesof egg, larvaandpupa of Heliconius erato phyllis (Fabricius, 1775) are described and illustrated, based upon light and scanning electron microscopy.

Intraspecific variation in Trichogramma bruni Nagaraja, 1983 (Hymenoptera: Trichogrammatidae) associated with different hosts.

Trichogramma bruni is an insufficiently studied South American species whose limits are still not well defined. Thus, the objective of the present study was to characterize T. bruni taxonomically and to determine the association between morphological variations as well as host and habitat, based on morphological and biological studies. Specimens from the Escola Superior de Agricultura "Luiz de Queiroz" (ESALQ) collection, and from the University of California Riverside (UCR) and specimens collected from the vegetation of forest parks with native areas planted with eucalyptus in Piracicaba and Itatinga, State of São Paulo, were also analyzed. The holotype deposited at Univeridade Federal de Minas Gerais (UFMG) collection was also examined. The variability in the genital capsule of T. bruni observed both among individuals of the same progeny and among specimens from different hosts is remarkable and is mainly related to the dorsal lamina. Therefore, an association of diagnostic characters rather than the dorsal lamina alone should be used for the identification of T. bruni and intraspecific variations should be considered. The intraspecific variation observed for T. bruni is a factor that should be considered for its identification, since the influence of the environment (habitat + host) and the variation among individuals itself is responsible for the plasticity observed in the genital capsule. Heliconius erato phyllis, Hamadryas feronia, Erosina hyberniata and Mechanitis lysiminia are new hosts of T. bruni.

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

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 Aguas 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 character is not genetically based, thus being part of H. erato phyllis phenotypic plasticity.

Estrutura floral das angiospermas usadas por Heliconius erato phyllis (Lepidoptera, Nymphalidae) no Rio Grande do Sul, Brasil

FLOWER STRUCTURE OF ANGIOSPERMS USED BY HELICONIUS ERATO PHYLLIS (LEPIDOPTERA, NYMPHALIDAE) IN RIO GRANDE DO SUL STATE, BRAZIL. A field survey of flowering plants used as food resource by the adults of Heliconius erato phyllis (Fabricius, 1775) was carried out in four sites located in Rio Grande do Sul state, Brazil. Samples were taken in preserved areas of the Atlantic Rain and Myrtaceae forests, an Eucalyptus plantation, and an urban park. Adult feeding frequencies on flowers were registered monthly from December 1996 to May 1997, on plants located on previously marked 200 m long transects. Flowers on which H. erato phyllis fed in the field were collected, drawn and morphometrically characterized. Feeding was registered on flowers of twenty-three species, of which seventeen are new records for H. erato in Brazil . The use of a given plant varied among localities, as a function of its corresponding abundance. The most visited flowers were those of Lantana camara L. and Stachytarpheta cayennensis (Rich.) Vahl, followed by Dahlia pinnata Voss in the urban site. The data suggest the existence of size and shape convergence between the proboscis and the small, tubular flowers upon which H. erato phyllis feeds. They also indicate that H. erato phyllis adults have an opportunistic nectar feeding / pollen gathering habit, using several of those flowers available in a given time and locality that fit such a morphometrical pattern. Since plant species of both primitive and derived families are used, there is no indication that phylogenetic constraints play a major role in this association, nor that color of flowers, growth pattern or size of the plants are relevant in determining their use by H. erato phyllis.

Conspecific mimics and low host plant availability reduce egg laying by Heliconius erato phyllis (Fabricius) (Lepidoptera, Nymphalidae)

Oviposition response of Heliconius erato phyllis (Fabricius, 1775) (Lepidoptera, Nymphalidae) to variation in host plant availability, Passiflora suberosa Linnaeus (Passifloraceae), and to presence of conspecific eggs and larvae was determined through choice experiments performed under insectary conditions. Freeze dried, painted eggs and larvae were used as mimics for testing presence of conspecific effects. Females laid more eggs on intact P. suberosa shoots without conspecifics than on those with H. erato phyllis egg and first instar mimics in both simultaneous and sequential choice trials. Oviposition response to variation in host plant availability was determined through no-choice trials, under host plant densities varying from 0.3 to 8.3 plants per female. Number of eggs laid per plant decreased exponentially with an increase in plant availability. On the contrary, daily oviposition rates (eggs /female/day) increased with an increase in plant number, and levelled off when the number of plants available for oviposition was greater than potential fecundity of females. Thus, it is inferred from the results that females assess egg and larval load and prefer to lay eggs on shoots free from conspecifics. It is also inferred that they are able to recognize plant abundance and are unwilling to lay more than one egg per shoot even when host availability is scarce, as judged by reduction in daily oviposition rates under low host plant number. The consequences of laying isolated eggs on P. suberosa shoots are discussed from the viewpoint of intraspecific competition in the larval stage of H. erato phyllis.

Pollination of Habenaria pleiophylla Hoehne &amp; Schlechter (Orchidaceae) by Heliconius erato phyllis Fabricius (Lepidoptera, Nymphalidae)

For the first time the pollination of a poorly known, terrestrial orchid, Habenaria pleiophylla Hoehne & Schlechter, 1921 (Orchidaceae) by a passion vine butterfly, Heliconius erato phyllis (Fabricius, 1775) (Lepidoptera, Nymphalidae) is reported. Number of pollinia-carrying individuals was determined on a population of H. erato phyllis in Horto Florestal Barba Negra, Barra do Ribeiro County, Rio Grande do Sul State. The pollination mechanism was described under laboratory conditions, in association with the butterfly feeding habit and the orchid flower morphology. Habenaria pleiophylla pollinia are cemented during nectar feeding on the ventral portion of the compound eyes near H. erato phyllis proboscis base. The pollinia are transferred to the stigma of other flowers during subsequent visits. Both males and females of H. eralo phyllis frequently visit H. pleiophylla flowers in the Barba Negra Forest. About forty percent of field collected adults had attached pollinia, ranging in number from one to 19 per individual. Thus, H. eralo phyllis may play an important role in the reproductive biology of this H. pleiophylla population.