Molecular Phylogenetics and Evolution 44 (2007) 154–164 www.elsevier.com/locate/ympev Phylogeographic patterns, molecular and vocal differentiation, and species limits in Schiffornis turdina (Aves) A´ rpa´d S. Nya´ri * Natural History Museum and Biodiversity Research Center, University of Kansas, 1345 Jayhawk Blvd., Dyche Hall, Lawrence, KS 66045-2454, USA Received 6 July 2006; revised 25 January 2007; accepted 17 February 2007 Available online 27 February 2007 Abstract Establishing species limits can be challenging for organisms in which few variable morphological characters are available, such as Schiffornis turdina, a Neotropical suboscine bird of long-debated taxonomic affinities. Apart from its dull plumage and secretive behav- ior, this taxon is well-known for its subtle but discrete within-species geographic variation in vocalizations. Phylogeographic reconstruc- tion based on three mitochondrial markers sampled across much of the species’ range reveals substantial structuring, concordant with recognized areas of endemism in Neotropical lowland forests. Monophyly of S. turdina was weakly supported by the combined dataset, as was the basal position of the Guyanan Shield population with regard to other S. turdina clades. Based on the results from both genetic and a preliminary, qualitative analysis of vocalizations, I recommend revised species limits to reflect more accurately the evolutionary history of this complex. Ó 2007 Elsevier Inc. All rights reserved. Keywords: Schiffornis; Aves; Phylogeography; Neotropics; Andes; Vocalizations; Species limits 1. Introduction et al., 2002; Chesser, 2004), resulting in recent recognition of a novel higher taxon, the Tityrinae (including Schiffor- Phylogeographic patterns among lowland South and nis and several other problematic suboscines). Although Central American birds have recently been explored with higher-level relationships of the Tityrinae have received the aid of molecular markers, revealing previously unap- considerable attention (Chesser, 2004; Ericson et al., preciated degrees of geographic differentiation (Aleixo, 2006), the details of variation, distribution, and species 2002, 2004; Burns and Naoki, 2004; Cheviron et al., limits of the component taxa remain poorly known 2005; Eberhard and Bermingham, 2005; Lovette, 2004; (Prum and Lanyon, 1989). Here, I focus on Schiffornis Marks et al., 2002). Such detailed studies of Neotropical turdina, a medium-sized, sexually monochromatic (Eaton, taxa have also greatly improved the picture of overall 2005) dull-colored, secretive bird distributed throughout avian diversity in the region, especially for taxa for which Neotropical humid lowland forests from southeastern few diagnosable morphological characters have made spe- Mexico south to northern Bolivia and the Atlantic Forest cies-level taxonomy problematic. Such is the case of of southeastern Brazil (Fig. 1). S. turdina, throughout its Schiffornis, an enigmatic and difficult genus including broad geographic distribution exhibits subtle but discrete (at present) 3 species that have long challenged taxono- variation in plumage coloration and vocalizations (Stiles mists (Ames, 1971; McKitrick, 1985; Prum and Lanyon, and Skutch, 1989; Ridgely and Tudor, 1994; Snow, 1989; Sibley and Ahlquist, 1985; Sibley and Monroe, 2004). 1990; Prum et al., 2000; Irestedt et al., 2001; Johansson Presently, 13 subspecies are recognized within S. turdina (Peters, 1979; Snow, 2004); although the existence of multi- * Fax: +1 785 864 5335. ple species has been suggested (Ridgely and Tudor, 1994; E-mail address: [email protected] Howell and Webb, 1995; Hilty, 2003; Snow, 2004), no 1055-7903/$ - see front matter Ó 2007 Elsevier Inc. All rights reserved. doi:10.1016/j.ympev.2007.02.020 A.S. Nya´ri / Molecular Phylogenetics and Evolution 44 (2007) 154–164 155 Fig. 1. Distribution map for Schiffornis turdina (adapted from Ridgely and Tudor, 1994; Snow, 2004) showing samples included in the genetic analysis as dotted circles. Outlines represent individual phylogroups, numbered corresponding to clades recovered through phylogenetic analyses (see Fig. 2). Inset tree provides a cross-reference to the overall phylogeographic relationships within S. turdina. rangewide treatment has as yet addressed any feature of its patterns has been established firmly (Avise, 2000), and con- phenotype or genotype. Descriptions of geographic varia- stitutes a powerful approach in cases such as the present tion in this species have focused on definitions of subspe- one, in which few diagnosable morphological characters cies in terms of subtle differences in plumage hue and are available for inferring historical relationships or estab- intensity, and body size. Plumage types range from darker, lishing species limits. A modern reconstruction of historical brownish-olive forms (S. t. veraepacis, S. t. acrolophites, patterns of geographic population structure in S. turdina S. t. rosenbergi, S. t. aenea) to brighter, rufescent forms will add an important contribution to the pool of taxa that (S. t. panamensis, S. t. stenorhyncha). Birds of S. t. olivacea, can serve as a basis for future integrative and comparative S. t. amazona, and nominate S. t. turdina are mostly phylogeographic analyses (Avise, 2000; Zink et al., 2001). uniform olive-brown overall (Ridgely and Tudor, 1994; As such, the purpose of this study is to use molecular char- Snow, 2004). acters to explore (1) monophyly of S. turdina, (2) aspects of Males are polygynous, advertising their presence on phylogeographic variation across its range, and (3) geo- widely spaced territories through syncopated, melodious, graphic structure and patterns of vocal differentiation for whistled songs, usually given at long intervals. Geographic comparison with patterns of genetic differentiation. variability of these songs is striking, ranging from two- noted whistles (S. t. veraepacis and S. t. olivacea), three- 2. Materials and methods noted, slower and more drawn-out songs (S. t. amazona) to four-noted, faster songs (S. t. panamenis and S. t. aenea; 2.1. Taxon sampling and laboratory protocols Ridgely and Tudor, 1994)(Fig. 3). Upon attracting a female by means of vocalizations, no physical courtship Schiffornis was represented in this study by 41 individu- displays are performed (Skutch, 1969; Prum and Lanyon, als; of these, 38 covered most of the range of S. turdina, 1989; Snow, 2004), which distinguishes Schiffornis from with samples from nearly every recognized subspecies manakins and cotingas, where mate choice centers around (Table 1 and Fig. 1). The nominate subspecies of the Atlan- ritualized visual displays of bright, sexually dimorphic tic Forest of southeastern Brazil, for which no fresh/frozen plumage (Prum and Johnson, 1987; Prum, 1990; Robbins, tissue was available, was sampled via a toepad from a 1983). museum study skin (FMNH 191688); laboratory work on Since vocalizations play a pronounced role in the life this sample was conducted by the Genetics Lab, Depart- cycle of this species, plumage characters may provide few ment of Systematic Biology, National Museum of Natural useful characters in understanding its variation. The utility History and National Zoological Park, following estab- of molecular markers for inferring phylogeographic lished in-house protocols (Fleischer et al., 2000, 2001). 156 A.S. Nya´ri / Molecular Phylogenetics and Evolution 44 (2007) 154–164 Table 1 Taxa included in this study, with sample sources (all museum voucher specimens), and GenBank sequence accession numbers Taxon Subspecies Sourcea Sample Locality ND2 COI cyt b Ingroup Schiffornis turdina veraepacis KUNHM 2115 Mexico, Silvituc EF458501 EF458586 EF458543 Schiffornis turdina veraepacis MZFC 14587 Mexico, Chiapas EF458499 EF458584 EF458541 Schiffornis turdina veraepacis MZFC 14589 Mexico, Chiapas EF458498 EF458583 EF458540 Schiffornis turdina veraepacis MZFC 10543 Mexico, Quintana Roo EF458500 EF458585 EF458542 Schiffornis turdina veraepacis LSUMNS 16118 Costa Rica, Puntarenas EF458504 EF458589 EF458546 Schiffornis turdina dumicola LSUMNS 9885 Panama, Chiriquı´ EF458502 EF458587 EF458544 Schiffornis turdina dumicola LSUMNS 9887 Panama, Cocle´ EF458503 EF458588 EF458545 Schiffornis turdina panamensis LSUMNS 9882 Panama, Canal Zone EF458524 EF458608 EF458567 Schiffornis turdina panamensis LSUMNS 9883 Panama, Canal Zone EF458525 EF458609 EF458568 Schiffornis turdina panamensis LSUMNS 1352 Panama, Darie´n EF458522 EF458607 EF458565 Schiffornis turdina panamensis LSUMNH 2261 Panama, Darie´n EF458523 – EF458566 Schiffornis turdina rosenbergi ANSP 2230 Ecuador, Esmeraldas EF458505 EF458590 EF458547 Schiffornis turdina rosenbergi LSUMNS 11820 Ecuador, Esmeraldas EF458506 EF458591 EF458548 Schiffornis turdina rosenbergi ANSP 3531 Ecuador, Azuay EF458507 EF458592 EF458549 Schiffornis turdina olivacea AMNH ROP 164 Venezuela, Bolivar EF458495 EF458580 EF458537 Schiffornis turdina olivacea KUNHM 1265 Guyana, Iwokrama Reserve EF458489 EF458574 EF458531 Schiffornis turdina olivacea KUNHM 3937 Guyana, N slope of Mt. Roraima EF458491 EF458576 EF458533 Schiffornis turdina olivacea KUNHM 5793 Guyana, Barima River EF458490 EF458575 EF458532 Schiffornis turdina amazona LSUMNS 7550 Venezuela, Amazonas EF458511 EF458596 EF458553 Schiffornis turdina amazona LSUMNS 20362 Brazil, Amazonas EF458494 EF458579 EF458536 Schiffornis turdina amazona LSUMNS 36666 Brazil, Rondoˆnia EF458521 EF458606 EF458564 Schiffornis turdina amazona ANSP 5792 Ecuador, Sucumbios EF458513 EF458598 EF458555 Schiffornis turdina amazona LSUMNS 2552 Peru, Loreto EF458512 EF458597