Seasonal variation in mate-locating activity in the desert hackberry butterfly (Asterocampa leilia; Lepidoptera: Nymphalidae)

Males of the desert hackberry butterfly occupy and defend encounter sites used in mate location. This activity is restricted to about 3 h each day, usually between 0800 and 1100. We monitored daily and seasonal changes in the number of males perched at encounter sites along a census route on 32 days during 1991 and 1992. The results indicate that males are active earlier in the mornings during summer than in spring or fall. However, they were not active at all times when air temperature and solar altitude would appear to permit perch site occupation. Daily and seasonal shifts in air temperature and solar radiation are not a sufficient proximate explanation for patterns of male behavior. Over a wide range of temperatures, females most often eclose around 0800, which suggests that the timing of female availability determines when males are active within the broad limits imposed by thermoregulatory requirements.     

Male mate-locating behavior inEuphydryas chalcedona (Lepidoptera: Nymphalidae) related to pupation site preferences

Males of the checkerspot butterfly (Euphydryas chalcedona)patrol and perch near but not on the larval foodplant in search of females. Experiments with tethered butterflies show that searching males chase virgin females for longer times than they do mated females or males. The larvae leave the larval food-plant to pupate. The correspondence between the distance from the larval foodplant to pupation sites and where males search for females suggests that male mate-locating behavior has evolved to maximize the rate of encounters with newly emerged, virgin females. These conclusions are compared to a recent analysis of butterfly mating systems by Odendaal et al. (Am. Nat.125: 673–678, 1985).     

Non-resource based territoriality in males of the butterflyXamia xami (Lepidoptera: Lycaenidae)

In the Pedregal de San Angel reserve, in Mexico City, males of the butterfly Xamia xamiperch in and defend areas with well-defined topographic limits. These areas lack concentrations of receptive females and of larvae and adult resources. One individual defends the same territory an average of 5 h/day, up to a maximum of 23 days. The same areas are used as territories by different males during the year. These areas share some characteristic features which are described. Evidence is presented in support of the hypothesis that the territories function as mating stations. A possible scenario for the evolution of this territorial mating system is advanced.     

Effects of plant odor on oviposition by the black swallowtail butterfly,Papilio polyxenes (Lepidoptera: Papilionidae)

Black swallowtail females laid more eggs on plant models treated with contact stimulants and volatiles from carrot leaves than on models treated only with contact stimulants. The volatiles enhanced landing rates and females alighted more frequently on artificial leaves treated with host volatiles than on adjacent control leaves. Volatiles from cabbage, a nonhost, inhibited landing rates on artificial leaves treated with carrot contact stimulants. Examination of antennae revealed two major types of sensilla, believed to be olfactory in function. Electroantennogram preparations responded more strongly to carrot volatiles than to cabbage volatiles and several shared responses at particular retention times to carrot volatile components eluting from a gas chromatograph. Our results are consistent with a long-standing hypothesis that behavioral responses to essential oil components characteristic of the larval food plants have facilitated host shifts in the genus Papilio.     

Host plant relationships of an endangered butterfly, Lopinga achine (Lepidoptera: Nymphalidae) in northern Europe

The aim of the present study was to evaluate—in a geographic perspective—the role of host plant as a determinant of habitat quality for Lopinga achine, a satyrine butterfly endangered over much of its European range. Laboratory trials were performed to record host choices made by the ovipositing females as well as by neonate larvae. In rearing experiments, growth performance and mortality on different host plants was determined. Oviposition was found to be indiscriminate but larvae were shown to be able to choose between host plants, with the choices made broadly consistent with growth performance of the larvae on particular hosts. Nevertheless, most grasses and sedges offered were found to support larval development reasonably well. No clear superiority of the previously suggested primary host plant Carex montana could be shown. Importantly, no differences in host plant relationships were found between the populations of Sweden, western Estonia and eastern Estonia. In particular, the larvae originating from eastern Estonian populations developed on C. montana equally well even if the plant is absent from their native habitat. In the context of species conservation, one should conclude that L. achine is polyphagous enough on various grasses and sedges so that the presence of any particular host species cannot be a critical component of habitat quality. Nevertheless, some preference to broad- and soft-leaved hosts, as well as sensitivity to host wilting, may partly explain the butterfly’s preference to moist forest habitats, further emphasizing the central role of habitat management in the conservation practice of this species. In turn, the absence of ecological differences between geographic populations should enable conservationists to successful transfer their experience across national boundaries.     

Roles of riparian and secondary forests in maintaining the near-threatened butterfly, Sasakia charonda (Lepidoptera, Nymphalidae), populations in Japan

To clarify the habitat requirements of the near-threatened butterfly, Sasakia charonda (Lepidoptera, Nymphalidae), we studied the distribution pattern of its host trees, Celtis sinensis and Celtis jessoensis, and the utilization patterns of various vegetation types by this butterfly in the Oofukasawa River basin in Hokuto City, Yamanashi Prefecture, central Japan. Two species of host trees, C. sinensis and C. jessoensis (height = 2 m or more) were found in riparian forests on sandbanks (hereinafter, riparian forest), in forest regenerated after landslides on valley walls (landslide tracks), in secondary deciduous forests consisting mainly of Quercus acutissima or Quercus serrata and in forests established at abandoned paddy fields and their periphery, where weeds and shrubs used to be mown frequently to avoid shade on the paddies before their abandonment. This suggests that they are pioneer species, and their distribution and regeneration depend on natural and/or human disturbances. Host trees above 2 m were preferred by larvae, and there were very few such trees in secondary forests. More overwintering larvae occurred in riparian forests than at other sites. The number of S. charonda adults was highest at the edge of riparian forests, and we observed a variety of behaviors such as puddling, chasing and mating there. Although the number of adult butterflies was smaller inside and at the edge of secondary forests than in riparian forests, puddling by males and roosting on the trunk of Q. acutissima or Q. serrata by females were observed more frequently there than in riparian forests. Thus, we conclude that landscapes including both riparian forests with natural disturbance and secondary forests with Quercus trees are necessary to maintain host Celtis trees and S. charonda populations.     

Bacoside production by suspension cultures of Bacopa monnieri (L.) Pennell

Cell suspension cultures of Bacopa monnieri (L.) Pennell, grown in modified MS medium, grew some 5–6 fold over 40 days. Selected cell lines produced the important saponin, bacoside A, up to 1 g/100 g dry wt after this time.     

Genetic (RAPD) Diversity between Oleria onega agarista and Oleria onega ssp. (Ithomiinae, Nymphalidae, Lepidoptera) in North-Eastern Peru

Oleria onega agarista Felder and Felder and Oleria onega ssp. nov. are two Ithomiinae subspecies from north-eastern Peru, that differ for some morphological and behavioural traits. Two contact zones are known near the town of Tarapoto: Ahuashiyacu, where both subspecies cohabit but do not seem to hybridise, and Estero (near the village of Shapaja), where they apparently hybridise. Genetic differences between the two subspecies and between populations were investigated with random amplified polymorphic DNA (RAPD) markers. Both Cluster and Principal Coordinates Analyses (CCoA and PCoA) performed using these data, provided a clear but weak discrimination between the two subspecies. Genetic diversity is much higher within the populations than between them. Moreover, the geographically more distant populations are grouped together by the genetic data. Morphological traits on the wing patterns of the hybrids are intermediary between the two butterflies subspecies, while RAPDs data place them closer to O. onega agarista than to O. onega ssp. The individuals of the Ahuashiyacu population are clearly separated into two groups, those of O. onega ssp. and O. onega agarista, by both morphology and RAPDs data. Moreover, none of those individuals show RAPD similarity with the hybrids, suggesting that hybridisation has not occurred in this population.     

Biogeographic history of the butterfly subtribe Euptychiina (Lepidoptera,Nymphalidae, Satyrinae)

Peña, C., Nylin, S., Freitas, A. V. L. & Wahlberg, N. (2010). Biogeographic history of the butterfly subtribe Euptychiina (Lepidoptera, Nymphalidae, Satyrinae).—Zoologica Scripta, 39, 243–258. The diverse butterfly subtribe Euptychiina was thought to be restricted to the Americas. However, there is mounting evidence for the Oriental Palaeonympha opalina being part of Euptychiina and thus a disjunct distribution between it (in eastern Asia) and its sister taxon (in eastern North America). Such a disjunct distribution in both eastern Asia and eastern North America has never been reported for any butterfly taxon. We used 4447 bp of DNA sequences from one mitochondrial gene and four nuclear genes for 102 Euptychiina taxa to obtain a phylogenetic hypothesis of the subtribe, estimate dates of origin and diversification for major clades and perform a biogeographic analysis. Euptychiina originated 31 Ma in South America. Early Euptychiina dispersed from North to South America via the temporary connection known as GAARlandia during Eocene–Oligocene times. The current disjunct distribution of the Oriental Palaeonympha opalina is the result of a northbound dispersal of a lineage from South America into eastern Asia via North America. The common ancestor of Palaeonympha and its sister taxon Megisto inhabited the continuous forest belt across North Asia and North America, which was connected by Beringia. The closure of this connection caused the split between Palaeonympha and Megisto around 13 Ma and the severe extinctions in western North America because of the climatic changes of the Late Miocene (from 13.5 Ma onwards) resulted in the classic ‘eastern Asia and eastern North America’ disjunct distribution.     

Beetle pollination of peacock moraeas (Iridaceae) in South Africa

The peacock moraeas are South African geophytes withIris-like flowers that are characterized by broad outer tepals with iridescent spots. Three of the seven species were studied and found to be exclusively visited and pollinated by beetles. The primary pollinators were hopliine (Scarabaeidae) beetles in the generaPeritrichia, Monochelus, Anisonyx andAnisochelus. These beetles visit flowers for nectar, pollen and mating.Peritrichia rufotibialis was the primary pollinator ofMoraea villosa, P. abdominalis was the primary pollinator ofM. tulbaghensis, whileMonochelus sp. nov. was the primary pollinator of the third species,M. neopavonia. High levels of fruit set attest to the effectiveness of these beetles as pollinators. Average fruit set ranged from 83.5 ± 34.8% (M. villosa) to 97.2 ± 11.6% (M. tulbaghensis). Average seed set in the various populations was more variable, but was also quite high, ranging from 77.3 ± 40.8 (M. villosa) to 342.2 ± 115.0 (M. neopavonia) seeds per capsule. Although hopliine beetles are abundant and diverse in southern Africa and commonly visit flowers, this is the first well-documented report of pollination by these beetles.     

Diurnal and seasonal changes in the mate-locating behavior of the satyrine butterfly <Emphasis Type="Italic">Lethe diana</Emphasis>

The time schedule of mate-locating behavior in the male satyrine butterfly Lethe diana was studied. Males displayed territorial behavior only in the afternoon, but it was not known whether they attempted to locate mates in the morning. In order for males of most butterfly species to mate with a virgin female, it would be most effective to initiate mate-locating behavior in the morning, when synchronous eclosions occur. Males of L.diana flew patrols in the morning and displayed territorial behavior in the afternoon. The cost of territorial behavior is probably less than that of patrolling, as territorial flights are shorter than those when patrolling. The temporal switching of mate-locating behavior is theoretically favored, since the reproductive value of females decreases later in the day, when males perform the less costly mate-locating behavior. Thus, the diurnal switching of male mate-locating behavior may be an adaptive strategy in response to the rapid decline in the reproductive value of females over the course of a day.     

Complete mitochondrial genome of the nerippe fritillary butterfly, Argynnis nerippe (Lepidoptera: Nymphalidae)

The complete mitochondrial genome sequence of the nerippe fritillary butterfly, Argynnis nerippe, which is listed as an endangered species in Korea, is described with an emphasis on the A+T-rich region. The 15,140-bp long circular molecule consisted of 13 protein-coding genes, two rRNA genes, 22 tRNA genes and 1 control region, known in insect as the A+T-rich region, as found in typical metazoans. The 329-bp long A+T-rich region located between srRNA and tRNA(Met) possessed the highest A/T content (95.7%) than any other region of the genome. Along with the several conserved sequences found typically in the lepidopteran insects the genome contained one tRNA(Met)-like and tRNA(Leu)(UUR)-like sequence in the A+T-rich region.     

Glacial Effects on Sequence Divergence of Mitochondrial COII of Polyura eudamippus (Lepidoptera: Nymphalidae) in China

Sequence divergence of mitochondrial COII was analyzed in 50 specimens belonging to five subspecies of Polyura eudamippus (Lepidoptera: Nymphalidae) collected from southern China. There were nine haplotypes in the 405 bp of partial COII sequence. Distribution of the five subspecies was primarily consistent with the spatial distribution of haplotypes. The K _st statistic showed genetic differentiation among these subspecies, except between the pair of P. e. kuangtungensis and P. e. formosana, which were separated by the Taiwan Strait. This is consistent with the 10,000-year history of the Taiwan Strait, not long enough for detectable differentiation. The present distribution pattern of COII haplotypes of P. eudamippus should be shaped by the alteration of Pleistocene glaciations, and Yunnan might be the refugium of P. eudamippus in the ice age, judging from the abundant haplotypes remaining. There were two routes for P. eudamippus in the postglacial expansion, one northward to Sichuan, Chongqing, and Hubei and another eastward to the southeastern coast of mainland China and Taiwan Island. Because the haplotype of butterflies on Hainan Island (P. e. whiteheadi) was completely different from that of mainland China, it was estimated that butterflies on Hainan Island might be from the Indo-China Peninsula rather than from mainland China.     

Immature stages of the butterfly Magneuptychia libye (L.) (Lepidoptera: Nymphalidae, Satyrinae)

The immature stages of the butterfly Magneuptychia libye (L.) are described, and their morphology is compared with other Neotropical Satyrinae.     

A Comparative Analysis of Mating Recognition Signals in Graylings: Hipparchia statilinus vs. H. semele (Lepidoptera: Nymphalidae, Satyrinae)

Courtship is an important character linked to fitness and can evolve in response to female mate choice, to ensure sex identity and quality of a potential mate. It can also be a major pre-mating isolating mechanism in butterflies and many other species. In this paper, aspects of the reproductive behaviour of Hipparchia statilinus are described. First, the ethogram and the sequential structure of courtship leading to copulation and female refusal behaviour are showed; second, the results are compared with the behaviour of the sympatric and syntopic species, H. semele. Sequential analysis of H. statilinus courtship showed that, once a male has started the sequence, the following steps most likely follow up to the end. Courtship seems to reflect female behaviour: the male can repeat the whole sequence or part of it more than once, waiting for female signals. The general pattern of sexual behaviour in H. semele and in H. statilinus is mainly identical: perching strategy, flight pursuit, courtship. In both species, courtship consists of a highly stereotypic sequence, and differences between sequences are primarily related to presence/absence, order and performance of steps. This study is the first step of an experimental design addressed to a better understanding of mating recognition signals in Hipparchia and provides more details to define the relative roles of phylogeny and environment in shaping boundaries among species.     

Predicted Impact of an Exotic Generalist Predator on Monarch Butterfly (Lepidoptera: Nymphalidae) Populations: A Quantitative Risk Assessment

The multicolored Asian lady beetle, Harmonia axyridis (Pallas), was recently identified as a potential hazard to monarch butterflies, Danaus plexippus (L.). A quantitative risk assessment for the potential impact of H. axyridis on D. plexippus in Minnesota corn and soybean fields was developed using risk analysis software. This assessment considered a potential worst-case scenario for the impact of H. axyridis on D. plexippus. Habitat-specific recruitment of D. plexippus eggs was determined empirically. Subsequently, simulated abundance of D. plexippus in each habitat was reduced by two classes of stage-specific mortality: predation by H. axyridis and causes other than H. axyridis. Predation was modeled as a function of D. plexippus exposure to H. axyridis, and predation rate of D. plexippus by H. axyridis. Exposure and subsequent risk varied considerably by habitat, with a low risk of H. axyridis adversely affecting D. plexippus populations developing in corn fields, but a moderate to high risk in soybean fields. Predicted rates of D. plexippus mortality attributable to H. axyridis were greater in soybean compared to corn fields, possibly due to the numerical response of H. axyridis to soybean aphid, Aphis glycines Matsumura. This study demonstrates that H. axyridis has the potential to have a strong adverse impact on D. plexippus populations. However, the likelihood of occurrence for this worst-case scenario remains uncertain. To evaluate the landscape-level risk of H. axyridis impacting D. plexippus, further data on recruitment of D. plexippus in other habitats and exposure estimates specific to additional habitats are needed.     

Host plant conspicuousness and the distribution of eggs and larvae in the butterfly,Anthocharis scolymus (Lepidoptera: Pieridae)

We investigated how the distribution pattern of eggs and larval on the host plant, Turritus glabra, was influenced by the oviposition behavior of the pierid butterfly Anthocharis scolymus. Females searched for the host plants visually and they frequently approached taller host plants with sparse surrounding vegetation. After encountering host plants, oviposition behavior of females was independent of host plant characteristics such as height, density, and type of surrounding vegetation. A female laid eggs singly on a host plants. Most females appeared to lay their eggs regardless of the presense of eggs on the host plant. Consequently egg and larva tended to be abundant on conspicuous host plants as measured by height or relative isolation from other plants. However, overcrowding of eggs on an individual host decreased the survival rate of larvae.     

The adaptive significance of alpine melanism in the butterfly Parnassius phoebus F. (Lepidoptera: Papilionidae)

Summary The adaptive significance of alpine melanism, the tendancy for insects to become darker with increased elevation and latitude, was investigated using the butterfly Parnassius phoebus. The effects on temperature dependent activity of five components of overall wing melanism, as well as size, were examined. The components of wing melanism examined were the transparency of the basal hindwing and distal fore-wing areas, the width of the black patch in the basal hind-wing area and the proportion of black to white scales in that area, and the proportion of the distal fore-wing covered by predominantly black scaling.The body temperature of dead specimens was correlated with air temperature, solar radiation, the width of the black patch at the base of the wings, and the proportion of black to white scales at the base of the wings. The minimum air temperatures and solar radiation levels required for initiation of flight did not vary with wing melanism of P. phoebus, in contrast to the results found for Colias butterflies by Roland (1982). However, under environmental conditions suitable for flight initiation, males with a higher proportion of black to white scales in the basal area of the hind-wing, and wider basal black patches, spent a greater proportion of time in flight at low air temperatures and low insolation. Increased basal wing melanism was also associated with increased movement of males within a population. In contrast, melanism in the distal area of the wings has no effect on activities which are dependant on body temperature. The amount of time spent feeding did not vary with differences in wing melanism. I suggest that in dorsal basking, slow-flying butterflies (Parnassius) basal wing color affects body temperature primarily during flight (rather than while basking), such that butterflies with darker wing bases cool down less rapidly because they absorb more solar radiation during flight.     

Comparing the effects of the exotic cactus-feeding moth, Cactoblastis cactorum (Berg) (Lepidoptera: Pyralidae) and the native cactus-feeding moth, Melitara prodenialis (Walker) (Lepidoptera: Pyralidae) on two species of Florida Opuntia

This study examined the effects of the native cactus moth borer, Melitara prodenialis, and the invasive cactus moth borer, Cactoblastis cactorum, on two common cactus species, Opuntia stricta and O. humifusa at coastal and inland locations in central Florida. Opuntia stricta were present only at coastal sites and O. humifusa were present at coastal and inland sites. Throughout the duration of the study, coastal plants were subject to damage solely by C. cactorum and inland plants solely by M. prodenialis. Results showed marginally significantly higher numbers of eggsticks on O. stricta than O. humifusa and significantly higher numbers at coastal sites than at inland sites. There was also significantly higher moth damage on O. stricta than O. humifusa and at coastal sites than inland sites, but not significantly so. However, there was a higher level of plant mortality for O. humifusa than for O. stricta and a significantly higher level of cactus mortality at inland sites when compared to coastal sites. This increased mortality may be due to increased attack by true bugs, Chelinidea vittiger, and by Dactylopius sp., combined with attack by M. prodenialis. Inland plants also tended to be smaller than coastal plants and could be more susceptible to the combined effects of all insects. Further long-term research on coastal cactus survival when attacked and unattacked by Cactoblastis is necessary to fully determine the effects of this moth on Opuntia survival.     

Visual mate-searching behaviour in the evening brown butterfly, Melanitis leda (L.) (Lepidoptera: Nymphalidae)

Abstract As in most animals, male butterflies are generally the more proactive sex with respect to seeking out mating opportunities. In most cases, males conduct their search sometime between mid-morning and mid-afternoon, but a few species are active only before dawn or after sunset. These crepuscular species offer a good opportunity to study how males deal with markedly different visual and thermal conditions. Here, I present data from a 5-month behavioural study of male Melanitis leda (Nymphalidae) at a mate-encounter site in tropical Australia. Males of this species defended perching locations along a forest edge in a similar manner to other diurnally active territorial nymphalids. They generally arrived at these sites after sunset and arrived earlier on evenings that darkened earlier. Actively mate-locating males were only seen at the site during a 25−35 min evening period, during which ambient light levels ranged between 50 and 2600 lux. Only 27% of marked territory residents were recorded again at their location of capture, but fidelity in this 'resighted' group ranged up to 23 days. A sample of males, captured under ambient temperatures of 24.0−27.2°C, maintained a mean thoracic excess of 8.25 ± 0.73°C, but did not appear to 'shiver' in the manner of other crepuscular species. Males courted conspecific females and one mating was observed. This species is an excellent candidate for further research into the evolution of mating tactics in crepuscular butterflies.