Adenomera aurantiaca, Carvalho & Moraes & Lima & Fouquet & Peloso & Pavan & Drummond & Rodrigues & Giaretta & Gordo & Neckel-Oliveira & Haddad, 2021

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 : 416-420

ADENOMERA AURANTIACA , SP. NOV.

ORANGE- LEGGEDTERRESTRIALNEST- BUILDINGFROG

( FIGS 2B, 3–4, 5G, 6G, 7G, 9E–F, 11E–F;

TABLES 1-3)

lsid urn:lsid:zoobank.org:act:EA632E5E-083B-4DAC-AA8A-67C513AFDD20

Holotype: INPA-H 40520 (field # DT 4327 ), adult male, BRAZIL, Pará , Trairão, 4.756617°S, 56.394333°W, 91 m, 30-x-2013, D. Pavan (Collector).

Paratypes: INPA-H 40518 (field # DT 3486 ), adult female , INPA-H 40519 (field # DT 4272 ), subadult, and INPA-H 40521 (field # DT 4117 ), juvenile, BRAZIL, Pará , Trairão, 4.883550 –5.073200 °S, 56.437950 – 56.440050 °W, 78–102 m, between 2012–2013, D. Pavan and L.J.C.L. Moraes (Collectors) .

Etymology: The epithet is derived from the Latin aurantiacus, the colour orange, referring to the brightly orange-coloured limbs of this species. Such a colour appears to be unique in the genus Adenomera .

Diagnosis: A. aurantiaca is characterized by the following combination of character states: (1) medium size (both adult specimens, one male and one female, with SVL = 20.9 mm); (2) robust body shape; (3) toe tips slightly to moderately expanded (character states B–C); (4) distal antebrachial tubercle on underside of forearm; (5) belly white and grey mottled, especially in life; (6) thigh surfaces brightly orange-coloured, especially in life; (7) multi-note advertisement call; (8) call notes formed by 5–7 complete pulses; (9) note duration varying from 112–137 ms; (10) note dominant frequency coinciding with the second harmonic (4102–4523 Hz); and (11) note fundamental frequency ranging from 2074–2246 Hz.

Comparisons with congeners: A. aurantiaca has adult specimens (SVL = 20.9 mm; Table 2) smaller than those of A. coca [23.6–25.6 mm ( Angulo & Reichle, 2008)], A. lutzi [25.7–33.5 mm ( Kok et al., 2007)] and A. simonstuarti [25.9–26.2 mm ( Angulo & Icochea, 2010)]. A. aurantiaca has a robust body shape ( Fig. 11E–F), whereas A. diptyx , A. martinezi and A. saci have a slender body. A. aurantiaca has slightly to moderately expanded toe tips (character states B–C), but not fully expanded into small discs (character state D) as in A. ajurauna , A. andreae , A. chicomendesi , A. heyeri , A. marmorata , A. lutzi , A. nana and A. simonstuarti . A. aurantiaca is distinguished from congeners (except A. amicorum , A. cotuba , A. kayapo , A. lutzi and A. phonotriccus ) by having an antebrachial tubercle on underside of forearm. A. aurantiaca differs from A. araucaria , A. bokermanni , A. heyeri , A. kweti , A. lutzi and A. nana by having ventral surfaces mottled white and grey ( Fig. 9F)—these are yellow or sometimes with yellowish tints in the other species. A. aurantiaca is further distinguished from congeners by having orange-coloured limbs, particularly bright orange on the thigh and groin in life ( Figs 9E–F). Other Adenomera species might have tints of orange and yellow on groin and hindlimbs; however, A. aurantiaca is the only species in the genus exhibiting a bright orange colouration, extending also over the shank and tarsus. The advertisement call of A. aurantiaca ( Figs 5G, 6G, 7G; Table 3) is given as multi-note calls. Such a call pattern distinguishes the new species from congeners having single-note calls, either pulsed or non-pulsed ( Table 3). The only three species of Adenomera with multi-note calls are A. amicorum ( Fig. 5E), A. cotuba ( Fig. 5B) and A. simonstuarti (T.R. de Carvalho, pers. obs.), from which the new species is distinguished by having notes with complete pulses (call notes with partly fused pulses in the other three species).

Description of holotype ( Fig. 11E–F): Body robust. Snout 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 rounded; 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 third. Relative finger lengths IV <I ≃ II <III; fingers without ridges or fringes; finger tips rounded, slightly expanded in fingers I and IV; inner metacarpal tubercle ovoid; outer metacarpal tubercle nearly rounded. Subarticular tubercles nearly rounded; supernumerary tubercles rounded. Antebrachial tubercle on underside of forearm, single, nearly rounded. Dorsum mostly smooth, flank warty. Tubercles on posterior surface of tarsus. Ventral surface of body smooth; underside of thigh granular. Paracloacal gland nearly rounded. 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, tip of toe V slightly expanded. Inner metatarsal tubercle ovoid, outer metatarsal tubercle nearly rounded, inner tubercle twice the maximum diameter of the outer tubercle. Tarsal fold extending 1/2 of tarsus length, from the inner metatarsal tubercle ending in a tubercle separated from the fold by a short gap. Subarticular tubercles nearly rounded or subconical; supernumerary tubercles rounded. Measurements are given in Table 2.

Snout tip with a faded white coloration (coincident with the fleshy ridge). Blotches on the upper lip white. Postcommissural gland mostly covered with melanophores light grey and dark brown. Tympanum light brown. Dorsal surface of body and limbs varying from light to dark brown; forelimbs brown and creamcoloured. Body with darker, large blotches and offwhite smaller blotches in the last third of body length; limbs with dark brown transverse bars. Posterior surface of thigh pale yellow with scattered brown stains; paracloacal gland off-white. Dorsolateral stripe absent; an indication of a mid-dorsal longitudinal line, fragmented and mostly indistinct, light brown. Throat, chest, belly and underside of limbs partly translucent, cream-coloured. Spots on throat and chest white on a fine brown mottling; belly brown-mottled. Underside of forearm (outer margin), palm of hand, sole of foot, digits and subarticular tubercles mostly brown and light grey; tips of fingers and toes non-pigmented.

Colour of holotype in life ( Fig. 9E–F): Dorsum covered with black speckles and spots irregularly distributed on a grey and brown background. Iris copper. Tympanum dark brown. Dorsal surface of arms, legs and groin bright orange and brown. Mid-dorsal longitudinal stripe light grey, postcommissural gland yellow, white and dark grey. Flank white and dark grey mottled. Throat and chest with white speckles on a dark brown background, belly white and grey, intensely mottled laterally. Ventral surface of legs bright orange, violet and light grey.

Variation in type specimens: Variation is restricted to colour patterns, which are related to mottling on belly (extensive or sparse) and throat (colour intensity, spotted/mottled). The female INPA-H 40518 has the snout shape nearly rounded from above and rounded in profile, fleshy ridge and paracloacal gland absent.

Advertisement call: Description based on calls of two males (N = 23 notes and 135 pulses quantified; Table 3). The call ( Figs 5G, 6G, 7G) consists of a multi-note signal given once or twice per minute. Calls are composed of 8–12 (9 ± 2; N = 2) notes given at a rate of 2–3 (2 ± 1; N = 2) per second. Notes are formed by 5–7 (6 ± 1) complete pulses given at a rate of 40–69 (51 ± 3) per second and varying in duration from 5–36 (13 ± 1) ms. Note duration varies from 112–137 (122 ± 4) ms and note rise time from 38–78 (50 ± 8)% of note duration. The note frequencies are harmonically structured and the dominant frequency coincides with the second harmonic (4102–4523, 4337 ± 86 Hz). The note fundamental frequency ranges from 2074–2246 (2120 ± 42) Hz. Frequency modulation is upward in most cases, with a single call modulating slightly downward, varying from –47 to 609 (408 ± 96) Hz.

Habitat and natural history: A. aurantiaca inhabits non-flooded primary forests, even though the species appears to occupy clearing sites with some sunlight as a preferred calling habitat. The breeding season is concentrated at the onset of the rainy season (October–November), when several males can be heard during the daytime, calling hidden amidst clumps of fallen branches on the forest floor or next to the base of terrestrial palm trees. A. andreae is the only congener found syntopically with the new species.

Distribution: A. aurantiaca is associated with lowland forests on the east bank of the middle Tapajós River in eastern Brazilian Amazonia. The distribution range appears to be limited to the east bank of the Jamanxim River ( Fig. 2B).