Article
To read the full-text of this research, you can request a copy directly from the authors.

Abstract

Coloration, position and movements on the plants, feeding activity, and the importance of host plant alkaloids are described. Larvae are distasteful to predators. -from Authors

No full-text available

Request Full-text Paper PDF

To read the full-text of this research,
you can request a copy directly from the authors.

... Larvae of Uresiphita reversalis have typically aposematic features. They are brown with white, black, and yellow patches laterally on each segment, feed conspicuously on terminal branches of their hosts (Bernays and Montllor, 1989), and sequester quinolizidine alkaloids (QAs) from Genista monspessulana (Papilionaceae), a major host plant in California (Montllor et al., 1990). Although the larvae excrete most of the QAs ingested, about 1% is retained and deposited in the larval cuticle, which contains about 2.5% dry weight QAs in the last larval instar (Montllor et al., 1990). ...
... The significance of predators to U. reversalis in the natural habitat was estimated in long-term observations in the field (Bernays and Montllor, 1989). Predation was estimated to account for between 15 and 40% of mortality of young larvae on Genista monspessulana, and mortality was reduced when predators were excluded. ...
... In the field, wasps (Vespidae) and hemipterans (Anthocoridae) were observed preying on larvae. In addition, Chrysoperla carnea (Chrysopidae) and unidentified spiders (Thomisidae and Salticidae) did con-sume larvae in no-choice experiments in the laboratory (Bemays and Montllor, 1989). An examination of responses of nine species of invertebrate predators to larvae of U. reversalis suggests that larvae are unpalatable to all but three (Montllor, Cornelius, and Bemays, unpublished). ...
Article
Full-text available
Larvae ofUresiphita reversalis (Guenée) (Lepidoptera: Pyralidae) sequester quinolizidine alkaloids from their leguminous hosts and store them primarily in the cuticle. Stored alkaloids are lost with the last larval molt. Extracts of late-instar larvae and of pupae were applied to larvae of the potato tuber moth,Phthorimaea operculella (Zeller) (Gelichiidae), which are normally palatable to two hymenopteran predators, the Argentine ant,Iridomyrmex humilis (Mayr) (Formicidae), and the paper wasp,Mischocyttarus flavitarsus (Sauss.) (Vespidae). Larvae ofP. operculella treated with alkaloid extracts ofU. reversalis larval exuviae, or with surface extracts of whole larvae, were deterrent to both predators, compared to untreated prey. Extracts of pupal exuviae added toP. operculella, however, were not deterrent.P. operculella larvae treated with the authentic alkaloids sparteine and cytisine were also deterrent to these hymenopteran predators. Storage of small but concentrated amounts of plant secondary compounds in the cuticle appears to be an efficacious means of defense against at least two common predators of lepidopteran larvae.
... Caterpillars of the pyralid moth Uresiphita reversalis (Guenée) feed extensively on sky-blue lupines in ridge sandhills of Florida, sometimes resulting in defoliation of individual plants. This moth is a multivoltine species recorded widely in North America, especially in coastal regions, that specializes in feeding on legumes in the tribe Genisteae (Kimball, 1965;Munroe, 1976;Bernays and Montllor, 1989;Montllor et al., 1990). The larvae (second to fifth instars) are highly aposematic: they are brightly colored, they feed in groups during daytime on exposed leaf surfaces, and they are relatively inactive even on hot days (Bernays and Montllor, 1989; J. Carrel, unpubl. ...
... This moth is a multivoltine species recorded widely in North America, especially in coastal regions, that specializes in feeding on legumes in the tribe Genisteae (Kimball, 1965;Munroe, 1976;Bernays and Montllor, 1989;Montllor et al., 1990). The larvae (second to fifth instars) are highly aposematic: they are brightly colored, they feed in groups during daytime on exposed leaf surfaces, and they are relatively inactive even on hot days (Bernays and Montllor, 1989; J. Carrel, unpubl. obs.). ...
... But field studies conducted in California reveal that, despite the presence of defensive chemicals, mortality of the first four instars is high (~70% of larvae die in the 3-4 wk required to develop from hatching to fifth instar). Much of the larval mortality is attributable directly to predation by anthocorid bugs, vespid wasps, chrysopid larvae, salticid spiders, and thomisid spiders (Bernays and Montllor, 1989). For reasons that are not fully evident, fifth instar larvae are virtually devoid of predation by arthropods, birds, and other enemies (Bernays and Montllor, 1989). ...
Article
Full-text available
Extensive observations of aposematic Uresiphita reversalis (Guenée) larvae feeding on sky-blue lupine Lupinus cumulicola Small in February in south Florida revealed a low incidence of predation by natural arthropod enemies. Three species of spiders, the wolf spiders Lycosa ceratiola Gertsch and Wallace and L. osceola Gertsch & Wallace and the crab spider Misumenops sp., rejected U. reversalis larvae that were offered to them in laboratory predation tests. However, the green lynx spider Peucetia viridans (Hentz) and the assassin bug Zelus longipes (L.) were found to feed on the caterpillars. Bioassays with the wolf spider L. ceratiola confirmed previous studies showing that the larval integument possess potent antifeedant properties, most likely because it contains quinolizidine alkaloids of dietary origin.
... S. and S. A. C., personal observations). Larvae are gregarious feeders (Bernays and Montllor 1989;Leen 1995). The gregariousness appears to result in part from the deposition of large (though variable) clutches of eggs (Leen 1995). ...
... A second mechanism for benefits of mixed-age groups could involve a reduction in predation risk. Subject to significant predation risk in other habitats (Bernays 1997), Uresiphita reversalis is warningly coloured, particularly in later instars, and is known to sequester alkaloids for defence against predators (Bernays and Montllor 1989;Montllor et al. 1990). Anti-predation benefits of gregariousness in aposematic species are well known (Hunter 2000), with one proposed mechanism of these benefits being increased signal repellence in larger groups (Gamberale and Tullberg 1998). ...
Article
Full-text available
Gregarious feeding is a common feature of herbivorous insects and can range from beneficial (e.g. dilution of predation risk) to costly (e.g. competition). Group age structure should influence these costs and benefits, particularly when old and young larvae differ in their feeding mode or apparency to predators. We investigated the relative value of gregarious feeding by aposematic larvae of Uresiphita reversalis that we observed feeding in groups of mixed ages and variable densities on wild Lupinus diffusus. In a manipulative field experiment, the survivorship and growth of young larvae were enhanced in the presence of older conspecifics, but not in large groups of similarly aged larvae. Estimates of insect damage and induced plant responses suggest that mixed-age groups enhance plant quality for young larvae while avoiding competition. We conclude that benefits of gregariousness in this species are contingent on group age structure, a finding of significance for the ecology and evolution of gregariousness and other social behaviours.
... Multiple larvae of this moth are typically found on a single L. perennis genet, and hatch from an egg cluster deposited on a leaf (Fig. 3a). Larvae of U. reversalis are highly distinctive, brightly patterned with yellow and black, and are reported to be aposematic, sequestering quinolizidine alkaloids that are present in consumed Lupinus tissues (Bernays and Montllor 1989) (Fig. 3b). Wiregrass, A.stricta, and small sprouts of turkey oak, Q. laevis, are the two most commonly encountered species of understory vegetation in the immediate vicinity of C. irus at RESMSF (personal observations; Fig. 3c ...
Article
Full-text available
The quality of habitat for a given species is fundamental to its persistence in that habitat space. Herbivorous insects often require a specific combination of host plants, floral resources, and physical features such as shelter. Identifying these different habitat features is a focus of ecology and conservation, particularly for managing rare or imperiled taxa. We investigated the patterns of microhabitat and host plant use of the rare frosted elfin butterfly, Callophrys irus, a larval host-plant specialist found in frequently disturbed sand plains, barrens, and sandhill pine-oak forests of the eastern United States. Previous studies have been conducted on populations in the Northeastern and Midwestern US, but the southern part of its range remains unstudied. Our efforts focused on a persistent C. irus colony in northeastern Florida, resulting in a geographically referenced census of larval host-plant Lupinus perennis, along with a multiple year survey of microhabitat features relevant to both C. irus adults and immatures. Results of the larval host-plant census revealed that the highest densities of host plants were located distant to the highest densities of C. irus. Hot-spot analysis confirmed the significance of this pattern, suggesting different habitat requirements for larval host-plant L. perennis and C. irus individuals in order to achieve maximum potential densities. Our survey of C. irus immatures showed a similar pattern of microhabitat affinity that was previously recorded in the Northeast and Midwestern US, including large larval host-plants, low amounts of ground cover vegetation, and the presence of some shade. Unique to our study we found that the presence of other herbivores of L. perennis such as larvae of the crambid moth Uresiphita reversalis had a negative effect on encountering C. irus immatures. Our results suggest that management that aims to conserve these species needs to include habitat factors that favor the overlap of these species and to consider where their densities are the highest.
... Examples include resting on the underside of leaves, the building and use of refuges (Tvardikova & Novotny, 2012), removing evidence of their presence by throwing frass (Weiss, 2003) or clipping damaged leaves (Edwards & Wanjura, 1989;Heinrich & Collins, 1983;Weinstein, 1990), feeding gregariously (McClure & Despland, 2011;Reader & Hochuli, 2003), reducing activity (Thaler & Griffin, 2008), emitting startle or warning sounds such as clicking or whistling (Brown, Boettner & Yack, 2007;Bura et al., 2011), regurgitating gut contents (Grant, 2006), and thrashing, rearing or dropping from the plant (Allen, 1990a;Castellanos et al., 2011;Low, McArthur & Hochuli, 2014). Morphological defenses are also pervasive and include modifications for crypsis or camouflage such as shape disruption, color matching and counter-shading (Hossie & Sherratt, 2012;Rowland et al., 2008;Stamp & Wilkens, 1993), aposematic coloration (Bernays & Montllor, 1989), as well as the presence of protective hairs or spines (Murphy et al., 2010). ...
Article
Full-text available
Herbivores employ a variety of chemical, behavioural and morphological defences to reduce mortality from natural enemies. In some caterpillars the head capsules of successive instars are retained and stacked on top of each other and it has been suggested that this could serve as a defence against natural enemies. We tested this hypothesis by comparing the survival of groups of the gumleaf skeletoniser Uraba lugens Walker caterpillars, allocated to one of three treatments: “−HC,” where stacked head capsules were removed from all individuals, “+HC,” where the caterpillars retained their stacked head capsules, and “mixed,” where only half of the caterpillars in a group had their stacked head capsules removed. We found no difference in predation rate between the three treatments, but within the mixed treatment, caterpillars with head capsules were more than twice as likely to survive. During predator choice trials, conducted to observe how head capsule stacking acts as a defence, the predatory pentatomid bug attacked the −HC caterpillar in four out of six trials. The two attacks on +HC caterpillars took over 10 times longer because the bug would poke its rostrum through the head capsule stack, while the caterpillar used its head capsule stack to deflect the bug’s rostrum. Our results support the hypothesis that the retention of moulted head capsules by U. lugens provides some protection against their natural enemies and suggest that this is because stacked head capsules can function as a false target for natural enemies as well as a weapon to fend off attackers. This represents the first demonstration of a defensive function.
... Large numbers of adults and larvae were collected by Waloff (1966). Uresiphita reversalis (Guenée) (Lep., Pyralidae) is a North American species that feeds on Cytisus and Genista as well as on lupins (Bernays & Montllor, 1989). It occurs in California and other regions of North America. ...
Article
Full-text available
Cytisus scoparius (Scotch broom) is an aggressive invader of agricultural, forestry, and conservation lands in many parts of its exotic range. Biological control programmes for Scotch broom with insects began in the USA in the 1950s, in New Zealand in 1981, and in Australia in 1990. Two insect species (Exapion fuscirostre and Leucoptera spartifoliella) have been intentionally introduced into the USA, two (Bruchidius villosus and Arytainilla spartiophila) into New Zealand and three (L. spartifoliella, B. villosus and A. spartiophila) into Australia. Also, nine broom-feeding species were accidentally introduced into North America, and one into New Zealand. Scotch broom remains a problem weed in all three regions, and other related brooms in the tribe Genisteae, also of European origin (C. striatus in North America, Genista monspessulana in North America and Australia, G. linifolia and G. stenopetala in Australia, and Spartium junceum in Australia and North America), now give cause for concern. In Europe, 243 phytophagous insects and mites are associated with Scotch broom, and from these, and species recorded from other brooms, further possible insect biological control agents have been identified. Insufficient host specificity, and the risk of damage to closely related nontarget plants, may limit the use of some oligophagous insect species. However, several host-specific insect and mite species have been identified that may contribute to managing Scotch broom throughout its exotic range. Pathogens have been identified that could be used as classical biological control agents, or developed into mycoherbicides. The development of insects, mites, and pathogens for control of broom species will contribute to the sustainable management of an important group of problem weeds.
... Nihei et al. 2002). Species such as Uresiphita reversalis, for example, are known to sequester quinolizidine alkaloid from its host plants and use it as a defence as they become aposematic or toxic to predators (Bernays & Montllor 1989;Montllor et al. 1990). ...
Article
Full-text available
In a three-hour bioassay, we tested the palatability and feeding preferences of Uresiphita maorialis (kōwhai moth) for Sophora tetraptera, Sophora microphylla and Sophora prostrata. Palatability tests showed no differences among the Sophora species. Feeding preferences, on the other hand, showed that S. tetraptera and S. microphylla leaves are preferred over S. prostrata leaves. Our results support our field observations in Wellington city parks and gardens showing that S. tetraptera and S. microphylla plants frequently have higher densities of larvae than S. prostrata
... In holometabolous insects at least, it is common that younger, smaller-bodied developmental stages are cryptic, and the aposematic species acquire their typical warning colouration in their later larval instars, or in the adult stage (Bernays & Montllor, 1989;Ulmer et al., 2003;Sandre et al., 2007). However, following the rationale of the trade-off hypothesis, one should expect also an ontogenetic change in the opposite direction, i.e. in large insects, warning colouration displayed at the intermediate stages should be replaced by a cryptic one as the body grows. ...
Article
Full-text available
While the study of colour patterns is a traditional subject of evolutionary ecology, there are various hypotheses which suffer from a lack of experimental evidence. One intriguing possibility is a trade-off between warning efficiency and detectability. After a certain size threshold, the detrimental effect of increased detectability can outweigh the benefits of warning colouration. One may thus expect corresponding patterns at the level of ontogenetic development: as juveniles grow, they should first acquire warning colouration, and then lose it again. We analysed this possibility in Orgyia antiqua, a moth species with hairy larvae which are polyphenic with respect to the intensity of warning colouration. We detected a regular change in colour patterns through larval life. Indeed, the larvae tend to display warning colouration at intermediate sizes while dull colours dominate in fully grown larvae. In aviary experiments, we confirmed that the colourful phenotype is the one that causes the strongest aversion in birds. Nevertheless, the effect was rather weak and most of the larvae were still eventually consumed when found. Unexpectedly, for human subjects, the warningly coloured larvae were harder, and not easier to find among natural vegetation, most likely due to the disruptive effect of the aposematic colour pattern. Importantly, the trend was reversed in the largest size class, suggesting that the disruptive colouration loses its advantage as the larva grows. This is consistent with the actual patterns of size-dependence of colouration. We present evidence against an alternative explanation which relates size-related change in colouration to behavioural changes prior to pupation. We conclude that even if the efficiency of the warning effect plays a role in determining the size-dependence of colouration, the pattern may be largely explained by the effects of size-dependent detectability alone.
... The forest tent caterpillar is typical in that it is brightly colored and groups certainly are conspicuous, and it is distasteful to birds (Heinrich, 1983(Heinrich, , 1993, but the relationship between grouping, coloration, chemical defense, and predation is hard to prove. Other group-living caterpillars that might benefit from collective enhancement of the aposematic signal include Uresiphita reversalis (Pyralidae) (Bernays and Montllor, 1989), D. casta (Limocodidae) (Reader and Hochuli, 2003), Pryeria sinica (Zygaenidae) (Costa, 2006), Saucrobotys futilalis (Crambidae) (Grant, 2007). ...
Article
Full-text available
Collective behavior in the forest tent caterpillar (Malacosoma disstria) meets the thermal constraints of being an early spring folivore, but introduces other constraints in food choice. These are minimized by state-dependent, inter-individual, and ontogenetic variations in responses to social cues. Forest tent caterpillars use pheromone trails and tactile communication among colony members to stay together during foraging. At the group level, these rules lead to cohesive synchronized collective nomadic foraging, in which the colony travels en masse between feeding and resting sites. This paper proposes that synchronized collective locomotion prevents individuals from becoming separated from the colony and hence permits them to reap the advantages of group-living, notably collective basking to increase their body temperature above ambient and collective defense against natural enemies. However, this cohesive behavior also implies conservative foraging, and colonies can become trapped on poor food sources. High fidelity to pheromone trails leads to strong amplification of an initial choice, such that colonies seldom abandon the first food source contacted, even if a better one is nearby. The risk of this trapping is modulated both by consistent inter-individual variations in exploratory behavior and by inner state. Colonies consisting of active-phenotype or protein-deprived individuals that explore more-off trails exhibit greater collective flexibility in foraging. An ontogenetic shift toward more independent movement occurs as caterpillars grow. This leads to colony break-up as the season advances. Selection pressures facing older caterpillars favor solitary living more than in the earlier instars. Caterpillars respond to this predictably changing environment by altering their behavioral rules as they grow.
... A dramatic correlation exists between reßex bleeding and conspicuous coloration among froghoppers. The four study species are also relatively inactive diurnal feeders with exposed feeding and mating behavior, traits consistent with an aposematic lifestyle (Bernays andMontllor 1989, McIver andLattin 1990). ...
Article
Full-text available
Reflex bleeding in New World froghoppers is described in detail for the first time. Prosapia sp. n. adults exude hemolymph from rupture lines in pretarsal pads when attacked by predators. After an assault, food access permitted replenishment of exudate volume within 6 h. A survey of New World Cercopoidea (53 species) demonstrated the behavior to be synapomorphic in the predominantly aposematic family Cercopidae, but not present in the largely cryptic Aphrophoridae and Clastopteridae. A comparative study of four species [ Iphirhina quota (Distant), Mahanarva costaricensis (Distant), P. plagiata (Distant), and Prosapia sp. n.] showed that total volume of exudate, volume per weight, and response to general versus localized assaults varied among sexes, species, and habitats. Laboratory and field bioassays failed to demonstrate mechanical or chemical deterrency. In tandem with warning odors, however, conspicuousness coloration and reflexive discharge of blood form an elaborate warning signal in cercopid froghoppers, probably functioning as a startle stimulus that permits escape by jumping.
... Even if small larvae are defended, their vulnerability in a predator attack may be too high making the signal too costly. Furthermore, the change in protective coloration may also be related to an alteration in predator species with increasing size (Dempster 1967;Bernays & Montllor 1989). ...
Article
Aposematic coloration commonly involves patterns with contrasting colours. The early larva of Parnassius apollo is uniformly black, but the later instars develop two rows of dorsal orange spots. We tested the effect of these orange markings on the conspicuousness of the last-instar larva, by manipulating larval coloration in photographs from a natural habitat and measuring how fast human subjects could discover the larva on a touch screen. In the first experiment we compared the detectability of the natural phenotype with that of manipulated uniformly black and uniformly orange variants at different distances. In the second experiment with another set of photographs we added manipulations involving enlarged and reduced spot sizes. Generally, detection time increased with distance, and decreased with the proportion of orange in the coloration. The uniformly black larvae were surprisingly hard to detect even at the closest distances, suggesting that the young black instar has an efficient camouflage. Furthermore, even a small amount of orange colour increased the conspicuousness of the larva considerably, indicating that the orange markings are costly in terms of detectability. Importantly, as the increase in detection time over distances was larger for the natural coloration than for the orange coloration, we suggest that the natural coloration may involve a distance-dependent switch from conspicuousness to camouflage with increasing distance. Thus, even though the orange markings most probably have a signalling function, the coloration is not maximized for either crypsis or conspicuousness.
... An alternative strategy involves ontogenetic colouration shifts during the growth period, allowing animals to exhibit warning colouration only at the range of body sizes where it is efficient. In insects, this is typically interpreted as meaning that young small-bodied larvae should be cryptically coloured while larger older larvae should develop conspicuous colouration (Bernays and Montllor 1989, Ulmer et al. 2003, Sandre et al. 2007). However, assuming that there is a trade-off between acceptability and detectability, it could equally be predicted that an ontogenetic change in the opposite direction should occur: in order to reduce the high level of detectability resulting from their large size, late stage individuals should exhibit cryptic coloration in place of the warning colouration displayed by intermediate stages. ...
Article
Full-text available
Kiskluse roll putukate kehasuuruse evolutsioonis erinevate värvusstrateegiate korral Käesoleva doktoriväitekirja eesmärk on hinnata kehasuurusest positiivselt sõltuva kisklusriski potentsiaali tasakaalustada paljudel putukatel leitud tugevat seost kehasuuruse ja viljakuse vahel. See võimaldaks selgitada niisuguste putukate esmapilgul mitteadaptiivselt lühikesena näivat kasvuperioodi. Uuri­misel võeti arvesse eri värvusstrateegiate mõju kisklusriski suurusest-sõltuvuse suunale ja tugevusele. Kehasuurus saab lindude vahendatud kisklusriski mõjutada kas saaklooma silmatorkavuse või kiskja eelistuste kaudu. Laborikatsetes leiti, et linnud (Parus major) ründavad meels­mini suuremaid varjevärvusega, kuid väiksemaid hoiatusvärvusega saakloomi. Saaklooma leidmise kiirus sõltus aga suurusest hoiatusvärvuse puhul tunduvalt tugevamini kui varjevärvuse korral. Hindamaks nende kahe valikusurve reaalset tulemust viidi läbi välikatsed, mis andsid mõlema värvitüübi puhul tule­museks positiivse sõltuvuse kehasuurusest. Suurus-sõltuvus oli hoiatus­värvu­sega mulaažidel aga tugevam. See lubab järeldada, et silmatorkavus mängib kiskjate eelistustest mõnevõrra suuremat rolli; need tulemused on aga vastuolus levinud arvamusega, et hoiatusvärvusega putukatel tasub kasvada suuremaks kui varjevärvuse puhul. Liigi O. antiqua kohta koostatud empiiriline optimaalsusmudel, mille aluseks on osaliselt käesoleva väitekirja kvantitatiivsed tulemused, näitas, et mitmesuguste realistlike parameetriväärtuste juures ei piisa kiskluse mõjust, et tasakaalustada pikema kasvuaja puhul oodatavat viljakuse tõusu. Ainult üsna kõrge üldise suremuse korral, kombineerituna suremuse suurusest-sõltuvusega, osutuks kauem kasvamine mitteadaptiivseks. Selles väitekirjas leitud realistlikud suremusparameetrid moodustavad olulise osa eeldustest, mis on vajalikud putukate elukäikude modelleerimiseks ja nende optimaalsuse hindamiseks. Body size evolution in insects with different colouration strategies: the role of predation risk The underlying aim of this thesis is to evaluate if positively size dependent risk of bird predation can counterbalance the high fecundity advantage of large size found in many insects, and thereby explain the seemingly nonadaptively short growth duration in these insects. In investigating this possibility, the colouration strategy of prey insects was accounted for, as it inevitably interacts with size in determining predation risk. Size dependence of the two major components of predation risk – detectability and acceptability to predators – in both cryptic and warningly coloured larvae was studied in two laboratory experiments. Great tits preferred larger cryptic prey item, but avoided larger conspicuous prey. However, detectability trials revealed that the slope of positively size-dependent detection risk was substantially steeper for conspicuous larvae. A field study was conducted to investigate the net outcome of the effects of detectability and acceptability on larval size-dependent predation rates. In both colour groups, the risk of bird predation depended positively on size, but was more strongly size-dependent in the presence of warning colouration. This suggests that the effect of detectability may exceed that of acceptability in natural situations. This study appears to contradict the assumption that aposematic insects benefit more from large size than cryptic ones. An optimality model constructed for O. antiqua, based on empirical results partly obtained from this study, predicts that, at a range of realistic assumptions, it is hard to explain the shortness of the actual growth period with predation risk. Only when combining high overall predation rate with positive size dependence, can the effects of predation explain the existing growth curves. The realistic parameters of larval predation rates estimated by this thesis constitute an important set of assumptions that are necessary for modelling and making inferences about insect life-history optimality.
Article
Full-text available
Abstract Bright colours in distasteful prey warn off predators, but processes associated with ontogenetic acquisition of warning colours and distasteful compounds have been studied in only a few organisms. Here, we study spotted lanternflies (Lycorma delicatula; Fulgoridae) that change to red colouration when they narrow their host plant preferences to primarily the tree of heaven (Ailanthus altissima; Simaroubaceae), which is chemically defended by quassinoids. In experiments, we showed that birds taste-avoided lanternflies collected on Ailanthus but not those collected on the secondary hosts. Birds also taste-avoided seeds infused with ailanthone, the main quassinoid sequestered from Ailanthus by lanternflies as shown through mass spectrometry analyses. Hence, the narrowing of host preferences by lanternflies synchronizes the timing of change to red colour with the acquisition of quassinoid defenses. A schematic graphical population-level model of these processes is provided. This is the first report of quassinoid sequestration by insects and the first evidence that Simaroubaceae plants provide defensive chemicals to insects. This is the first report of a fulgoroid insect sequestering identified chemical defenses. The results highlight the importance of the pan-tropical taxon Fulgoridae for evolutionary biology of complex aposematic strategies and for understanding the links between timing of defense sequestration, timing of host plant preference shifts, and timing of colour change.
Article
Host specificity tests were conducted on Uresiphita reversalis and to a lesser degree on U. polygonalis. First instars of U. reversalis were limited to feeding on quinolizidine-bearing tribes of fabaceous legumes. However, U. polygonalis from the Canary Islands and U. reversalis both failed to complete development on Cytisus scoparius (Genisteae) beyond the second instar. Cytisus scoparius and Cytisus striatus were never observed as hosts of U. reversalis in California during the years of this study (1984-1989). Host range of U. reversalis encompassed six quinolizidine-bearing tribes of the Fabaceae: Genisteae, Sophoreae, Thermopsidae, Bossiaeeae, Podalyreae, and Euchresteae, although the latter two tribes have not been reported as hosts in the field. Both native and introduced species in quinolizidine-bearing tribes will undoubtedly be used by U. reversalis when the opportunity arises.
Article
187 species of Pyraloidea from Emmet and Cheboygan Counties in Michigan are documented, providing the first extensive list of any microlepidopteran group for any part of the state. This list complements those of the well studied macrolepidoptera of the region, and provides a starting point for examining the remainder of the microlepidopteran fauna.
Chapter
In previous chapters the authors considered the distribution of alkaloids within the plant kingdom and how the plants synthesize, transport, and store them. In this chapter I shall concentrate on the question of the role and function of alkaloids, to what purpose they are produced.
Article
Full-text available
Caterpillars of Arsenura armida (Cramer) (Saturniidae: Arsenurinae) are diurnal nomadic foragers in early instars, maintaining aggregations within the host tree crown through the use of a trail pheromone. In the fourth instar, larvae switch foraging strategies to become nocturnal central place foragers. In central place foraging mode, the caterpillars rest by day on the trunk of the food plant, ascend to the canopy at nightfall to feed, and then return to the lower trunk by dawn, often at the same resting (bivouac) sites as used previously. Peak activity ascending to and descending from the canopy occurs in twilight. Central place foraging A. armida caterpillars do not maintain colony structure at night, but disperse in the canopy to feed singly. The caterpillars appear to use tree architecture and their trail pheromone to relocate conspecifics (which are generally confamilials) upon descending. While bivouac sites are often reused, individual caterpillars do not exhibit strict site fidelity and may go to a bivouac site different from whence they came. This shift in foraging behavior entails a concomitant change in reaction to the information content of A. armida's trail pheromone, from maintaining groups as the caterpillars move from patch to patch, to relocating distant resting sites. Diurnal resting bivouacs are probably warning displays, and we discuss this behavior in the context of A. armida's defensive ecology.
Article
Larvae ofUresiphita reversalis feed almost exclusively on legumes in the tribe Genisteae, which characteristically contain a variety of quinolizidine alkaloids. The larvae are aposematic, and onGenista monspessulana, a major host in California, they feed on the youngest leaves, at the periphery of the plant. These leaves, which were preferred over older foliage in choice tests, contained four to five times the level of alkaloid found in older leaves. The major alkaloids detected in these plants were dehydroaphylline andN-methylcytisine, together accounting for 74% of the total. Preliminary analyses showed the alkaloid profile of exuviae from larvae feeding on these plants was very similar to that of the plants. Two alkaloids, sparteine and cytisine, which are known components of some hosts ofU. reversalis, were phagostimulants for fifth-instar larvae when added to sucrose-impregnated glass-fiber disks. In addition, when sparteine was added to foliage ofG. monspessulana, effectively doubling the percent dry weight of alkaloid, the growth rate of late-instar larvae was positively affected. Cytisine added to plants had no discernible effect on growth of larvae. Alkaloid levels in larvae and in their frass were proportional to levels in the plants on which they fed. Although the majority of alkaloid was excreted, that which was sequestered by the insect was found entirely in the integument, possibly confering some protection from predators.
Article
Full-text available
Since 1988, the junior author (LJD) has studied the Cahaba lily or rocky shoals spiderlily, Hymenocallis coronaria (LeConte) Kunth, an iconic member of the amaryllis family native to central Alabama, Georgia and South Carolina. There it grows in the rocky shoal habitats of rivers and streams above the Fall Line, which is the geologic boundary between the shallower streams of the uplands and the more navigable rivers of the coastal plain. Its largest, most studied, and most revered populations are in Bibb County of central Alabama, where a Cahaba Lily Festival has been held by the town of West Blocton since May 1990 (Davenport, 1996). In the spring of 1996, Larry received photographs from a Festival participant that documented the occurrence of a very conspicuous caterpillar (Fig. 1) on the Caffee Creek population of Cahaba lilies, a large population on the main Cahaba River in the Cahaba River National Wildlife Refuge. (The Refuge, dedicated in 2004, protects over 3500 acres of a very biodiverse corridor along the Cahaba River just above its junction with the Little Cahaba River.) The caterpillars' occurrence appeared to be a passing phenomenon, however, as these herbivores were not seen in subsequent years. But during a canoe trip on the Little Cahaba River in 2006, a freshwater ecologist for the Nature Conservancy (PLF) observed extensive damage on the developing seeds, stems, and flowers of lily plants inflicted by a large population of the same black-and-white caterpillars. Given the level of damage on such a well-loved plant, we began a closer investigation of the phenomenon. From 2008 through 2011, we made a series of observations and conducted several experiments to determine whether these caterpillars constituted a substantial threat to Cahaba lilies. Because they didn't occur every year and weren't common in over 20 years of observations, we also wanted to see whether this species was a yearly resident in central Alabama or just a sporadic visitor. Furthermore, since noctuid moths typically pupate in the soil, we wanted to determine how this species could complete its life cycle given that its host plants' roots are fully submerged by at least 20 cm of river water year-round. Finally, we wanted to see if river fluctuations might influence the presence or abundance of these herbivores.
Article
This chapter discusses that modern work on alkaloid chemical ecology is highly mechanized, using gas chromatography–mass spectroscopy (GC–MS) or high-performance liquid chromatography (HPLC) with computer libraries of spectra to analyze mixtures and identify compounds. This has multiplied reports on simpler, more volatile, and more variable alkaloids in the studies of chemical ecology, since meaningful data are easy to obtain from these classes with the methods available. Although alkaloid activities are extremely varied and frequently multiple in natural systems, most seem related to the interaction of the lone pair of electrons on nitrogen with DNA synthesis, nerve function, and specific receptors. Enough exceptions are known, however, to be able to predict that many new natural and pharmacological activities of alkaloids have yet to be discovered. The chapter also discusses that it is possible that well-chosen laboratory surrogates for natural herbivores, predators, and pathogens provide reliable data on natural activity. Models are adequate predictors of effects in natural systems, but enough cases of poor correlation are known to cast suspicion on the relevance of laboratory populations to predict ecological activities in the field.
Article
. 1The larvae of the multivoltine imported willow leaf beetle, Plagiodera versicolora (Laicharting), are found in larval aggregations during the first half of the larval stage. An experimental study was conducted to test for seasonal (brood) and group size effects on larval fitness. For each of the three broods, egg group sizes of1, 4, 8, 16, 24 and 32 were established in the field and monitored for the first 6 days post-hatching.2There was no effect of group size on larval weight, but there was a significant effect of group size on survival. Individuals from group size 16 had the highest survival, which coincides with the mean natural cluster size of 15.3 eggs.3There were no significant interactions between brood and group size.4The effect of larval weight on adult fitness was determined in the laboratory and the field. Larval weight was correlated with egg production in the laboratory but not in the field.
Article
Uresiphita reversalis Guenée (Lep., Crambidae) is a North American species whose native hosts include legumes (Fabaceae) in the genera, Lupinus L. (Genisteae, Lupininae), Baptisia Vent. (Thermopsidae) and Sophora L. (Sophoreae). Several species from the Genisteae, subtribe Genistinae, have been introduced to the United States and U. reversalis has expanded its host range to include these species. Members of all of these tribes bear quinolizidine alkaloids (QA). Ovipositional and larval preferences of U. reversalis for both introduced and native species were examined. Adults and larvae prefer Genista L. and thus preference is proposed to be indirectly or directly associated with the presence of QA with higher toxicity in this genus than in other host genera. Larvae of U. reversalis are known to sequester QA, which are deterrent and toxic to their natural enemies.
Article
Full-text available
A survey of the literature and museum collections of Uresiphita indicates larval hosts are primarily quinolizidine-bearing plants in tribes of the Fabaceae. Three species, Uresiphita reversalis, U. ornithopteralis and U. polygonalis, were collected from seven genera in the Genisteae (Chamaecytisus, Genista, Lupinus, Spartium, Laburnum, Ulex and Cytisus) and from three genera in the Sophoreae (Sophora, Pericopsis and Bolusanthus). Two species, U. reversalis and U. polygonalis, were collected from three genera in the Thermopsidae (Baptisia, Anagyris and Piptanthus) and two, U. reversalis and U. ornithopteralis, were collected from two genera in the Bossiaceeae (Hovea and Templetonia). A few legume species that are not known to bear quinolizidine alkaloids were also reported. In particular, U. reversalis, U. polygonalis, and U. ornithopteralis were each collected from Acacia (Mimosaceae) in areas as widely distributed as Australia and the United States (California, Texas and Hawaii). This is a consistent anomaly in the over-all host-use pattern. Other nonleguminous species have been reported but are probably not indicative of hosts upon which development may be completed.
ResearchGate has not been able to resolve any references for this publication.