Ranitomeya toraro Brown, Caldwell, Twomey, Melo-Sampaio & Souza

Brown, Jason L., Twomey, Evan, Amézquita, Adolfo, Souza, Moisés Barbosa De, Caldwell, Jana- Lee P., Lötters, Stefan, May, Rudolf Von, Melo-Sampaio, Paulo Roberto, Mejía-Vargas, Daniel, Perez-Peña, Pedro, Pepper, Mark, Poelman, Erik H., Sanchez-Rodriguez, Manuel & Summers, Kyle, 2011, A taxonomic revision of the Neotropical poison frog genus Ranitomeya (Amphibia: Dendrobatidae) 3083, Zootaxa 3083 (1), pp. 1-120: 42-47

publication ID

http://doi.org/ 10.11646/zootaxa.3083.1.1

persistent identifier

http://treatment.plazi.org/id/1D338788-9569-1575-C8FC-983E39E7FD5B

treatment provided by

Felipe

scientific name

Ranitomeya toraro Brown, Caldwell, Twomey, Melo-Sampaio & Souza
status

sp. nov.

Ranitomeya toraro Brown, Caldwell, Twomey, Melo-Sampaio & Souza   sp. nov.

Account authors: J.L. Brown, J.P. Caldwell, E. Twomey, P.R. Melo-Sampaio, M.B. Souza

Figures 3 View FIGURE 3 , 4 View FIGURE 4 , 9 View FIGURE 9 , 10 View FIGURE 10 (c-m), 11 (a-g, k), 12, 13, Table 4 – 7

Dendrobates quinquevittatus   (non Steindachner 1864) – Silverstone 1975 (partim): p. 35 [ CAS 85681 View Materials collected by F. Baker and W.M. Mannat “Manaos, Brazil ” 1911]  

Dendrobates ventrimaculatus   sensu lato (non Shreve 1935) – Caldwell & Myers 1990 (partim): p. 18, Fig. 11A View FIGURE 11 [MZUSP 63792 and USNM 266119 collected by A. L. Gardner at Cachoeira Nazaré, Brazil, 9 43’S, 61 55”W, on the Rio Jiparaná (= Rio Machado), 1986 (MZUSP specimen not seen by authors)]; Christmann 2004 (partim): p.21, Figs. on p. 21, 99, 153; Brown et al. 2006 (partim): p. 49, Table 2, Figs. 1, 2e View FIGURE 2 , 4 View FIGURE 4 ; Noonan & Wray 2006 (partim): p. 1012, Table 2, Figs. 2 View FIGURE 2 , 4 View FIGURE 4 , 5 View FIGURE 5 .

Ranitomeya ventrimaculata   sensu lato (non Shreve 1935) – Grant et al. 2006 (partim): p. 171; Twomey & Brown 2008 (partim): p. 129, Fig. 6 View FIGURE 6 ; 2009: p. 58; Souza 2009 (partim): p. 32; Perez-Peña et al. 2010 (partim): p. 18, Fig. 13 View FIGURE 13 .

Ranitomeya sp.   – Lötters et al. 2007: p. 510, Fig. 639; Twomey & Brown 2009: p. 58 as sp. B

Holotype. MPEG 13838 View Materials , an adult male ( Fig. 12 View FIGURE 12 ) collected by J.P. Caldwell (original field number JPC 15713 View Materials ) on 22 December 1998, in Brazil, Amazonas state, municipality of Castanho , at km 12 on road to Autazes (ca. 40 km south of Manaus), 40 m elevation, 3° 30' 52.24" S, 59° 49' 51.13" W. This individual was hopping along a 2 cm horizontal branch about 25 cm above ground in primary forest. GoogleMaps  

Paratypes. All from the state of Amazonas, Brazil ( Fig. 12 View FIGURE 12 )   . OMNH 37438–37442 View Materials , MPEG 13839–13842 View Materials , collected from 20 Dec 1998 to 11 January 1999 by J. P. Caldwell , L. J. Vitt, S. S. Sartorius, A. P. Lima, M. C. Araújo and   T. C. Avila-Pires, same locality as holotype GoogleMaps   . OHMH 36666–36667 and MPEG 13036–13037 View Materials , collected from 10 February–26 March 1997 by J. Caldwell, L. J. Vitt, S. S. Sartorius   , T. C. Avila-Pires and M. C. Araújo, at Scheffer Madeireira on Rio Ituxi , ca. 170 km southwest of Lábrea, 107 m elevation, 8° 28' 45" S, 65° 42' 59" W GoogleMaps   .

Etymology. The species name is in reference to the noun “to ‘raro,” which in the Apurinã language means “frog.” This indigenous Amazonian tribe occupies the center of the range of the new species. The specific epithet is used as a noun in apposition.

Definition and diagnosis. Assigned to the genus Ranitomeya   due to the combination of the following characteristics: Adult SVL 15 – 17.0 mm, dorsal coloration conspicuous, dorsolateral stripes extend to top of thigh, ventrolateral stripes present, brightly colored throat, distinctive pale reticulation on limbs and venter, dorsal skin smooth, finger I greatly reduced and shorter than finger II, finger discs II – IV greatly expanded, disc of finger 1.7 – 2.3 times wider than finger width, thenar tubercle conspicuous, toe discs III – V moderately expanded, toe webbing absent, larval vent tube dextral, adults use arboreal phytotelmata for reproduction and deposit eggs above phytotelm, maxillary and premaxillary teeth absent.

Dorsal body and head black with complete yellow middorsal and dorsolateral stripes, extending from vent to rostrum and extending from upper surface of thighs to orbits, respectively. Limbs and venter black with pale to bright blue reticulation forming round black spots on limbs and irregular spots on venter. Chin yellow with large black paired gular spots and a central spot, irregular in some individuals. Tadpole gray, ovoid, with irregular yellow markings present from early in development.

Ranitomeya toraro   can be distinguished from all other dendrobatids by its distinctive color pattern. Other species with which it could be confused include R. amazonica   , R. defleri   , R. flavovittata   , R. sirensis   (and its junior synonyms R. biolat   and R. lamasi   ), R. uakarii   and R. ventrimaculata   (including its junior synonym R. duellmani   ). Ranitomeya defleri   and R. flavovittata   have highly variable dorsal markings consisting of yellow dots and elongated spots on a black ground color (versus complete middorsal and dorsolateral stripes in R. toraro   ); further, R. defleri   has characteristic large yellow blotches behind the eyes. Ranitomeya flavovittata   typically has a pale conspicuous yellow spot on the upper surface of each thigh (versus absent in R. toraro   ).

Some populations of Ranitomeya sirensis   have complete, broad, yellow middorsal and dorsolateral stripes. Because of these characters, these morphs are similar in appearance to Ranitomeya toraro   ; however, in R. toraro   the stripes are thinner and the middorsal stripe widens anteriorly, becoming at least two times wider on the head (versus equal width in R. sirensis   ). Almost all individuals of R. sirensis   possess a large spot that is the same color as the stripe coloration (typically yellow) in the center of the venter (versus spot absent in R. toraro   ). Ranitomeya variabilis   and R. amazonica   are fairly variable species, but the morphs most similar to R. toraro   have a yellow dorsum with a conspicuous black ‘Y’ that extends from the rump to the eyelids (versus the appearance of two black stripes due to complete medial stripe that extends to vent in R. toraro   ).

In southwest Brazil, the co-occurring R. uakarii   appears to be a Müllerian mimic of R. toraro   , but instead of having bicolored dorsolateral and ventrolateral stripes, all its stripes are completely yellow (see R. uakarii   account for complete discussion). Ranitomeya toraro   can be distinguished from the southern morphs of R. uakarii   by the following characters: absence of a large black spot on the rostrum (versus typically present in R. uakarii   ), absence of a complete labial stripe (versus present in R. uakarii   ), fusing of black nostril spots, creating the appearance of a upside-down ‘U’ on the tip of the snout (versus absent in R. uakarii   ), single pair of large black gular spots (versus typically two smaller pairs in R. uakarii   ), and a middorsal stripe that is two times wider on the head compared to the sacral region (versus constant width in R. uakarii   ).

Measurements (in mm) of holotype. SVL 15.7; FL 6.9; TL 6.7; KK 12.6; FoL 6.7; HaL 4.4; HL 5.0; HW 5.0; BW 5.5; UEW 2.4; IOD 2.0; IND 1.9; TD 0.9; ED 2.0; DET 0.4; L1F 1.6; L2F 2.4; W3D 0.9; W3F 0.4. For paratype measurements see Table 7.

Description of holotype. Head widest at jaw articulation; head slightly narrower than body. Head width equal to head length; head width 31.8% of SVL. Snout acuminate in lateral view, truncate with slight rounding in dorsal view. Naris directed posterolaterally, 1.6 from tip of snout; internarial distance 2.4, 47.2% of head width. Canthus rostralis rounded, loreal region flat. Eye–naris distance 1.4, 70.0% of horizontal eye diameter. Tympanum slightly oval, posterodorsal margin hidden by depressor muscle, tympanum 45.0% of eye diameter. Tongue ovoid, attached anteriorly; median lingual process absent. Teeth absent. Paired vocal slits small, located near jaw articulation.

Body with three parallel stripes; middorsal stripe bifurcates anterior to eyes, dorsolateral stripe extends above the center of the eye to groin; ventrolateral stripe integrates into ventral reticulate pattern. Skin texture smooth on head and most of dorsum, becoming weakly granular on posterior surface of dorsum and on limbs. Ventral surfaces of body and limbs weakly granular, chin nearly smooth. Forelimbs slender, hand relatively large, 27.8% of SVL. Finger I considerably shorter than finger II when fingers appressed; finger III> II> IV> I. Discs on fingers II, III and IV greatly expanded; disc on finger I small, rounded. No webbing or lateral fringes on hand. Width of disc on finger III 2.3 times width of adjacent phalanx. Outer metacarpal tubercle (= palmar tubercle) large, round, unpigmented; inner metacarpal tubercle (= thenar tubercle) oval, located at base of finger I. Unpigmented proximal subarticular tubercles present at bases of fingers II, III and IV; on finger I tubercle is halfway to tip of digit. Smaller, distal subarticular tubercles present only on fingers III and IV, tubercle diffuse on finger IV. Tubercles raised in lateral view. Dorsal scutes present on all digits.

Length of legs moderate; heels of appessed legs reach level of eyes. Femur and tibia nearly equal in length; tibia 97.3% of femur; knee–knee distance 80.1% of SVL. Relative lengths of appressed toes, IV> III> V> II> I. Toe I short with rounded disc; toes II, IV and V with moderately expanded discs. Unpigmented outer metatarsal tubercle round, raised; unpigmented inner metatarsal tubercle oval, located at base of toe I. Unpigmented outer metatarsal tubercle located laterally at base of fifth metatarsal; unpigmented inner metatarsal tubercle located medially near base of toe I. Weakly defined tarsal keel extends from inner metatarsal tubercle for about one-third length of tarsus; tarsal tubercle absent. Two subarticular tubercles present on toes III and V, one on toes I and II. Three subarticular tubercles on Toe IV, the basal tubercle weakly defined. Toes lack webbing and lateral fringes.

Variation. Based on the 14 specimens in the type series, SVL (in mm) of adult males averaged 15.1 ± 0.2 (14.8–15.7; n = 9), adult females 16.4 ± 0.3 (16.2–16.7; n = 2), females thus slightly larger (1.3) larger than males. SVL (in mm) of juvenile females averaged 12.2 ± 0.9 (10.3–13.1; n = 3).

The striping pattern among these 14 specimens was remarkably consistent with only minor deviations. Five of the 14 individuals had a slight break in the middorsal stripe; one of these specimens had three breaks and a horizontal stripe connecting the middorsal and left dorsolateral stripe. Only one specimen had a break in either dorsolateral stripe. Specimens from the Autazes locality (n = 10) differed slightly from the Ituxi specimens (n = 4). Those from the Ituxi locality had breaks in the bifurcation of the middorsal stripe, two with breaks on both sides, and two others with breaks only on the left side. No Autazes specimens had breaks in the bifurcation of the middorsal stripe. The dorsolateral stripes in the Autazes specimens were complete (extended below eye to side of body) in two specimens, including the holotype, broken below the eye on both sides in five specimens, and on one side only in three specimens. All Ituxi specimens had breaks below the eye on both sides. Also see variation in Figs. 10 View FIGURE 10 (c-m) and 11 (a-g, k).

Color in life. Ituxi specimens: ground color of dorsum black with three longitudinal stripes; dorsolateral stripes are iridescent yellow; middorsal stripe light yellow or light blue on back, becoming deep yellow on head. Middorsal stripe bifurcates on head (incomplete in some specimens) and extends anterior to eye not fusing with labial stripe, dorsolateral stripe extends above the center of the eye (in some speciments posterior to eye) to groin, ventrolateral stipe near axilia is light blue or greenish blue, then yellow in groin. Stripe expands on proximal upper arm to form a triangular light yellow spot. Small yellow rostral spot on tip of snout. Arms, legs and ventral surfaces with blue reticulate pattern on black ground color, forming large black round or elongate spots. Iris black. Specimens from Autazes similar, although some specimens have a light yellow reticulate pattern on the legs and venter.

Color in preservative. Dorsum dark gray with three whitish but distinct longitudinal stripes on body and head. Middorsal stripe bifurcates on head anterior to eye and extends below eye alongside to groin. Large central whitish spot on tip of snout. Reticulate pattern distinct, in shades of gray, on upper limbs, sides and all ventral surfaces except chin. Chin with central irregular whitish spot that connects to reticulate pattern on chest.

Tadpole. Five back-riding tadpoles were available for description. Three were taken from OMNH 36667 on 13 February and two were taken from MPEG 13037 on 26 March. Both nurse frogs were males and taken from the same locality; therefore, the five tadpoles are described together. All measurements (mm) are means ± SE (range in parentheses).

All tadpoles in stage 25; no external gills, not yet feeding, intestine with some yolk remaining. Snout rounded in dorsal and lateral profile; body depressed. Total length 9.5 ± 0.07 (9.3–9.6); body length 3.4 ± 0.04 (3.2–3.5); tail length 6.1 ± 0.05, 64.2% of total length. Body width 2.5 ± 0.1 (2.1–2.6); body depth 1.8 ± 0.09 (1.6–2.1); body depth 72% of body width. Eye well developed; naris small; distance from naris to anterior edge of eye 0.4 ± 0.02 (0.3–0.5). Eye positioned dorsally on head, directed dorsolaterally. Spiracle sinistral; vent tube dextral.

Tip of tail bluntly rounded. Tail muscle height at base of tail 0.9 ± 0.04 (0.8–1.0); tail muscle width at base of tail 0.9 ± 0.03 (0.8–1.0); maximum tail height 1.4 ± 0.03 (1.3–1.5). Dorsal fin slightly higher than ventral fin.

Oral disc ventral, emarginate; transverse width 0.9 ± 0.02 (0.8–0.9), 36% of body width. Single row of small papillae present laterally and ventrally; dorsal gap where papillae absent. The three tadpoles from OMNH 36667 have only A-1 developed on upper labium; P-1 on lower labium with narrow medial gap; P-2 short. The two tadpoles from MPEG 13037 have A-2 developed in addition to A-1. A-2 composed of two small segments with a large medial gap. LTRF for latter two tadpoles 2(2)/2(1), additional posterior row may develop in older tadpoles.

Color in preservative. Dorsum light yellow-brown with minute brown flecks. Skin opaque, gut reddishbrown. Tail musculature yellow-brown with tiny brown evenly spaced flecks; tail fins transparent with tiny brown evenly spaced flecks.

Vocalizations. Unknown.

Distribution and natural history. Ranitomeya toraro   occurs in southwestern Brazil and the southeastern tip of Colombia, where it is known from 12 localities ( Fig. 13 View FIGURE 13 ; genetic data are from three localities). This species has been observed in the Brazilian states of Amazonas, Acre and Rondônia and the Colombian department of Amazonas. It likely occurs widely throughout the Madeira, upper Juruá and upper Purus river drainages, although further sampling is needed to determine the extent of its distribution.

Individuals from all localities have been found in undisturbed “terra firme” primary forest or old-growth secondary forest in Amazonia. These forests are not subject to flooding during the rainy season. At three localities (Boca do Acre, Autazes, Ituxi), undisturbed forests were characterized by large rainforest trees, such as Brazil nut trees ( Bertholletia excelsa   ). Canopy height varied from 20 to 35 meters. The understory was open to relatively dense.

These frogs were relatively uncommon at all sites surveyed. At the Rio Ituxi site, only five frogs were observed in two months of fieldwork. Eleven individuals were found in 24 days at the Autazes site, and nine individuals were found in six days at the Boca do Acre site. At the Rio Ituxi site, frogs were found only in terra firme forest, even though extensive work was done in flooded forests along the river. Of the five frogs observed, two were in leaf litter and three were an average of 35 cm above ground on a leaf, a fallen branch and a log. At the Autazes site, two frogs were found in undisturbed primary forest and nine were found in old second-growth forest. Three were in leaf litter and eight were above ground (average, 80 cm) on leaves (two), logs (three), Heliconia   leaves (two) and a dead palm frond (one).

To date, tadpole development sites have been found only at the Boca do Acre site. Forests at the Autazes and Ituxi sites had relatively few obvious types of phytotelmata that could serve as tadpole habitats, although Heliconia   stands were present at the Autazes site. Four frogs found transporting tadpoles on their backs had one, two, three and three tadpoles, suggesting that males frequently carry more than one tadpole at a time. Two egg clutches were found at the Boca do Acre site, one with two eggs 5 cm about the waterline of a bromeliad, Aechmea cf. bromeliifolia   and another with a single egg in the axil of the bananeira-brava plant ( Strelitziaceae   : Phenakospermum guyanense   ). Five tadpoles were found in bromeliad tanks and 20 were found in axils of P. guyanense   ; these tadpoles were always found occurring in separate tanks or axils, indicating that cannibalism may occur.

Notes. Unlike many species of Ranitomeya   , R. toraro   displays remarkably little morphological variation across its expansive geographic range. Although this species is sister to R. defleri   , the two species display distinct morphological differences and deep genetic divergence. These differences are maintained even when examining R. toraro   from Leticia, CO, which is the site where the two species come in closest contact (to our knowledge). Thus, it is unlikely that the morphological and genetic differences we observe between the two species are products of isolation-by-distance.

Conservation status. Following the IUCN Red List categories and criteria ( IUCN 2010), we tentatively suggest listing this species as Least Concern (LC). The total geographic extent of this species exceeds 800,000 km 2 and much of the forests in the Madeira, upper Juruá and upper Purus drainages remain intact. However, given dramatic deforestation rates in Brazil, significant habitat loss in the near future could endanger this species.

CAS

California Academy of Sciences

T

Tavera, Department of Geology and Geophysics

Kingdom

Animalia

Phylum

Chordata

Class

Amphibia

Order

Anura

Family

Dendrobatidae

Genus

Ranitomeya

Loc

Ranitomeya toraro Brown, Caldwell, Twomey, Melo-Sampaio & Souza

Brown, Jason L., Twomey, Evan, Amézquita, Adolfo, Souza, Moisés Barbosa De, Caldwell, Jana- Lee P., Lötters, Stefan, May, Rudolf Von, Melo-Sampaio, Paulo Roberto, Mejía-Vargas, Daniel, Perez-Peña, Pedro, Pepper, Mark, Poelman, Erik H., Sanchez-Rodriguez, Manuel & Summers, Kyle 2011
2011
Loc

Ranitomeya sp.

Twomey, E. & Brown, J. L. 2009: 58
Lotters, S. & Jungfer, K. - H. & Schmidt, W. & Henkel, F. W. 2007: 510
2007