Ten species in one: DNA barcoding reveals cryptic species in the neotropical skipper butterfly Astraptes fulgerator

Abstract

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 that A. fulgerator is 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.

Fig. 1.

Newly eclosed female A. fulgerator (species LOHAMP, voucher code 02-SRNP-9770) from the ACG.

Fig. 2.

Last-instar caterpillars of 10 species in the A. fulgerator complex from the ACG. Interim names reflect the primary larval food plant and, in some cases, a color character of the adult.

Fig. 3.

NJ tree based on Kimura-2-Parameter distances for COI DNA sequences from 466 individuals of the A. fulgerator complex from the ACG. Numbers in parentheses indicate the total sample size for each interim taxon, rectangles caricature caterpillar color patterns, and black backgrounds indicate groups of ≥10 conspecifics with identical sequences.