A new giant Pristimantis (Anura, Craugastoridae) from the paramos of the Podocarpus National Park, southern Ecuador

Abstract A new species of frog of the genus Pristimantis is described from the paramos of the Nudo de Cajanuma, Podocarpus National Park, on the border between the provinces of Loja and Zamora-Chinchipe, Ecuador. The new species is readily distinguished from all other species of Pristimantis by its large body size (snout-vent length: 50.0–50.5 mm in adult females, 34.7–42.5 mm in adult males), thick glandular skin, large warts on flanks, prominent glandular patches on head and legs, and dark brown dorsum. This new species is among the largest and stoutest Pristimantis frogs of the high Andes. It is only known from its type locality, where it occurs in paramo bambusoid meadows at elevations between 3300 and 3400 m. It is morphologically similar to Pristimantiserythros, P.farisorum, P.obmutescens, P.orcesi, P.racemus, P.simoterus, P.simoteriscus, and P.thymelensis. Notorious morphological characters present in this new species are thick glandular patches covering dorsum and limbs and porous skin texture, which are shared with P.erythros.


Introduction
Pristimantis (Jiménez de la Espada 1870) is the most diverse amphibian genus, representing nearly 8% (532 spp.) of all named anuran species worldwide (Frost 2019). Endemic to tropical America, Pristimantis is distributed from Honduras to Argentina, and is the most-species rich genus in anuran communities of the tropical Andes, from Colombia to Bolivia. Frogs of the genus Pristimantis show vast morphological and ecological diversity, which is associated with a complex and challenging taxonomy (Duellman and Lehr 2009, Pinto-Sánchez et al. 2012, Padial et al. 2014. Ecuador holds 39% of all Pristimantis species (210 spp., Ron et al. 2019), but its diversity is still underestimated, and 61 species have been discovered and scientifically described in the country during the last decade . Pristimantis from the Andes of southern Ecuador are little known; with new species frequently discovered, new distributional records revealed, collections of putatively new species deposited in museum collections, and several areas unexplored (Bustamante and Mendelson III 2008, Cisneros-Heredia et al. 2009, 2012, 2016, 2016, 2016, Camacho-Badani et al. 2012, Brito and Pozo-Zamora 2013, Urgilés et al. 2014, Brito et al. 2017, Urgiles et al. 2017, Sánchez-Nivicela et al. 2018, Reyes-Puig et al. 2019. The Podocarpus National Park is located on the southernmost portion of the Cordillera Oriental of the Andes, in the provinces of Loja and Zamora-Chinchipe, southern Ecuador. It protects about 1450 km 2 from 900 to 3600 m elevation, including foothill, low montane, cloud, high montane forests and paramos (MAE 2017). Little information exists about the herpetofauna of the highlands of Podocarpus National Park. Between 2009 and 2010, herpetological surveys were conducted on the paramos of Cajanuma, western side of the Podocarpus National Park, from 3320 to 3365 m elevation, as part of a project to evaluate the impacts of climate change on the biodiversity of this ecosystem Veintimilla-Yánez 2010, L Aguirre Mendoza et al. 2015). During these surveys, three putatively new species of Pristimantis were collected. Herein, we are pleased to describe and name one of these species.

Materials and methods
Field work was carried out between December 2009 and April 2010 in the paramos of the Nudo de Cajanuma (nudo is the local name for transverse mountain ranges), Podocarpus National Park, on the border between the provinces of Loja and Zamora-Chinchipe, Ecuador. Paramos are highland Neotropical ecosystems dominated by grasses and forbs and located between the forest upper limit and the permanent snow line in the Andes from Venezuela to northern Peru (Acosta-Solís 1984, Luteyn 1999. While most paramos occur above 3400 m elevation, in southern Ecuador paramos are found from 2080 m elevation due to local climate and geology (Neill 1999, León-Yánez 2011. The physiography of the paramo of Cajanuma is characterised by series of hills with steep slopes, connected by ridges, and dissected by small streams. While paramos in the Podocarpus National Park typically receive an average annual precipitation < 5000 mm, the paramo of Cajanuma is wetter and may receive up to 6000 mm. During most of the year, local weather is characterized by persistent cloud cover, fierce easterly winds, and low temperatures (maximum daily temperature ≈ 10° C, minimum typically between 0-3 °C), although a short dry season may occur during November and December (Keating 1999, 2008, Lozano et al. 2009. Vegetation is characterised by a diverse physiognomy of grasses, forbs, shrubs, and treelets. Descriptions of the flora of the paramo of Cajanuma were provided by Keating (1999Keating ( , 2008 and Eguiguren et al. (2015).
Description format, definitions and terminology follows standards proposed by Lynch and Duellman (1997) and Duellman and Lehr (2009). For skin texture, we include a new descriptor: porous skin, which is defined by showing small pores evenly distributed across the skin. Areolate, pustulate and shagreen skin textures differ from porous skin by having dermal modifications (granules, protuberances) raised from the background plane of the skin, while the pores of porous skin are below the background plane ( Fig. 1; compare with Duellman and Lehr 2009: fig. 39). Sex and age were determined by direct inspection of gonads. The following measurements were taken with digital calipers to the nearest 0.01 mm and rounded to the nearest 0.1 mm by a single person (David Veintimilla-Yánez): snout-vent length (SVL), straight distance from tip of snout to vent; head width, at angle of jaws; head length, from angle of jaw to tip of snout; eye diameter, horizontally from anterior to posterior corner of eye; interorbital distance, shortest distance between orbits; internarial distance, shortest distance between nostrils; eye-nostril distance, straight distance between anterior corner of eye and posterior margin of nostril; tympanum diameter, greatest horizontal width of tympanum; tibia length, distance from outer border of flexed knee to heel inflection; hand length, distance from base of tenar tubercle to tip of Finger III; and foot length, distance from base of inner metatarsal tubercle to tip of Toe IV. Fingers and toes are numbered preaxially to postaxially from I to IV and I to V, respectively. Comparative lengths of Toes III and V were determined by adpressing both against Toe IV; lengths of Fingers I and II were compared when adpressed against each other. Photographs and field notes were used for descriptions of colouration in life.
Examined specimens are deposited at: División de Herpetología, Instituto Nacional de Biodiversidad, Quito (DHMECN); Instituto de Ciencias Naturales, Universidad Nacional de Colombia, Bogotá (ICN); Laboratorio de Herpetología, Universidad del Valle, Cali (UVC), and Museo de Zoología, Universidad San Francisco de Quito (ZSFQ). Information on species for comparative diagnoses was obtained from examined specimens and literature, including original species descriptions. The following specimens were examined for comparisons: ECUADOR: Vocalizations were recorded with an Olympus WS-750 digital recorder and a Senheiser K6-C unidirectional microphone. During the recordings, air temperature and relative humidity were measured with a Springfield environmental thermometer. Acoustic analyses were done with Adobe Audition 3.0 software package (Adobe Systems Inc., San Jose, California, USA), at a sampling frequency of 44.1 kHz and 16-bit resolution. Waveform and spectrogram were made using Raven Pro 1.4 software package (Cornell Lab of Ornithology, Ithaca, NY) and analysed with a Fast Fourier Transformation of 512 points. Terminology and definitions follow proposals by Duellman and Pyles (1983), Cocroft and Ryan (1995), Díaz and Cádiz (2006), and the following variables were measured: (1) dominant frequency of the call, (2) dominant frequency of the first note, (3) dominant frequency of the second note, (4) calls per minute, (5) notes per call, (6) call duration, (7) note duration, (8) interval between calls, and (9) intervals between notes within a call.  Diagnosis. A new species of Pristimantis diagnosed by the following combination of characters: (1) Skin on dorsum porous, thick and glandular, with large, flat, glandular warts on flanks; dorsolateral folds absent; thick glandular patch on supra/postympanic region, and on dorsal surfaces of humeral, femoral, tibial and tarsal regions; glandular folds in wrists; skin on venter areolate; discoidal fold weakly defined; (2) tympanic membrane and tympanic annulus prominent; tympanic annulus rounded, 36% of eye length, with posterior margin in contact with supratympatic glandular patch; (3) snout rounded in dorsal view; rounded to slightly protruding in lateral view; (4) upper eyelid without tubercles, IOD wider than upper eyelid; cranial crests absent; (5) dentigerous processes of vomers present, oblique, moderately separated, posteromedial to choanae, with 4 to 5 teeth; (6) males with cream-coloured nuptial pads on dorsum of Finger I and vocal slits; (7) Finger I shorter than Finger II; emarginated discs of fingers broadly expanded and elliptical; (8) fingers without lateral fringes; (9) ulnar tubercle present but low or poorly differentiated; (10) heels without tubercles, inner tarsal wart low and poorly differentiated; (11) inner metatarsal tubercle ovoid, about 5-6x the size of subconical, rounded outer metatarsal tubercle; supernumerary plantar tubercles present; (12) toes with narrow lateral fringes; basal toe webbing between toes II-V; Toe V longer than Toe III (disc of Toe III does not reach distal subarticular tubercle on Toe IV, disc on Toe V reaches middle of distal subarticular tubercle on Toe IV); toe discs elliptical, slightly narrower than those on fingers; (13) in life, dorsal surfaces dark brown, chocolate brown, or orange-brown, with or without dark irregular botches, distinctive head markings absent, ventral surfaces brown with irregular pale flecks and blotches, iris bronze with dense black reticulations; in preservative, brown surfaces turn grey; (14) SVL 50.0-50.5 mm in adult females (n = 2), 34.7-42.5 (38.5 ± 2.1 SD, n = 10) mm in adult males (Table 1).

Pristimantis andinogigas
Comparisons. Pristimantis andinogigas sp. nov. is readily distinguished from all other species of Pristimantis by its large body size, thick and glandular skin, large warts on flanks, prominent macroglandular patches on head and legs, and dark brown dorsum. The only species showing a similar combination of characters is Pristimantis erythros Sánchez-Nivicela, Celi-Piedra, Posse-Sarmiento, Urgiles, Yánez-Muñoz & Cisneros-Heredía, 2019, which is readily differentiated from P. andinogigas sp. nov. by being smaller (38.8-42.6 mm in adult females), having a conspicuous red coloration, and lacking dentigerous processes of vomers. In addition, P. andinogigas sp. nov. resembles the following species by bearing large, flat, glandular warts on flanks, and expanded discs on fingers and toes: Pristimantis farisorum Mueses-Cisneros, Perdomo-Castillo, & Cepeda-Quilindo, 2013, P. obmutescens (Lynch, 1980), P. orcesi (Lynch, 1972), P. racemus (Lynch, 1980), P. simoterus (Lynch, 1980), P. simoteriscus (Lynch), and P. thymelensis (Lynch, 1972). Pristimantis andinogigas sp. nov. is larger than any of these seven species, and furthermore, they differ from P. andinogigas as follows (characters of P. andinogigas sp. nov. in parentheses): areolate or shagreen dorsal skin (porous), thin supratympanic folds (prominent supra/post-tympanic glandular patch), thin glandular patches on legs (thick), and smaller body size, with adult females having 38.4-42.3 mm SVL in P. farisorum, 28.5-38.4 mm SVL in P. obmutescens, 35.2-36.1 mm SVL in P. orcesi, 29.9-37.9 mm SVL in P. racemus, 32.4-37.1 mm SVL in P. simoterus, 25.7-31.4 mm SVL in P. simoteriscus, and 28.0-33.5 mm SVL in P. thymelensis (versus 50.0-50.5 mm SVL in adult females of P. andinogigas). In addition, P. farisorum has snout subacuminate in dorsal view (rounded), fingers with narrow lateral fringes (absent), dorsum dark brown to black with irregular and elongated orange marking (brown with or without lighter irregular blotches), and inhabits upper montane forests on the Nudo de Pasto, Andes of southern Colombia (Mueses- Cisneros et al. 2013). Pristimantis obmutescens has tympanum concealed beneath skin (visible), fingers with lateral fringes present (absent), small, non-conical tubercles on heel and outer edge of tarsus present (absent), lacks vocal sac and vocal slits in males (present), and inhabits on the Páramo de Puracé, Cordillera Central of the Andes in southern Colombia (Lynch 1980, Lynch et al. 1996. Pristimantis orcesi has skin on head smooth (porous), fingers bearing lateral fringes (absent), lacks dentigerous processses of vomers (present), and inhabits paramos on the Andes of north-central Ecuador (Lynch 1972(Lynch , 1981. Pristimantis racemus has fingers with lateral fringes (absent), dorsum reddish-brown with darker marking (brown with or without darker irregular blotches), lacks vocal sac and vocal slits in males (present), and inhabits paramos on the Cordillera Central of the Andes, central Colombia (Lynch 1980, Lynch et al. 1996. Pristimantis simoterus has fingers with lateral fringes (absent) and inhabits upper montane forests and paramos on the Cordillera Central of the Andes, central Colombia (Lynch 1980, Lynch et al. 1996. Pristimantis simoteriscus has subacuminate snout in dorsal view, fingers with lateral fringes (absent), dorsum grey with dark markings (brown with or without darker irregular blotches), lacks vocal slits in males, and inhabits paramos on the Cordillera Central of the Andes, central Colombia (Lynch et al. 1996). Pristimantis thymelensis has tympanum concealed beneath skin (visible), paraventral folds present (absent), finger bearing lateral fringes (absent), grey to brown dorsum speckled to varying degrees with creamy grey, tan, or black (brown with or without darker irregular blotches), and inhabits paramos on Andes of southern Colombia and northern Ecuador (Lynch 1972(Lynch , 1981.  Pristimantis loujosti and P. pycnodermis also stand out from other species of the genus by their stout body and thick glandular skin on dorsal surfaces of body and limbs, but they differ from P. andinogigas sp. nov. as follows (characters of P. andinogigas sp. Pristimantis pycnodermis (Lynch, 1979) differs by having low cranial crests (absent), snout subacuminate in dorsal view and truncate in lateral view (snout rounded in dorsal view; rounded to slightly protruding in lateral view), skin of flanks smooth (with large warts), fingers bear lateral fringes (absent), dark canthal and tympanic marks (head marks absent), large black spots on the flanks (brown with or without dark irregular blotches), 32.5-44.4 mm SVL in adult females (50.0-50.5 mm), and inhabits paramos on the Andes of central-southern Ecuador (Lynch 1979).
Description of holotype. Adult female (50.0 mm SVL, Fig. 2); head narrower than body, wider than long (head width 40% of SVL, head length 32% of SVL, head length 80% of head width); snout short (eye nostril 11% of SVL, eye nostril 87% of eye diameter), rounded in dorsal and lateral views; canthus rostralis rounded and weakly concave; loreal area concave; lips flared; eye large (eye diameter 1.14 times eyenostril distance, eye diameter 38% of head length); nostrils slightly protuberant laterally (Fig. 3). Cranial crest absent; upper eyelids without tubercles; tympanic membrane differentiated, tympanic annulus visible (tympanum diameter 35% of eye diameter), upper and posterior borders of tympanic annulus in contact with prominent, thick glandular patch that covers all dorsal fascia of m. depressor mandibulae; large, glandular postrictal tubercles. Choanas small and widely separated from each other, not concealed by palatal shelf of maxilla; dentigerous processes of vomer present, oblique, moderately separated, posteromedial to choanae, with four or five teeth; tongue longer than wide, posterior half not adherent to floor of mouth. Skin on dorsum thick and glandular, surface texture porous (Figs 1, 4), with large, flat, glandular warts on flanks; dorsolateral folds absent; thick glandular patch on dorsal surfaces of humeral, femoral, tibial and tarsal regions; glandular folds in wrists (Fig. 4); skin on venter areolate; discoidal fold weakly defined; skin on ventral surfaces of legs granular; cloaca not protuberant, cloacal region with large warts. Ulnar tubercle present but low; palmar tubercle flat and bifurcate; thenar tubercle elongate, about half the size of palmar tubercle; subarticular tubercles prominent, rounded in ventral and lateral views; supernumerary palmar tubercles rounded, smaller than subarticular tubercles; fingers without lateral fringes; Finger I shorter than Finger II; discs on fingers expanded and elliptical, most prominent on fingers II-IV, while disc on Finger I slightly expanded; all discs bearing ventral pads well defined by circumferential grooves (Fig. 3).
Hind limbs robust (tibia length 46% of SVL; foot length 49% of SVL); heel without tubercles; inner edge of tarsus with one wart low and poorly differentiated; inner metatarsal tubercle ovoid, about 5x round outer metatarsal tubercle; subarticular tubercles rounded; plantar supernumerary tubercles low and inconspicuous, smaller than subarticular tubercles; toes with narrow lateral fringes; basal toe webbing between toes II-V; discs of toes expanded, elliptical, slightly narrower than those on fingers, most prominent on fingers II-V, while disc on Finger I slightly expanded; toes with ventral pads well-defined by circumferential grooves; toe lengths, when adpressed, IV > V > III > II > I; Toe V longer than Toe III; disc of Toe III not reaching distal subarticular tubercle on Toe IV, disc on Toe V reaches middle of distal subarticular tubercle on Toe IV (Fig. 3).
Colouration of holotype in life. Dorsum dark brown; ventral surfaces dark brown with irregular light-yellow flecks and blotches on throat, hands, feet, armpits, and lower venter; iris golden-bronze with dense black reticulations (Fig. 5).
Colouration of holotype in preservative. Same pattern as in life, but brown surfaces turned dark grey (Fig. 2).
Variation. Males are smaller than females, measurements of the type series are provided in Table 1. Dorsal colouration of body and legs varies from dark brown, chocolate brown, or orange-brown (Fig 5.). Females are darker and have a homogeneous coloration pattern, while males are paler and usually with dark irregular blotches. Some individuals have pale pink flanks and dorsal surfaces of legs (Fig. 5D). Venter colouration varies from completely dark brown to dark brown with irregular lightyellow flecks and blotches. Background dorsal colouration of juveniles is paler, and dorsal dark blotches are darker.
Etymology. The specific epithet is coined from the New Latin adjective andinus (pertaining to the Andes) and the Latin noun gigas (giant). The name alludes to the large and stout body of this new species in comparison with other species of Pristimantis from the high Andes.
Distribution, natural history, conservation status, and extinction risk. Pristimantis andinogigas sp. nov. is only known from its type locality, the paramos of the Nudo de Cajanuma, at elevations between 3300 and 3400 m, on the Cordillera Oriental of the Andes of southern Ecuador (Fig. 7). Surveys in other localities of the Nudo de Cajanuma, and on the nearby Nudo de Sabanilla, have not recorded the species (Almendáriz andOrcés 2004, Ron et al. 2019). However, most surveys were conducted at lower elevations, and most paramos in the region lack amphibian inventories. It is possible that P. andinogigas inhabits a larger area at the Cajanuma-Sabanilla mountain ridges; but it is unlikely that it occurs farther north on the Cordillera Oriental (e.g., Nudo de Guagrahuma), because of separation by the valley of the River Zamora, reaching elevations as low as 2800 m that may limit species' dispersal. The ecosystem at the type locality is Paramo Bambusoid Meadow (MAE et al. 2013  . Pristimantis andinogigas was found active at night (19h00-22h00) at 6-10° C air temperature and 85-98% relative humidity. All males and some subadults and juveniles were observed active on bamboos (Neurolepis spp.); while both adult females were found active on the floor. During the day, individuals were found hidden inside rosettes (Senecio spp. and Puya spp.) or at the base of bamboos. Pristimantis andinogigas was the most abundant species during surveys at the type locality, representing 47 out of 108 anuran records. It was found in sympatry with Pristimantis percultus, Pristimantis sp. cf. colodactylus, Pristimantis sp. cf. orestes, and Lynchus sp.
The type locality of P. andinogigas is officially protected as part of the Podocarpus National Park, a national protected area created in 1982. The area has little anthropogenic impact, and in general, paramos of the Nudo de Cajanuma and the nearby Nudo de Sabanilla are reported to have a relatively good conservation status (Hofstede et al. 2002). Road infrastructure projects have been proposed in the past, but their development was cancelled (Cisneros et al. 2004, Bernardi de León 2009. However, three expeditions over the last five years have recorded very low numbers of P. andinogigas. Although more data are needed, it may be possible that the population of P. andinogigas has declined. In the absence of further information about the extinction risk on this newly discovered species, we suggest that P. andinogigas should be classified in the IUCN Red List category of Data Deficient (IUCN 2012).

Discussion
Pristimantis andinogigas sp. nov. is morphologically similar to several species formerly associated under the P. orcesi species-group (i.e., Pristimantis erythros, P. farisorum, P. obmutescens, P. orcesi, P. racemus, P. simoterus, P. simoteriscus, and P. thymelensis). However, we refrain from assigning it to any species-group in the absence of data to conduct an integrative phylogenetic analysis. Morphological characters in Pristimantis are by themselves unreliable to assess phylogenetic affinities, and most of the speciesgroups within Pristimantis that were solely defined on morphology have resulted nonmonophyletic (Pinto-Sánchez et al. 2012, Padial et al. 2014). The Pristimantis orcesi species-group proposed by Lynch (1981) was found to be non-monophyletic by Pinto-Sánchez et al. (2012) and Padial et al. (2014); although the relationships of most species remain unknown since both studies included only two species assigned to the P. orcesi species-group (P. orcesi and P. thymelensis).
Pristimantis andinogigas shows two notorious morphological characters that are not extended in the genus: glandular patches covering dorsal surfaces body and limbs, and porous dorsal skin texture. Similar glandular patches were first reported in P. pycnodermis by Lynch (1979), subsequently in P. loujosti by Yánez-Muñoz et al. (2010) and in P. erythros by Sánchez-Nivicela et al. (2018), and we have observed them in P. orcesi and an undescribed species of Pristimantis from the paramos of southern Ecuador. Porous skin texture has not been reported in any other species of Pristimantis, although it could have been confused with shagreen texture when not examined in detail or in preserved specimens. Further analyses are needed to understand the morphology of these characters and their phylogenetic significance.
Over the last decades, field studies in the Podocarpus National Park and nearby areas have revealed extraordinary flora and fauna diversity on the southernmost portion of the Cordillera Oriental of the Andes in Ecuador (Borchsenius 1997, Stattersfield et al. 1998, Brehm et al. 2005, Keating 2008, Rex et al. 2008, Richter et al. 2009). Although information on amphibians and reptiles has not been fully systematised and several areas remain unexplored, available data shows high levels of species richness and endemicity of amphibians and reptiles in the region (Lynch 1979, Cisneros-Heredia and McDiarmid 2006, Yánez-Muñoz et al. 2013, Torres-Carvajal et al. 2017. Further new species of amphibians and reptiles from the Podocarpus National Park, and the nearby Yacuri National Park, will be described in the near future, and discovery of additional new species from unexplored areas is expected.

Acknowledgments
This work is part of Programa de Investigación Red Terrarana del Ecuador of Instituto Nacional de Biodiversidad INABIO, developed with the support of Universidad Nacional de Loja, Laboratorio de Zoología Terrestre and Museo de Zoología of Universidad San Francisco de Quito USFQ, and Museo de Zoología QCAZ. We thank Karen Salinas who was part of the team that surveyed the herpetological diversity at Cajanuma, to José Villa Esparza and Enrique Armijos, park rangers of the Podocarpus National Park, for their field support, and to Rudolf von May and Alessandro Catenazzi for their comments as reviewers. Research was conducted under authorization by Ministerio del Ambiente del Ecuador. For access to collection specimens and working space, we thank Juan C Sánchez-Nivicela (Universidad del Azuay), Carolina Reyes-Puig (Museo de Zoología, Universidad San Francisco de Quito), Santiago R Ron (Museo de Zoología, Pontificia Universidad Católica del Ecuador PUCE), John D Lynch (Instituto de Ciencias Naturales, Universidad de Colombia), and Raúl Sedano (Colección Herpetológica, Universidad del Valle del Cauca). Revision of type specimens of Colombian Pristimantis was possible thanks to the support of Heinz Schneider of Basel Botanical Garden, Lou Jost, Javier Robayo and Juan P Reyes-Puig of Ecominga Foundation. Work by David Veintimilla-Yánez was supported by Universidad Nacional de Loja, Centro de Estudios y Desarrollo de la Amazonía CEDAMAZ, and Ministerio del Ambiente de Loja. Work by Diego F Cisneros-Heredia was supported by Universidad San Francisco de Quito USFQ (projects HUBI ID 48 "Taxonomía, Biogeografía y Conservación de Anfibios y Reptiles", ID 1057 "Impact of habitat changes on the biological diversity of the northern tropical Andes", ID 7703 "Estrés fisiológico y molecular en anfibios de los altos Andes tropicales", funded by a grant of the Colegio de Ciencias Biológicas y Ambientales COCIBA-USFQ, ID 12268 "Taxonomía y Conservación del género Pristimantis en los páramos, estribaciones y tierras bajas del Ecuador", ID 13524 "Desarrollo de una plataforma de bioinspiración médica a partir de la biodiversidad", funded by a grant of the Escuela de Medicina, Colegio de Ciencias de la Salud. COCSA-USFQ) and by Programa "Becas de Excelencia",