Tapajos

Carvalho, Thiago R. D., Moraes, Leandro J. C. L., Lima, Albertina P., Fouquet, Antoine, Peloso, Pedro L. V., Pavan, Dante, Drummond, Leandro O., Rodrigues, Miguel T., Giaretta, Ariovaldo A., Gordo, Marcelo, Neckel-Oliveira, Selvino & Haddad, Célio F. B., 2021, Systematics and historical biogeography of Neotropical foam-nesting frogs of the Adenomera heyeri clade (Leptodactylidae), with the description of six new Amazonian species, Zoological Journal of the Linnean Society 191, pp. 395-433 : 422-424

TAPAJÓS TERRESTRIAL NEST- BUILDING FROG

( FIGS 2A, 3–4, 5I, 6I, 7I, 10C–D, 12C–D;

TABLES 1-3)

lsid urn:lsid:zoobank.org:act:366E654C-AC84-42B8-9303-DC28675C9E5F

Holotype: INPA-H 40516 (field # DT 3886 ), adult male, BRAZIL, Pará , Itaituba, 5.052133°S, 56.876833°W, 78 m, 8-xii-2012, D. Pavan (Collector).

Paratypes: INPA-H 40515 (field # DT 3180 ), adult female, BRAZIL, Pará , Itaituba, 4.673833°S, 56.446717°W, 87 m, 4-vii-2012, D. Pavan (Collector) . CZPB-AA 2118 (field #J153), adult male, BRAZIL, Pará , Juruti, Igarapé do Mutum, 2.611931°S, 56.185492°W, 118 m, 24-iii-2011, M. Gordo (Collector) .

Etymology: The epithet is derived from the Tapajós River. The distribution range of A. tapajonica comprises a swathe of land entailing the west bank of the middle-lower Tapajós River , limited to the south of the Amazon River ( Fig. 2A).

Diagnosis: A. tapajonica is characterized by the following combination of character states: (1) relatively large size (adult male SVL = 23.6–25.6 mm); (2) robust body shape; (3) toe tips moderately to fully expanded into small discs (character states C–D); (4) distal antebrachial tubercle on underside of forearm; (5) belly immaculate, cream-coloured; (6) thigh surfaces brightly orange-coloured, especially in life; (7) singlenote advertisement call; (8) call note formed by 3–5 partly fused pulses; (9) note duration varying from 66–89 ms; and (10) note dominant frequency coinciding with the fundamental harmonic (1873– 2003 Hz; N = 1 male) and second harmonic (4055–4430 Hz; N = 1 male).

Comparisons with congeners: A. tapajonica has adult males (SVL = 23.6–25.6 mm; Table 2) smaller than those of A. lutzi [25.7–33.5 mm ( Kok et al., 2007)] and A. simonstuarti [25.9–26.2 mm ( Angulo & Icochea, 2010)] and larger than A. ajurauna [17.2–20.0 mm ( Berneck et al., 2008)], A. araucaria [17.4–19.3 mm ( Carvalho et al., 2019b)], A. aurantiaca (20.9 mm), A. kweti [15.4–19.3 mm ( Carvalho et al., 2019b)], A. kayapo (17.5–21.0 mm), A. nana [16.3–19.4 mm ( Kwet, 2007)] and A. phonotriccus [19.8–21.6 mm ( Carvalho et al., 2019c)]. A.tapajonica has a robust body shape ( Fig. 12C–D), whereas A. diptyx , A. martinezi and A. saci have a slender body. A. tapajonica has toe tips that are moderately to fully expanded into small discs (character states C–D), differing from species having unexpanded or slightly expanded toe tips (character states A–B) as in A. bokermanni , A. coca , A. cotuba , A. diptyx , A. hylaedactyla , A. juikitam , A. martinezi , A. saci and A. thomei . A. tapajonica is distinguished from congeners (except A. amicorum , A. aurantiaca , A. cotuba , A. inopinata , A. kayapo , A. lutzi and A. phonotriccus ) by having an antebrachial tubercle on underside of forearm. A. tapajonica differs from A. araucaria , A. bokermanni , A. heyeri , A. kweti , A. lutzi and A. nana by having belly cream-coloured ( Fig. 10D), this is yellow or sometimes has yellowish tints in the other species. A. tapajonica can be further distinguished from some members of the A. heyeri clade ( A. amicorum A. kayapo and A. phonotriccus ) by lacking a dorsolateral stripe; such a colour feature is present in some specimens of the other three species. A. tapajonica is also distinguished from congeners (except A. aurantiaca and A. inopinata ; Figs 9E–F, 10B) by having thighs and groin orange-coloured ( Fig. 10D). From A. aurantiaca , A. tapajonica differs in thigh colour patterns in life: both species share the orange coloration; however, the major pattern in A. aurantiaca is brighter and more extensively distributed over the groin, hindlimbs and forelimbs ( Fig. 9E–F), whereas the pattern in A. tapajonica is relatively duller, orange-brown, and does not extend over the dorsal surface of hindlimbs and forelimbs ( Fig. 10C–D). The three new Adenomera species with distinctively orange-coloured thighs ( A. aurantiaca , A. inopinata and A. tapajonica ) can be distinguished from each other by their distinct calls.

The advertisement call of A. tapajonica ( Figs 5I, 6I, 7I; Table 3) is given as single notes. Such a call pattern distinguishes the new species from congeners having multi-note calls ( A. amicorum , A. aurantiaca , A. cotuba , A. inopinata and A. simonstuarti ; Fig. 5; Table 3). A. tapajonica is distinguished from eight congeners with non-pulsed calls by having a pulsed call (see Table 3). From the ten congeners also having single-note, pulsed calls, A. tapajonica is distinguished from A. andreae by having a call note with a lower fundamental frequency ( Table 3), from A. coca , A. juikitam , A. martinezi and A. thomei by having fewer pulses per note ( Table 3), from A. araucaria and A. heyeri by a shorter note duration ( Table 3), and from A. diptyx and A. hylaedactyla [combined repetition rate of 107–242 notes/min ( Márquez et al., 1995; Carvalho et al., 2019d)] by a lower note repetition rate (87–98 ms). The call of A. tapajonica is formed by partly fused pulses ( Figs 6I, 7I), whereas that of A. phonotriccus is formed by complete pulses ( Figs 6F, 7F).

Description of holotype ( Fig. 12C–D): Body robust. Snout subovoid to rounded in dorsal view, acuminate in lateral view. Nostril closer to the snout tip than to the eye, fleshy ridge on snout tip, canthus rostralis not marked, loreal region slightly concave, supratympanic fold from the posterior corner of the eye to the base of the arm, postcommissural gland ovoid, vocal sac subgular with a fold from jaw extending to forearm, vocal slit present, vomerine teeth in two straight rows medial and posterior to choanae and oblique to sagittal plane. Tongue elongated, free from the posterior half. Relative finger lengths IV <I ≃ II <III, fingers without ridges or fringes, finger tips rounded, unexpanded, inner metacarpal tubercle ovoid, outer metacarpal tubercle nearly rounded. Subarticular tubercles nearly rounded, supernumerary tubercles rounded. Antebrachial tubercle single, rounded. Anterior dorsum smooth, posterior dorsum glandular, flank warty. Dorsolateral fold extending posteriorly from scapular region to the groin, dorsal fold lies behind the upper eyelid and extends posteriorly until 2/3 body length. Dorsal surface of shank and posterior surface of tarsus covered with white-tipped tubercles. Paracloacal gland indistinct. Ventral surface of body and limb mostly smooth, underside of thigh areolate/ granular in contact with ventral surface. Relative toe lengths I <II <V <III <IV, lateral fringing and webbing absent, tips of toes II–IV moderately expanded (character state C), tip of toe I unexpanded, toe V desiccated. Inner metatarsal tubercle elongated, outer metatarsal tubercle ovoid. Tarsal fold extending 1/3 of tarsus length, from the inner metatarsal tubercle towards the heel. Subarticular tubercles nearly rounded or subconical, supernumerary tubercles nearly rounded. Measurements (in mm): SVL 23.6, HL 7.9, HW 8.4, ED 2.1, TD 1.5, EN 1.8, IND 2.1, HAL 4.8, TL 9.8, THL 10.0, FL 10.8.

Snout tip with a faded white coloration (coincident with the fleshy ridge). Blotches on the upper lip offwhite. Postcommissural gland pale yellow. Tympanum light brown. Dorsal surfaces of body and limbs brown, lighter on forelimbs and heel region, digits of hand off-white. Anastomotic blotches on dorsum blackish brown; transverse bars and blotches on limbs blackish brown. Posterior surface of thigh finely mottled in shades of brown and yellow, paracloacal gland pale yellow. Dorsolateral stripe absent, an indication of mid-dorsal, longitudinal line light grey, fragmented and restricted to the pelvic region. Ventral surface of belly and thigh partially translucent, yellowish cream. Off-white blotches on lower jaw and chest. Throat finely mottled, belly immaculate. Underside of forearm dark brown. Tubercles partly pigmented, grey, tips of fingers and toes non-pigmented.

Colour of holotype in life ( Fig. 10C–D): Dorsum covered with anastomotic blotches blackish brown on a brown background. Iris golden. Tympanum brown, an orange coloration partly surrounding the tympanic annulus. Arms and legs with transverse stripes and blotches dark brown. Mid-dorsal longitudinal stripe and postcommissural gland pale yellow and dark brown. Flank finely mottled, greyish brown; glands yellow. Throat and chest brown-spotted on a partly translucent violet background, lower jaw covered with white spots, belly cream-coloured, immaculate. Underside of limbs partly translucent; outer surface of forearm dark brown with a medial, poorly delimited stripe, off-white, hindlimbs translucent, bright orange on anterior and posterior surfaces, and groin, underside of thigh granular, pale yellow.

Variation in type specimens: The female INPA-H 40515 has snout shape rounded in dorsal and lateral views and paracloacal gland absent. The male CZPB-AA 2118 has tip of toe IV fully expanded (character state D). Dorsal surfaces of body and limbs lighter brown in both paratypes.

Advertisement call: Description based on calls of two males (N = 18 notes and 70 pulses quantified; Table 3). The call ( Figs 5I, 6I, 7I) consists of a single-note signal given at a rate of 52–59 (55 ± 5; N = 2) per minute. Notes are formed by 3–5 (4 ± 1) partly fused pulses given at a rate of 39–89 (68 ± 16) per second and varying in duration from 7–51 (21 ± 2) ms. Note duration varies from 66–89 (82 ± 7) ms and note rise time from 5–63 (35 ± 29)% of note duration. The note frequencies are harmonically structured and the dominant frequency may coincide either with the fundamental harmonic (1873–2003, 1926 ± 61 Hz, N = 1 male) or with the second harmonic (4055–4430, 4223 ± 171 Hz, N = 1 male). Frequency modulation is upward, rising to 43–375 (206 ± 67) Hz.

Habitat and natural history: A. tapajonica is rarely recorded in the field. The species inhabits non-flooded primary forests on the west bank of the middle-lower Tapajós River. At the type locality, a single male (holotype) was collected during the rainy season (December), while calling on the leaf litter next to the base of a terrestrial palm tree. The female was collected from a pitfall trap. At Juruti, a few males of A. tapajonica were observed calling sparsely on the leaf litter in plateau areas of an old-growth nonflooded forest around sunset time. A. tapajonica was found sympatrically with two other Adenomera species ( A. andreae and A. hylaedactyla ) at the Juruti site.

Distribution: A. tapajonica is known from the type locality and a second nearby locality on the west bank of the middle Tapajós River , and from the Juruti site (near Igarapé Mutum) located in the intervening swathe of land between the Amazon River and the lower Tapajós River ( Fig. 2A).