“Darwin’s butterflies”? DNA barcoding and the radiation of the endemic Caribbean butterfly genus Calisto (Lepidoptera, Nymphalidae, Satyrinae)

Abstract

The genus Calisto Hübner, 1823 is the only member of the diverse, global subfamily Satyrinae found in the West Indies, and by far the richest endemic Caribbean butterfly radiation. Calisto species occupy an extremely diverse array of habitats, suggestive of adaptive radiation on the scale of other classic examples such as the Galápagos or Darwin’s finches. However, a reliable species classification is a key requisite before further evolutionary or ecological research. An analysis of 111 DNA ‘barcodes’ (655 bp of the mitochondrial gene COI) from 29 putative Calisto species represented by 31 putative taxa was therefore conducted to elucidate taxonomic relationships among these often highly cryptic and confusing taxa. The sympatric, morphologically and ecologically similar taxa Calisto confusa Lathy, 1899 and Calisto confusa debarriera Clench, 1943 proved to be extremely divergent, and we therefore recognize Calisto debarriera stat. n. as a distinct species, with Calisto neiba Schwartz & Gali, 1984 as a junior synonym syn. n. Species status of certain allopatric, morphologically similar sister species has been confirmed: Calisto hysius (Godart, 1824) (including its subspecies Calisto hysius aleucosticha Correa et Schwartz, 1986, stat. n.), and its former subspecies Calisto batesi Michener, 1943 showed a high degree of divergence (above 6%) and should be considered separate species. Calisto lyceius Bates, 1935/Calisto crypta Gali, 1985/Calisto franciscoi Gali, 1985 complex, also showed a high degree of divergence (above 6%), confirming the species status of these taxa. In contrast, our data suggest that the Calisto grannus Bates, 1939 species complex (including Calisto grannus dilemma González, 1987, Calisto grannus amazona González, 1987, stat. n., Calisto grannus micrommata Schwartz & Gali, 1984, stat. n., Calisto grannus dystacta González, 1987, stat. n., Calisto grannus phoinix González, 1987, stat. n., Calisto grannus sommeri Schwartz & Gali, 1984, stat. n., and Calisto grannus micheneri Clench, 1944, stat. n.) should be treated as a single polytypic species, as genetic divergence among sampled populations representing these taxa is low (and stable morphological apomorphies are absent). A widely-distributed pest of sugar cane, Calisto pulchella Lathy, 1899 showed higher diversification among isolated populations (3.5%) than expected, hence supporting former separation of this species into two taxa (pulchella and darlingtoni Clench, 1943), of which the latter might prove to be a separate species rather than subspecies. The taxonomic revisions presented here result in Calisto now containing 34 species and 17 subspecies. Three species endemic to islands other than Hispaniola appear to be derived lineages of various Hispaniolan clades, indicating ancient dispersal events from Hispaniola to Puerto Rico, Cuba, and Jamaica. Overall, the degree of intrageneric and intraspecific divergence within Calisto suggests a long and continuous diversification period of 4–8 Myr. The maximum divergence within the genus (ca. 13.3%) ...

Causes of endemic radiation in the Caribbean: evidence from the historical biogeography and diversification of the butterfly genus Calisto(Nymphalidae: Satyrinae: Satyrini)

“…Species sampling took place across the entire geographical distribution of the genus in the Greater Antilles, except for the Anegada Island where only one species occurs. Our analyses also included DNA sequences previously reported from taxa across the tribe Satyrini and Calisto [27-29,32] (Additional file 2). Species identifications were based on morphology and the DNA barcode region was used for further corroboration [64].…”

“…The following subdivision of areas was set: “PR” – Puerto Rico; “nH” – the northern Hispaniola paleoisland, including Cordillera Central/Massif du Nord, Sierra de Neiba/Chaîne des Matheux, and eastern Hispaniola; “sH” – the southern Hispaniola paleoisland, including Sierra de Bahoruco/Chaîne de la Selle and Massif de la Hotte in Tiburón Peninsula; “Ja” – Jamaica; “eC” – the eastern Cuba, including Nipe – Sagua – Baraoca and Sierra Maestra mountain ranges; “wC” – the central and western Cuba, including Guamuhaya and Guaniguanico mountain ranges; “Ba” – the Bahamas. Distributional ranges of Calisto were taken from several sources [22,27-29,33,46]. …”

“…The genus Calisto comprises 44 described species, all geographically restricted to single islands [23,26-29]; 11 distributed in Cuba, 1 in Puerto Rico, 1 in Anegada Island, 1 in Jamaica, 2 in the Bahamas and the remaining 28 species occurring in Hispaniola. Molecular data has given insight into the cryptic condition of several taxa in Hispaniola [27], as well as assisted in determining the phylogenetic relationships of Cuban taxa [28]. …”

“…Once Calisto colonized the Greater Antilles, further differentiation by vicariance [31,37], within-island diversification [28,36] or adaptive radiation [27] might have shaped the evolution of these butterflies.…”

Cuban Calisto (Lepidoptera, Nymphalidae, Satyrinae), a review based on morphological and DNA data

“…Whether extant species are able to overcome the 80 km wide Windward Passage or not remains to be verified. Sourakov and Zakharov (2011)supported the idea of dispersal events by Calisto ancestors from Hispaniola to other Greater Antillean islands; however, they only included Calisto herophile from Cuba in their study. Future studies on the entire genus Calisto will allow us to assess whether the Cuban species form a monophyletic group within the Hispaniolan clade, as a sister to the Hispaniolan clade, or whether the Cuban species are in fact not a monophyletic group.…”