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Significance With decreasing cost, biodiversity genomics can be done by small laboratories, not large centers. Here, we overview the genomic landscape of an entire family of animals. By sequencing 250 representatives of skipper butterflies, we infer their phylogeny and search for genotypic determinants of phenotypic traits. We find that wing patterns are frequently convergent. This likely mimetic convergence is diversified, resulting in five distinct parallel patterns. Each of the five patterns occurs within at least two genera as well as in more distant relatives diverged more than 20 Mya. This work offers an example of how each of the nearly 6,000 families of animals will be studied in the future., For centuries, biologists have used phenotypes to infer evolution. For decades, a handful of gene markers have given us a glimpse of the genotype to combine with phenotypic traits. Today, we can sequence entire genomes from hundreds of species and gain yet closer scrutiny. To illustrate the power of genomics, we have chosen skipper butterflies (Hesperiidae). The genomes of 250 representative species of skippers reveal rampant inconsistencies between their current classification and a genome-based phylogeny. We use a dated genomic tree to define tribes (six new) and subtribes (six new), to overhaul genera (nine new) and subgenera (three new), and to display convergence in wing patterns that fooled researchers for decades. We find that many skippers with similar appearance are distantly related, and several skippers with distinct morphology are close relatives. These conclusions are strongly supported by different genomic regions and are consistent with some morphological traits. Our work is a forerunner to genomic biology shaping biodiversity research.

We assembled a complete reference genome of Eumaeus atala, an aposematic cycad-eating hairstreak butterfly that suffered near extinction in the United States in the last century. Based on an analysis of genomic sequences of Eumaeus and 19 representative genera, the closest relatives of Eumaeus are Theorema and Mithras We report natural history information for Eumaeus, Theorema, and Mithras Using genomic sequences for each species of Eumaeus, Theorema, and Mithras (and three outgroups), we trace the evolution of cycad feeding, coloration, gregarious behavior, and other traits. The switch to feeding on cycads and to conspicuous coloration was accompanied by little genomic change. Soon after its origin, Eumaeus split into two fast evolving lineages, instead of forming a clump of close relatives in the phylogenetic tree. Significant overlap of the fast evolving proteins in both clades indicates parallel evolution. The functions of the fast evolving proteins suggest that the caterpillars developed tolerance to cycad toxins with a range of mechanisms including autophagy of damaged cells, removal of cell debris by macrophages, and more active cell proliferation.

We have been field observers of tropical insects on four continents and, since 1978, intense observers of caterpillars, their parasites, and their associates in the 1,260 km 2 of dry, cloud, and rain forests of Área de Conservación Guanacaste (ACG) in northwestern Costa Rica. ACG’s natural ecosystem restoration began with its national park designation in 1971. As human biomonitors, or “insectometers,” we see that ACG’s insect species richness and density have gradually declined since the late 1970s, and more intensely since about 2005. The overarching perturbation is climate change. It has caused increasing ambient temperatures for all ecosystems; more erratic seasonal cues; reduced, erratic, and asynchronous rainfall; heated air masses sliding up the volcanoes and burning off the cloud forest; and dwindling biodiversity in all ACG terrestrial ecosystems. What then is the next step as climate change descends on ACG’s many small-scale successes in sustainable biodevelopment? Be kind to the survivors by stimulating and facilitating their owner societies to value them as legitimate members of a green sustainable nation. Encourage national bioliteracy, BioAlfa.

Whiteness, although frequently apparent on the wings, legs, antennae, or bodies of many species of moths and butterflies, along with other colors and shades, has often escaped our attention. Here, we investigate the nanostructure and microstructure of white spots on the wings of Carystoides escalantei, a dusk-active and shade-inhabiting Costa Rican rain forest butterfly (Hesperiidae). On both males and females, two types of whiteness occur: angle dependent (dull or bright) and angle independent, which differ in the microstructure, orientation, and associated properties of their scales. Some spots on the male wings are absent from the female wings. Whether the angle-dependent whiteness is bright or dull depends on the observation directions. The angle-dependent scales also show enhanced retro-reflection. We speculate that the biological functions and evolution of Carystoides spot patterns, scale structures, and their varying whiteness are adaptations to butterfly’s low light habitat and to airflow experienced on the wing base vs. wing tip.

DNA barcodes can be used to identify cryptic species of skipper butterflies previously detected by classic taxonomic methods and to provide first clues to the existence of yet other cryptic species. A striking case is the common geographically and ecologically widespread neotropical skipper butterfly Perichares philetes (Lepidoptera, Hesperiidae), described in 1775, which barcoding splits into a complex of four species in Area de Conservación Guanacaste (ACG) in northwestern Costa Rica. Three of the species are new, and all four are described. Caterpillars, pupae, and foodplants offer better distinguishing characters than do adults, whose differences are mostly average, subtle, and blurred by intraspecific variation. The caterpillars of two species are generalist grass-eaters; of the other two, specialist palm-eaters, each of which feeds on different genera. But all of these cryptic species are more specialized in their diet than was the morphospecies that held them. The four ACG taxa discovered to date belong to a panneotropical complex of at least eight species. This complex likely includes still more species, whose exposure may require barcoding. Barcoding ACG hesperiid morphospecies has increased their number by nearly 10%, an unexpectedly high figure for such relatively well known insects.

Many species of tachinid flies are viewed as generalist parasitoids because what is apparently a single species of fly has been reared from many species of caterpillars. However, an ongoing inventory of the tachinid flies parasitizing thousands of species of caterpillars in Area de Conservación Guanacaste, northwestern Costa Rica, has encountered >400 species of specialist tachinids with only a few generalists. We DNA-barcoded 2,134 flies belonging to what appeared to be the 16 most generalist of the reared tachinid morphospecies and encountered 73 mitochondrial lineages separated by an average of 4% sequence divergence. These lineages are supported by collateral ecological information and, where tested, by independent nuclear markers (28S and ITS1), and we therefore view these lineages as provisional species. Each of the 16 apparently generalist species dissolved into one of four patterns: ( i ) a single generalist species, ( ii ) a pair of morphologically cryptic generalist species, ( iii ) a complex of specialist species plus a generalist, or ( iv ) a complex of specialists with no remaining generalist. In sum, there remained 9 generalist species among the 73 mitochondrial lineages we analyzed, demonstrating that a generalist lifestyle is possible for a tropical caterpillar parasitoid fly. These results reinforce the emerging suspicion that estimates of global species richness are likely underestimates for parasitoids (which may constitute as much as 20% of all animal life) and that the strategy of being a tropical generalist parasitic fly may be yet more unusual than has been envisioned for tachinids.

Astraptes fulgerator, first described in 1775, is a common and widely distributed neotropical skipper butterfly (Lepidoptera: Hesperiidae). We combine 25 years of natural history observations in northwestern Costa Rica with morphological study and DNA barcoding of museum specimens to show thatA. fulgeratoris a complex of at least 10 species in this region. Largely sympatric, these taxa have mostly different caterpillar food plants, mostly distinctive caterpillars, and somewhat different ecosystem preferences but only subtly differing adults with no genitalic divergence. Our results add to the evidence that cryptic species are prevalent in tropical regions, a critical issue in efforts to document global species richness. They also illustrate the value of DNA barcoding, especially when coupled with traditional taxonomic tools, in disclosing hidden diversity.