Research Article |
Corresponding author: Carolina Reyes-Puig ( carolina_reyes.88@hotmail.com ) Academic editor: Angelica Crottini
© 2019 Carolina Reyes-Puig, Juan Pablo Reyes-Puig, Daniel A. Velarde-Garcéz, Nicolás Dávalos, Emilio Mancero, María José Navarrete, Mario H. Yánez-Muñoz, Diego F. Cisneros-Heredia, Santiago R. Ron.
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Citation:
Reyes-Puig C, Reyes-Puig JP, Velarde-Garcéz DA, Dávalos N, Mancero E, Navarrete MJ, Yánez-Muñoz MH, Cisneros-Heredia DF, Ron SR (2019) A new species of terrestrial frog Pristimantis (Strabomantidae) from the upper basin of the Pastaza River, Ecuador. ZooKeys 832: 113-133. https://doi.org/10.3897/zookeys.832.30874
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We describe a new species of Pristimantis from the montane forest of the Río Zuñag Ecological Reserve, upper basin of the Pastaza River, Ecuador. Pristimantis mallii sp. n. is characterized by a snout-vent length of 11.6–21.3 mm in adult males (n = 12), 22.6–34.3 mm in adult females (n = 8), and is compared morphologically and genetically with Pristimantis miktos and with other relevant species of Pristimantis. The new species is characterized by having skin on dorsum and flanks shagreen, distinctive scapular folds, snout broadly rounded in dorsal view, upper eyelid bearing one or two subconical tubercles and some rounded tubercles, dorsum and flanks light brown to brown, with irregular dark brown marks bounded by dirty cream and groin with irregular yellowish marks.
Describimos una nueva especie de Pristimantis del bosque montano de la Reserva Ecológica Río Zuñag, cuenca alta del río Pastaza, Ecuador. Pristimantis mallii sp. n es caracterizada por una longitud rostro-cloacal de 11.6–21.3 mm en machos adultos (n = 12), 22.6–34.3 mm en hembras adultas (n = 8), y es comparada morfológica y genéticamente con Pristimantis miktos y con otras especies relevantes de Pristimantis. La especie nueva se caracteriza por tener la piel del dorso y flancos finamente granular, pliegues escapulares distintivos, hocico redondeado en vista dorsal, párpado superior con uno dos tubérculos subcónicos y algunos redondeados, dorso y flancos café claro a café, con marcas irregulares café oscuras bordeadas de crema sucio y marcas irregulares amarillentas en las ingles.
Montane forest, Pristimantis mallii sp. n., Río Zuñag Reserve, Terrarana
Bosque montano, Pristimantis mallii sp. n., Reserva Río Zuñag, Terrarana
The genus Pristimantis is an endemic group of terrestrial frogs of the Neotropical region; with more than 525 species, it is the largest genus of all vertebrates (
The upper basin of the Pastaza River is an important endemic region, mainly because the Río Pastaza is a major Ecuadorian tributary of the Amazon (i.e. biogeographic barrier), with a rugged topography of volcanic and granitic origin (
DNA extraction and amplification processes took place at the Laboratorio de Biología Molecular of the Museo de Zoología, Pontificia Universidad Católica del Ecuador (
The sequences generated de novo were assembled and edited manually on the GeneiousPro 5.4.6 software (Biomatters Ltd). Both ends of the sequence were cut during editing to avoid low quality base pairs. GenBank Access codes were assigned to new sequences presented in this study are MK391384, RAG1; MK391386, 16S, tRNAs, ND1 for
New sequences were compared to the GenBank sequences using the BLAST tool (http://blast.ncbi.nlm.nih.gov/Blast.cgi) in order to confirm their genetic identity and determine similar species that allow the evaluation of the phylogenetic position of the new taxon. The search showed a high likeness between the new species and Pristimantis riveti. Therefore, we have included comparisons with P. riveti and other closely related species (sensu
Multiple sequence alignment was done on the GeneiousPro 5.4.6 software under the MUSCLE algorithm (
Phylogenetic trees were rebuilt based on Bayesian inference and maximum likelihood estimation (MLE). For the MLE analyses, 4 independent searches of one replica each were performed, two of them under the systematized starting command stepwise (streefname = stepwise) and the remaining two were configured under the alternative command random (streefname = random). Phylogenetic searches ended after 2000000 degenerations with no improvement in the tree’s topology (genthreshfortopoterm = 2000000). The support of each branch was estimated considering 200 bootstrap replicas obtained under the same configuration parameters used to determine the best tree. The consensus tree was estimated in the Mesquite v2.75 software by a 50% majority consensus rule. Bayesian inference analyses took place on the Mrbayes v3.2 software (
Description, measurements and terminology follow the standardized format of
Placement of Pristimantis mallii sp. n. in the genus Pristimantis was strongly supported, and according to the available information, the new species is sister to Pristimantis miktos. Both species form a clade with high support (Fig.
Phylogeny of Pristimantis showing the relationships of Pristimantis mallii sp. n. (red). The phylogram was derived from analysis of 2968 bp of mitochondrial (gene fragments 12S and 16S) and nuclear (gene fragment RAG) DNA sequences. Branch support is presented for each clade as Bayesian posterior probabilities × 100 (left of the slash) and non-parametric bootstrap (right of the slash). Asterisks indicate support values of 100. The external group is not shown. For each specimen, museum catalog number, locality, and GenBank accession number (in parentheses) are reported. Abbreviations: E. R. = Ecological Reserve.
(7 females, 12 males).
We assign the new species in Pristimantis based on our molecular data (Fig.
A new species of Pristimantis having the following combination of characters: (1) skin on dorsum and flanks shagreen, with rounded tubercles scattered towards the axillary region, with “) (” shaped scapular folds (evident in life); dorsolateral folds absent; skin on venter areolate; discoidal fold slightly defined; (2) tympanic membrane and tympanic annulus present, round, equivalent to 45% of ED; supratympanic fold present; (3) snout broadly rounded in dorsal view, moderate in length and rounded in lateral view; (4) upper eyelid with one or two subconical tubercles on the center of eyelid and some rounded tubercles (less evident in preserved specimens); EW 100% of IOD; cranial crests absent (5) dentigerous processes of vomers oblique in outline, with five to seven teeth, moderately separated, posteromedial to choanae; (6) vocals slits and nuptial pads present; (7) Finger I shorter that Finger II; discs of digits expanded, truncate; two times the width of the digits on Fingers III and IV; (8) fingers with lateral fringes; (9) ulnar tubercles present, rounded; (10) heel bearing one or two subconical tubercles (less evident in preserved specimens) surrounded by few lower rounded tubercles; inner tarsal fold present, it extends up to 1/4 of the tarsus; (11) inner metatarsal tubercle oval, 5–6× as large as outer metatarsal tubercle that is subconical; supernumerary plantar tubercles indistinct; (12) toes with slightly defined lateral fringes; webbing absent; Toe V longer that Toe III, disc on Toe V reach the distal subarticular tubercle on Toe IV; (13) in life, dorsum and flanks light brown to brown, with irregular dark brown marks bounded by dirty cream, light brown or greenish cream; hidden surfaces of thighs brown splashed with dirty cream; groin with irregular yellowish marks; venter light gray or cream, spotted to densely spotted with brown. Golden coppery iris with black reticulations and a reddish-brown horizontal stripe; (14) SVL in adult males 16.7 ± 4.5 (11.6–21.3 mm); females with 27.6 ± 3.9 (22.6–34.3).
Pristimantis mallii is most similar to its sister species P. miktos (
Other species of Pristimantis from the eastern lowlands of Ecuador, that can be confused with the new species by having dermal ridges in the scapular region, are P. kichwarum (
Adult female. Measurements (in mm): SVL 28.7; tibia length 15.6; foot length 15.2; head length 11.7; head width 12.8; eye diameter 4.7; tympanum diameter 2.5; interorbital distance 3.6; upper eyelid width 3.7; internarial distance 3.5; eye–nostril distance 4.6. Head slightly wider than long (12.8 mm vs 11.7); head width 44.4% of SVL; head length 41% of SVL; snout broadly rounded in dorsal view, moderate in length and rounded in lateral view (Fig.
Skin on dorsum and flanks shagreen, with rounded tubercles scattered towards the axillary region, with “) (” shaped scapular folds (evident in life); dorsolateral folds absent; skin on venter areolate; discoidal fold slightly defined; cloaca with rounded tubercles on the inferoposterior margin. Forearms slender, ulnar tubercles present, rounded; palmar tubercle heart-shaped, bilobed, approximately twice the size of oval thenar tubercle (the tubercles are slightly defined); subarticular tubercles rounded, defined, few supernumerary tubercles, indistinct; fingers with narrow lateral fringes; Finger I shorter than Finger II; disc on Finger I rounded and on Finger II expanded, twice the width of the digits on Fingers III and IV, truncate; pads on fingers well defined by circumferential grooves on all fingers (Fig.
Hindlimbs slender, tibia length 54% of SVL; foot length 53% of SVL heel; upper surfaces of hindlimbs shagreen; posterior surfaces of thighs smooth, ventral surfaces areolate; heel bearing one or two subconical tubercles (less evident by preservation effect) surrounded by few lower rounded tubercles; inner tarsal fold present, it extends up to 1/4 of the tarsus; inner metatarsal tubercle oval, 5–6× as large as outer metatarsal tubercle that is subconical; supernumerary plantar tubercles indistinct; toes with slightly defined lateral fringes; webbing absent; discs on Fingers I and II rounded, discs in Fingers III, IV and V expanded, twice the width of the digit; all toes with ventral pads well defined by circumferential grooves; Toe V longer that Toe III, disc on Toe V reach the distal subarticular tubercle on Toe IV (Fig.
(based on digital photographs, Fig.
Coloration in life of Pristimantis mallii sp. n. Dorsal view. A
(Fig.
Preserved individuals (Figs
Preserved individuals of Pristimantis mallii sp. n. showing dorsal and ventral variation in adult females A–G dorsal view H–N ventral view. A, H
Preserved individuals of Pristimantis mallii sp. n. showing dorsal and ventral variation in males A–G dorsal view H–N ventral view. A, H
Measurements (in mm) of type series of Pristimantis mallii sp. n. Ranges followed by mean and standard deviation in parentheses.
Characters | Females (n = 8) | Males (n = 12) |
---|---|---|
SVL | 22.6–34.3 (27.6±3.9) | 10.2–21.3 (16.7±4.5) |
TL | 13.1–16.0 (15.3±1.0) | 8.8–11.4 (10.7±1.0) |
FL | 12.2–15.0 (14.3±1.2) | 8.2–11.4 (9.6±1.1) |
HW | 9.4–14 (11.8±1.4) | 5.8–8.9 (7.4±0.9) |
HL | 9.5–14.2 (12.1±1.4) | 6.2–8.2 (8.1±0.9) |
IOD | 2.7–4.2 (3.6±0.4) | 1.7–2.8 (2.3±0.3) |
EW | 3.0–4.0 (3.5±0.3) | 1.9–3.2 (2.6±0.3) |
IND | 1.8–3.7 (3.1±0.6) | 1.1–2.9 (2.1±0.5) |
EN | 3.1–4.6 (4.0±0.5) | 2.0–2.8 (2.4±0.2) |
TD | 1.5–3.0 (2.1±0.5) | 1.0–1.7 (1.2±0.2) |
ED | 3.6–5.0 (4.4±0.5) | 2.7–4.1 (3.4±0.4) |
(based on digital photographs of the type specimens, Fig.
Dorsum and flanks light brown (
Pristimantis mallii is only known from Fundación EcoMinga’s Río Zuñag Ecological Reserve, which is located in the southeastern buffer zone of the Llanganates National Park, in Baños, Río Negro, Tungurahua province, in the upper basin of the Pastaza River, on the east-central slope of the Andes in Ecuador. This locality comprises montane cloud forest (
All specimens were found on herbaceous and shrub vegetation inside mature forest, where they perched on herbs, shrubs, palms, ferns, bromeliads and Araceae between 100 and 450 cm above the ground. A couple in amplexus was found in January 2012, and the female deposited an egg clutch in a field bag, in the time passed between being collected in the field and reaching the base camp. Additionally, two couples in amplexus and an adult female were found in October 2017.
The new species is named in honor of the late Dr V. N. Mallikarjuna “Malli” Rao, of Wilmington, Delaware, USA. A winner of the Lavosier Medal at DuPont, he helped develop an environmentally safe alternative to the fluorocarbons that were depleting the ozone layer. His donation to EcoMinga in 2007 started the Río Zuñag Reserve, the type locality of P. mallii.
Pristimantis mallii is part of a clade of Pristimantis distributed in the Andes of central and southern Ecuador. The only non-Andean species of the group is P. miktos, which occurs in the Amazon basin below 300 m. We refrain from assigning the new species to a named species group. Most species groups in Pristimantis have been shown to be non-monophyletic, especially the large P. unistrigatus group (sensu
The upper basin of the Pastaza River has proven to be a priority area for the conservation of Pristimantis due to its high alpha and beta diversity and high endemism (
We thank to Fernando Ayala, Diego Paucar, Yerka Sagredo, Fausto Recalde, Luis Recalde, Santiago Recalde, Diego Páez, Josué Picho, Jackie Álvarez, Claudia Herrera, Carlos Guarderas, Christian Puertas, Ayla Hickey, Benjamín Arias, Guillem Rius, and Javier Robayo for their field assistance. EcoMinga Foundation would like to thank Henri Botter, Ardy van Ooij, IUCN-Netherlands and Netherlands Postcode Lottery for financing surveys and support assistance of the Rio Zuñag Reserve, and World Land Trust, Rainforest Trust, Orchid Conservation Alliance, Vera Lee, and the late Malli Rao for supporting our land purchases in this area. We also thank to World Wildlife Fund (WWF) for their support to field researches and the consolidation of protected areas. Field work of the INABIO had the support of Miguel Urgilés, Diego Inclán and Francisco Prieto. Ministerio del Ambiente issued collection permits No. 0018-09icfaudnb/MA, 001-018-FAU-DNBAPVS/MA, Nº 18-2017-IC-FAU-DNB/MAE. Field and laboratory work by
Additional specimens examined
Pristimantis kichwarum: Ecuador, Orellana: