Frogs of the genus Colostethus (Anura; Dendrobatidae) in the Andes of northern Peru

2004·19.5 MB·English

by  William E Duellman

Papers
Scientific
Museum
Natural History
The University of Kansas
15 November 2004 Number 35:1-49
Frogs of the Genus Colostethus (Anura; Dendrobatidae)
in the Andes of Northern Peru
^ACz.
By ^^gp,AR^
William E. Duellman
Nntuivl H;s/i)n/ MusciDii and Biodiversity Research Ce)iter
The Universiti/ofKansas
Laioreiiee, Ka)isas 66045-7561 USA
CONTENTS
ABSTRACT 2
RESUMEN 2
INTRODUCTION
3
Acknowledgments 3
MATERIALS AND METHODS 4
ANDES OF NORTHERN PERU 4
SUMMARYOF TAXONOMIC CHARACTERS 5
IDENTIFICATION OF SPECIES 10
Key tothe Species 10
Clave de las Especies 11
ACCOUNTS OFTHE SPECIES 11
Cohistethus aerii^^iiiosiis new species 11
Colostethus argyro^iaster Morales and Schulte 13
Colostethus craspedoeeys new species 16
Colostethus elachyhistus Edwards 18
Colostethus eleutherodacti/his new species 21
Colostethus idioiuelus Rivero 23
Colostethus iiisulatus new species 24
Colostethus leueophaeus new species 26
Colostethus luitteniieieri Rivero 28
Colostethus lu'xipus Frost 30
Colostethus oniatus Morales 32
©Natural History Museum,TheUniverMt\ ofKcinsds , rAmn'^.r'-'lV'& i-Uu.v-ieJ ISSN No. 11)94-0782
Museum
Univors.iV
Harvard
Scientific Papers, Natural History Museum, The University of Kansas
Colosti'tlnifi pocciloiiotiifi Rivero 33
Colostetlnis piilchcrriinu^ new species 34
Colostethus sordidatu^ new species 35
Colostctlnif i^piloto;^nfti'r new species 37
Colostethus s\/lvaticiis Barbour and Noble 38
Colostethus utcubambensis Morales 40
Status of Phyllobatesperuviamis Melin 41
DISCUSSION...! 41
LiPE History andTadpoles 41
Ecology 43
Bioceography 44
LITERATURE CITED 45
APPENDICES 46
Appendix 1. Specimens and Localities 46
Appendix 2. Gazetteer 48
abstract Seventeenspeciesofthedendrobatid froggenusColostethusarerecognized intheAndes
and adjacent lowlands in northern Peru. Nine of these species have been reported previously from
the regionand eightaredescribed as new. Tadpolesofeightspecies aredescribed and illustrated, and
growth trajectories of six species of tadpoles are compared. The greatest diversity of Colostethus is in
humid montaneforestsin thenorthern partoftheCordilleraCentral, wherefivespeciesoccurateleva-
tionsabove 1600m;sixotherspeciesoccuratelevationsbelow 1000 m.Twoofthesealsorange intothe
valley ofthe Ri'o Maranon, where two additional species occur. Colostethus elachyhistus is widespread
in theAndes in southern Ecuador and in the northern part ofthe Cordillera Occidental, including the
Cordillera de Huancabamba, the higher parts of which are inhabited by C. sylvaticus. Colostethus ela-
chyhistusandC. nexipus are the only speciesthatoccur in Ecuadorand northern Peru. Seveninstances
ofsympatry reveal slight differences in size between co-occurring species at most ofthese sites.
Key Words: Anura, Dendrobatidae, Colostethus, new species, tadpoles, Andes of northern Peru, tax-
onomy,biogeography.
RESUMEN Se reconocen diecisieteespeciesdedendrobatidos del generoColostethus en losAndesy
tierrasbajasadyacentes del norte del Peru. Nueve de estas especies han sido reportadas previamente
para la zona y se describen ocho especies nuevas. Los renacuajos de ocho especies son descritos e
ilustrados; se compara los patrones de crecimiento de los renacuajos de seis especies. La mas alta
diversidad de Colostethus se encuentra en los bosc]ues humedos montanos de la region norte de la
CordilleraCentral,endondehabitancincoespeciesporsobrelos1000m;dosdeestasespeciestambien
se encuentran en el valle del n'o Maranon; en el mencionado valle existen dos especies adicionales.
Colostethus elachyhistus habita en los Andes del sur del Ecuador y en la region norte de la Cordillera
Occidental del Peru, incluyendo la Cordillera de Huancabamba, en cuyas partes mas altas seencuen-
tra C. sylvaticus. Colostethus elachyhistus y C. nexipus son las linicas especies que se encuentran en el
Ecuadoryenel nortedel Peru. Sieteejemplosdesimpatn'a revelan pcquenasdiferenciasenel tamano
deespeciesen la mayorfa de los lugares mencionados.
Palabras Clave: Anura, Dendrobatidae, Colostethus, nuevas especies, renacuajos, Andes del norte del
Peru, taxonomfa, biogeografi'a.
COLOSTETHUS OV NORTHERN PeRU
INTRODUCTION
Frogs currently allocated to the genus Colo$ti'tliu> The extensive collections from northern Peru include
are especiallv speciose in the Andes of Colombia (Ruiz- eight new species described herein and the first Peruvian
Carranza et al., 1996; Rivero and Serna, 2000; Grant and records of another species previously known only from
Ardila-Robayo, 2002) and Ecuador (Coloma, 1995; Santos Ecuador.Thepurposesofthispaperaretodescribethenew
et al., 2003). Many fewerspecies ha\'e been reported from species and to review the species of Colostethiis known to
the highlands of northern Peru (Rivero, 1991; Duellman occurintheAndesand associated mountain ranges, inter-
andWild, 1993;MoralesandSchulte, 1993;Morales, 1994). vening valleys, and the immediately adjacentAmazonian
Field parties from the Natural History Museum at The lowlands in northern Peru (departamentos ofAmazonas,
University of Kansas worked in the Andes of northern Cajamarca, Piura, and San Martin). Despite the large
Peru (departamentos de Amazonas, Cajamarca, Piura, number of specimens now known from the region, our
and San Martin) in 1970, 1975, 1979, 1989, and 1991. This knowledgeoftheanuransintheAndesofnorthern Peruis
fieldwork produced morethan 400 specimens ofColostc- farfromcomplete. Morethoroughcollectingcertainly will
thus that are deposited in the Natural History Museum extendtheknownrangesofmanyspecies,andtheexplora-
at The University of Kansas and in the Museo de Histo- tionofpreviouslyuncollectedvalleysandmountainslopes
ria Natural at the Universidad Nacional Mayor de San surely will reveal additional species, as is evident by the
Marcos in Lima, Peru. In addition to these specimens, discoveriesinothertaxa (e.g.,Centrolenidaeby Duellman
additional material was collected by: Kenneth E, Camp- and Schulte, 1993, and Eleutherodactylusby Duellman and
bell in 1970 and deposited in the Florida State Museum; Pramuk, 1999).
Richard Thomas and others in the 1970s and deposited Acknowledgments
in the MuseumofNaturalScienceatLouisianaState Uni- —
versity (somespecimenstransferred toThe University of I am indebted to mv field companions Thomas J.
Kansas); RussellA. Mittermeierin 1978 and deposited in Berger,DavidC. Cannatella, FernandoM. CuadrosV., Mi-
the MuseumofComparativeZoologyat Harvard Univer- chaelE. Morrison, Rainer—Schulte,JohnE.Simmons, Linda
sity; and Rainer Schulte, a resident ofTarapoto, Peru, in Trueb, and JohnJ. Wiens whoseefforts resulted in man\'
the1980sand deposited inthe Museode Historia Natural ofthespecimensofColostcthus;tomanyresidentsofnorth-
in Lima. ern Peru who provided shelter, food, andassistancetothe
ThefirstspeciesofColostetliiif recorded from northern field parties; toJesus H. CordovaandVictorRMoralesfor
Peru was "Phyllobatcs"sylvatkuscollectedbyG.K. Noblein courtesies at the Museode Historia Natural in Lima; to B.
1916anddescribedbyBarbourand Noble(i920). Fromthat Anthony LuscombeandRainerSchulteforlogisticsupport;
inauspicious beginning, more than seven decades passed to Cesar Aguilar, Christopher C. Austin, Jesus Ccirdova,
before Rivero(1991)describedColostethus idiomclusandC. AlisonJennings, KennethL. Krysko, MaxA. Nickerson,and
mittcrmeieri from Venceremos on the eastern slope of the Jose P. Rosado for the loan ofspecimens; toStefan Lotters
northern part ofthe Cordillera Central and C. poccilonotits forinformation on, and photosof, a Peruvian species, and
from the Rio Maranon Valley. The principal Peruvian toJuajTManuelGuayasaminforaidwiththeResumenand
researcher on Colostctlnts, Victor R. Morales, described C. thekeyinSpanish.Thismanuscriptbenefited fromcritical
iitcubamhensisandC.argywgasterfromthenorthernCordil- review by Luis A. Coloma, Victor R. Morales, and espe-
leraCentral, and middleRi'o Maranon valley, respectively cially Taran Grant and thorough editing by Linda Trueb,
(Morales 1994; MoralesandSchulte, 1993). Ina revisionof who also illustrated the tadpoles and provided images of
theColostethus triliueatus Group, Morales (2002) named C. preserved specimens; I thank them profusely for their ef-
ornntus from theTarapoto regionat theeasternbaseofthe forts. Collectingandexport permitswereissuedby LuisJ.
Cordillera Central. The range of one Ecuadorian species, CuentoAragon,ArmandoPimental Bustamento,Gonzalo
C. clachyliiftiis, wasextended intotheCordillera de Huan- Bravo Meji'a Munoz, and Jose Purisaca, Direccion General
cabamba in Peru by Duellman and Wild (1993); another ForestalydeFauna, MinisteriodeAgricultura, Lima, Peru.
species described from Ecuador, C. ncxipu^, was reported The research reported herein is partofastudy on the pat-
from Peru by Coloma (1995). Thus, to date, nine species terns of speciation and biogeography ofAndean anurans
ofColostethiis havebeen reported from theAndean region supported by a grant (BSR 8805920) from the National
ofnorthern Peru. Science Foundation (W. E. Duellman, PI).
SciENTiiic Papers, Natl'rai, History Museum. The University of Kansas
MAIERIALSAND METHODS
Specimens in museum collections nre identified by Measurements,definitionsofcolorationand structural
theircataloguenumbers precededby the followingcodes: characters, and numbered characteristics in diagnoses
BMNH = British Museum (Natural History); KU = Natu- follow those of Duellman and Simmons (1988) v\ith the
ral History Museum, University of Kansas; LSUMNS = addition of testes color (Coloma, 1995) and the median
Museum of Natural Sciences, Louisiana State University; lingual process (Grant et al., 1997). Measurements were
MHNSM=MuseodeHistoriaNatural,UniversidadNacio- taken with dial calipers to the nearest 0.1 mm. If sex and
nal Ma\ordeSanMarcos;MCZ=MuseumofComparative reproducti\'econdition werenotevidentexternally (swol-
NHMG
Zoolog)', Harxard University; = Naturhistorika len Finger 111 or vocal sacs in males; eggs visible through
Museet Goteborg; UF = Florida Natural History Mu- body wall in females) sex was determined by dissection.
seum. All specimens from northern Peru and southern Males with granular testes were determined to be adults;
Ecuador that ha\'e been studied are listed in Appenciix 1. females with expanded, convoluted oviducts or large ova
Localities from which specimenshavebeenexamined are were considered to be adults. Throughout, snout-vent
listed with their geographic ctiordinates, elevation, and length is abbreviated SVL, and larval labial tooth row
vegetation type in Appendix 2. Geographic coordinates formulaisabbreviated LTRF.Tadpoleswerestagedaccord-
were obtained from maps, principally the Mapa Fisico ing toGosner's(1960) table;terminology fortadpoleswas
Politico 1:1,000,000 (1973)butalsotheCarta Nacional del based in Altig and McDiarmid (1999). Neuromasts were
Peru, 1:100,000 (1986) for those regions so mapped; the not evident in any of the tadpoles under 20x magnifica-
Institute Geografico Militar, Lima, Peru, produced both tion; therefore, lateral line systems are not included in the
sets of maps. descriptions of tadpoles.
ANDESOF NORTHERN PERU
— mm
The geological history, physiography, climate, and Dry forest. In areas receiving 1000-2000 of rain
vegetation of the northern Andes were described by Du- annualh', this forest develops peripheral to thorn forest
ellman and Pramuk (1999); thus, only a thumbnail sketch and in the rain shadows atelevations of25t)-600 m of the
is presented here. A major orogenic difference between Ri'o Mavo and middle Rfo Huallaga.
—
the northern and southern Andes is the deflection in a Montane dry forest. Isolated patches of this forest
regionofcomplex interdigitationofrelatively low ranges, existatelevationsofprincipally at2000-2500 m in the up-
—
basins, and valleys the Huancabamba Depression en- per Rio Maranon Valle\', in the Cordillera Occidental and
compassing the Ecuador-Peruvian border (Figs. 1 and 2). Cordillera Central. —
In this region, major rivers flow north or south between Humid montane forest. This is the dominant type
intervening north-south highlands. The backbone of the of forest on the lower slopes (up to about 2500 m) of the
Andes in Peru is the Cordillera Occidental, which north Cordillera de Huancabamba and Cordillera Colan.
—
oftheNudode Pasco incentral Peru isseparated from the Very humid montane forest. This is the so-called
Cordillera Central by the valley of the Rfo MarancSn; this cloud forest characteristicofele\'ationsof2500-3000m on
mm
Cordillera has its northern terminus at about 5'S latitude windward slopesoftheAndesthat recei\-e 1000-2000
and is separated from the Cordillera Oriental b\- the \al- ofrainannually. Ihistypeofforestoccursathighelevations
ley of the Rfo Huallaga, which turns eastward and forms of the Cordillera de Huancabamba and Cordillera Colan,
the northern edge of the Cordillera Oriental at about 7 S and the eastern slopes of the Cordillera Central.
—
latitude. Humid subtropical forest. Forest receiving 1000-
mm
Ninetypesofvegetation canbe recognized bysimpli- 3000 of rain annually at elevations of 500-1900 m;
fying the system used by Tosi (1960), as follov\-. this is characteristic of theeastern slopesoftheCordillera
—
Desert scrub. Dr\' Pacific lov\ lands receiving less Central and middle Rio Mayo Valley.
mm —
than 150 of rain annually with legumes and cacti Subtropical pluvial forest. In northern Peru, this
near the western base of the Andes up to as much as typeofforest, which receixes rainfall inexcessof4000 mm
500 m. annually, is known only from the crest (> 3000 m) of the
—
Thorn forest. A forest dominated by legimies, cacti, Cordillera Central west of the Ki'o Mavo.
—
and othiM drought-resistant trees in areas receiving less Humid tropica! forest. TheAmazonian rainforestat
mm m mm
than 500 ofrain annually on the western slopesofthe elevations < 300 receiving rainfall in excessof2000
Cordillera Occidental to about 1200 m and in the interior annualh'; great species diversitx' of trees, some of which
valleys of the rfos Chamaya, Chichipe, Huancabamba, form a ciimplele, or nearly so, canopy 30^0 m above the
Marafion, and Utcubamba. ground.
COLOSTETUVS OV NoRTHKRN PeRU
SUMMARY OF TAXONOMIC CHARACTERS
Compared to their colorful allies (AUobates, Cryp- Table1. Bodysizes(SVLin mm)ofColoslethu^intheAndesofnorthern
topln/llobntes, Dendrobaics, Epipcdobatcs, Miuyobates, and Peru. Values include range (mean, sample size); SexD = sexual dimor-
phism.
Phyllobntes), frogs ofthe genus Coloftethufi are rather drab
in appearance. Living individuals of most species have
distinctive colorations, but individuals that were easily
distinguished in lifecommonlyaredifficulttodistinguish
once they havebeen preserved. Consequently, taxonomic
studiesnecessitatedetailed and comparablediagnosesand
descriptions.
Edwards (1971) made the first attempt to standardize
diagnostic character states in Colofitctliu> bv recognizing
21 features in adults and larvae. Duellman and Simmons
(1988) reduced the nimiberto 15 charactersofadults. This
schemewaspartially followedbyMorales(1994, 2002)and
modifiedslightlybyColoma(1995)withtheadditionoftes-
tescolor;Grantetal. (1997)added the presenceorabsence
ofa median lingual processtothediagnosticcharactersof
Colostethus, and Grant and Castro (1998) and Grant and
Ardila-Robavo(2002)added theso-calledblackarm band,
characteristicoftheColostctliu^ nviio^iGroup. Lottersetal.
(2003) added cloacal tubercles and cloacal sheath to their
diagnosis. Herein, I define 17 diagnostic features.
—
1. Sizeand proportions. Snout-vent length (SVL) is
the straight-line distance from the tip of the snout to the
posterior terminus ofthe b—ody. In making comparisons, 1
use some subjective terms small (< 20 mm), moderately
small (20-25 mm), and moderately large (>25 mm). Head
length is the chord of head length, i.e., the distance from
thetipofthesnouttotheposterioredgeofthearticulation
of the jaw. Head width is the greatest width of the head.
Theeyeandtympanumsizesarehorizontal measurements
ofthe eye and visible part ofthe tympanum, respectively,
and the eye-nostril distance is measured from the ante-
rior corner of the orbit to the posterior edge of the nostril
opening. Tibia length is the distance from the knee to the
distal end ofthe tibia. Foot length is the distance from the
proximal edge of the inner metatarsal tubercle to the tip
ofToe IV.
mm
Snout-vent lengths vary from less than 18.0 in
males of Colostetliiis nrgi/wgastcr, claLht/histiis, iiisulntii^,
mm
and oniatiis to 30.0 or more in C. sordidntiis and C.
si/lvnticus. Thelattertwospeciesand C. ncrugiiiosus and C.
utcubniiibeiisishavethegreatestsexualdimorphism inSVL
(Table 1). Proportions are much the same in all species of
Colostetliiis in northern Peru. The ratio of head length to
SVLisslightlymorethantheratioofhead widthtoSVLin
most species, but the ratios are reversed in C. acriigiiiosits
and are equal in C. iiisiilatiis and C. sordidntiis.
The lengthofthesnout isexpressed as the ratioofthe
eye-nostril distancetothelengthoftheeye. Ratiosareless
than 60% in three short-snouted species (C. elacln/histiis,
ScinN'TiFic Papers. Nati'rai, History Museum, Thh University OF Kansas
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Caiabambai^
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CoiosTFTHis oi- Northern Pkrl!
Scientific Papkrs, Natural History Museum, The University of Kansas
Table2. Statesofstructuralcharactersandcoloration inCd/iisfcf/ms from theAndesofnorthern Peru.
COLOSTETHUS OF NORTHERN PeRU
hind limb; in most species, the stripe is continuous ante- fourspecies—gray throatorabdomen in malesand cream
riorh' along the outer ecige ot the upper eyelid and along or white in females (C. onmtus, fioididatii>, and utcubain-
the canthus rostralis to the tip of the snout. Dorsolateral boisis), or gray with cream spots in some females versus
stripes are present in only six species in the region (C. cream in males (C. einchyhistiis). The males of Colostethiis
dciitlii'ivdactylus, luwipiis, oniatiis, fipiloto^y^a^tci-, $iflvnticiis ivgyiognstL'v are distinctive in having an orange inguinal
and iitciibiiiiibeii^is). The oblique lateral stripe (Character region in life.
—
10) is present on the flank in man\' species; itoriginates in 15. Median lingual process. The presence of a me-
the groin (at about midheight of the insertion of the hind dian lingual process on the dorsal surface of the tongue
limb) and ma\' extend anteriorly tothe midflank regionor was reported in nine species ofColostethus from Chocoan
exen to the posterioredgeofthe uppereyelid. An oblic]ue Ecuaciorand Colombia, GuyananVenezuela, andAmazo-
lateral stripe is absent in C. onintus and C. si/Ivaticiif. The nian Brazil (Grantet al., 1997; Grantand Rodriguez, 2001;
stripe is short and confined to the groin in C. Icucoplmcus Myersand Donnelly, 1997). NospeciesfromPeruisknown
and C. pocciliviotiis; it is diffuse in C. cmspcdoccpf and is to possess this structure.
fragmented in C. clciitlicrodtu'tj/lus and some individuals 16. Swollen fingers in males.—The preaxial part
of C. ;/('.v//'((.s. In some species, a pale ventrolateral stripe Finger III is swollen laterally in males of many species of
h(aC\h'airnagctaedra1r1k) ixs-epnrteesr.enAt;mothnisgisthmeosstpencoiteiscienabtlheeiAnnsdpeecsieosf ClioulconsttuesthGurs,ouepsp(ecMioarlallvesi,n2m00e2m).beFrinsgeorfItIhaelsCoohisstscwtolluilsentriin-
northern Peru, a ventrolateral stripe is present only in C. some males of C. triliiicntus (Grant and Rodriguez, 2001),
argywgastcr and C. oiiiatiis. — and inseveralotherspecies,e.g.,C. iiiguinalis(Grant,2004)
12. Coloration of the gular-chest region. Uniform and C. iiubicoln (Ibaiiezand Smith, 1995). Theonly species
coloration of the gular-chest region characterizes adults withaswollen FingerIII in the regionunderconsideration
of se—ven species of Colostcthus in the Andes of northern is C. onintus, a memberoftheColostcthus triliiicntus Group
Peru cream in C. argyrogastcr, cleutlieyodncti/his, Icucoplm- (sensu Morales, 2002).
t'i/s, lu'xipus, pocciloiiotui': pale gray in C. iitcubaudh'iisis, 17. Testis color.—Coloma (1995) noted that the testes
grayish brown or cream in C. cmspedoceps, and gray or are brown in three species of Colostetluis in Ecuador. All
white in C. onintus. The most common markings in the
male Colostethus examined from Peru have white testes,
gular-chest region are a pair ofdarkbrown to black spots
as do most species in Ecuador.
posterolaterallyonthethroat;thesearepresentinadultsof
In addition to the foregoing characters that are used
C. elnchyhistiis, idioiiicliis, iiifidatiis, iiiittenueicri, andpresent
in the diagnoses of species of Colostethus, other structural
or not in C. sylvnticus. Other color patterns on the gular-
features and aspects of coloration differ interspecifically.
chestregionconsistofcreamspotsonabrownbackground
Structural features include texture of the skin on the dor-
(C. nerugijiosiis and C. piilchcmiutis), many small brown sum, which is smooth in most species, but with minute
spots (C. spilotogastci), or a dark gray intrusion laterally
tubercles posterior to the sacral region in C. neruginosus,
on the throat in C. sordidatiis (may be an incipient pair of nrgywgnster, crnspiedoceps, and idioinelus. The skin on the
dark spots).
— dorsumisfinelyshagreeninC. iiiitteniieieri, sordidntus, and
13. Coloration of abdomen. In life, the entire ab- sylvntieus, and shagreen with minutetuberclesposteriorly
dominal region ispalecream tocreamy yelloworwhite in inC. iiexipusand C. poeeilouotus.Theskinontheflanksusu-
most species ofColoftctlnis in theAndes ofnorthern Peru, ally has more texture (usually shagreen) than that on the
but it is silver in C. nrgi/wgnster and gray or white in C. dorsum; in most species, it is shagreen, but it is smooth in
foididatub.—Other species have distinctive patterns on the C.neruginosus,nrgyrognster,elachyhistus, and uteidmuibensis,
abdomen mottled gray and white anteriorly and yellow anci weakly granular in C. crnspedoceps and C. sordidntus.
posteriorlyonabdomenanci ventral surfacesofhind limbs Distinct tubercles are present below the tympanum in C.
(C. idioincliis and C. sordidatiis), mottled throughout with poeeilouotus. In most species ofColostethus in theAndes of
gray (C. aerugiuosis), gray with white spots (males of C. northern Peru, the cloacal opening is directed posteriorly
utcubambeiifis and some males of C. elncbyhistiis), mottled or posteroventrally at the upper level of the thighs; how-
withgrayanteriorly (C. iiiittcniwicii), orcream withbrown ever, in C. ernspedoeeps and C. nexipus, the cloacal sheathis
mottling (C. piilclicniiiiiis) or spots (C. spdotogastcy). relatively long and the opening is located at the midlevel
—
14. Sexual dimorphism in coloration. As isevident of the thighs and directed \-entrally.
from the character states in Characters 12 and 13, sexual None of the species of Colostethus in the Andes of
dimorphism in coloration of preserveci specimens is evi- northern Peru hassupernumerary tubercles on the digits.
dent in five speciesofColostethub in theAndesofnorthern Subarticular tubercles are always present and usually
Peru. Sexual dimorphism in ventral cokiration occurs in smaller on the toes than on the fingers; these tubercles are
10 Scientific Papers. Natural History Museum, The University of Kansas
small and round in most species, but they are distinctly dorsal surfaces of the hind limbs are tan or pale brown,
subconical on the fingers ofC. clncln/hi^tKs, ek'iitherodacty- usually with two to four dark brov\'n transverse bars on
lus, insulatus, mittermeieri, oniatiis, and si/hmticm. Nuptial each segment; there isonlyonebaron each segment in C.
excrescences were not discernable on any males. oniatiis. Irregulardarkbrown markingsarepresenton the
Inaddition tothecombinationsoflongitudinal stripes dorsal surfaces of the hind limbs in C. cmfpcdoccp^ and C.
and differences in ventral coloration, other featuresofthe spilotogaster, and dark markings are absent on the dorsal
colorpatternarenoteworthy insomespecies. In mostspe- surfaces in C. nr;f\/wgaster. Adistinctive longitudinal dark
ciesofColo^tftlniti, thedorsumofthehead and body isdull brownstripeispresenton theanteriorsurfaceofthe thigh
brownwithdarkerbrowntoblackflecks,spots,orirregular in C.argyrogaster,craspedoceps, andpoecilonotus,andonthe
—
marks,buta fewspecieshavedistinctivecolors dullgreen posteriorsurfaceinC. argyrogaster,craspedoceps, and leuco-
in C. acnigiiio^ii^, reddish brown in C. iu^ulatiis, grayish phaeus. Incontrast,C.poeciloiiotushasa palecream stripeon
browninC.leucophaeus,grayishgreenwithcopperybrown the posteriorsurface; C. insulatus, on theanterior surface;
markings in C. piilcherrimus, and olive brown to coppery C. eleutherodactylus, diagonal pale stripe on the anterior
— —
brown inC. sylvatkus orpatterns V-shaped marksinC. surface. Seven species (C. elachyhistus, idiomelus, leucopha-
idiomelus, X-shapedmarkconnected toa teardrop-shaped eus, or}iatus,poeciloiiotus,sordidatus, andspnlotogaster)have
mark posteriorly in C. oniatus, middorsal brown stripe in longitudinal brownstripeson theupperarms; the markis
C. spilotogn^ter, and chevrons in some C. sylvaticus. The crescent-shaped in C. sordidatus.
IDENTIFICATION OF SPECIES
Key tothe Speciesof Coeostethus i\ northern Peru 8. Oblique lateral stripe absent C. oniatus
1. FingerI<II;toesaboutone-halfwebbed;dorsolateral Oblique lateral stripe present 9
and oblique lateral stripes present C. iie.xipus 9. Dorsolateral stripe present C. utcubambensis
Finger I > II or I = II; webbing and stripes variable2 Dorsolateral stripe absent 10
2. Finger I > II; digital discs expanded 3 1(1. Oblique lateral stripe distinct, extending from orbit
FingersIand IIequal in length;digitaldiscsexpanded to groin C. argyrogaster
or not 11 Oblique lateral stripe diffuse, restricted to groin
3. Lateral fringes present on fingers 4 C. craspedoceps
Lateral fringes absent on fingers 8 1'• Dorsolateral stripe present 12
4. Oblique lateral stripe present 5 Dorsolateral stripe absent 15
Oblique lateral stripe absent 7 12. Digital discs greatly expanded 13
Digital discs not or barely expanded 14
5. Obliquelateralstripepresentonlyingroin;toesabout
one-half webbed C. leucophaeus 13. Oblique lateral stripe present C. eteutlierodacti/lus
Oblique lateral stripe extending from orbit to groin Oblique lateral stripe absent C. spilotogaster
(maybeindistinctanteriorlv);toeswith no morethan |_| Lateral fringes present on fingers C. si/h'aficus
basal webbing 6
Lateral fringes absent on fingers C. idiomelus
6. Toes webbed basally; flanks gray with brown mot-
Oblique lateral stripeonly on posteriorpartofbody;
tling; pair ofdark spots JalcialK' on throat
toes about two-thirds webbed C. sordidatus
C. insulatus
Toes not webbed; flank black with pale llecks or C^biique lateral stripe extending from orbit to groin;
streaks; throat cream with or without brin\n mot- toes no more than one-fourth webbed 16
tling \(x Lateral fringespresenttin fingers;toesatleastwebbed
C. pulcherrimus basalK- C. elachyhistus
7. Toes not webbed C. aerugiuosus lateral fringes absent on fingers; toes not v\'ebbed ..
Toes about one-fourth webbed C. iiiittenneieri C. poecilouotus