Bioacoustics of Adelophryne patamona

Adelophryne patamona can be distinguished from A. baturitensis by the presence of subdigital pads and absence of subarticular tubercles (tubercles present, pads absent in A. baturitensis ) and large size, up to 23 mm SVL (largest A. baturitensis 16.3 mm ). Adelophryne patamona can be distinguished from A. maranguapensis by its posterior cloacal opening, without a transverse flap (flap present, cloaca opening ventrally in A. maranguapensis ) and large size, up to 23 mm SVL (largest A. maranguapensis 17.4 mm ). Adelophryne patamona can be distinguished from A. gutturosa , with which it occurs sympatrically, by the following characters: second phalange of Finger IV relatively long, 2X its width (short, length equal to or slightly greater than width in A. gutturosa ); canthus rostralis concave (straight); vomerine teeth 15–16 (2–8); large size, up to 23 mm SVL (largest A. gutturosa 16 mm ) ( Fig. 1 ). In the field these species can be easily distinguished by their distinctly different advertisement calls (see below). Characters useful for distinguishing among species of Adelophryne are in Table 1 . Species Maximum SVL (mm) Finger Pha- langeal Formula Vo m e r i n e Teeth Finger Pads or Tubercles Dorsum Distribution adiastola 14 2-2-3-2 2–8 pads, 1-1-2-1 granular Amazonian Colum- bia and Perú baturiensis 16.3 2-2-3-3 3–8 tubercles, 1-1-2-2 smooth Ceará, Brazil gutturosa 16 2-2-3-3 2–8 pads, 1-1-2-1 smooth/ shagreened Guiana region maranguapensis 17.4 2-2-3-3 4–8 pads, 1-1-2-2 pustulous Ceará, Brazil pachydactyla 11.1 2-2-3-2 unknown pads, 2-3-4-2 smooth Bahia, Brazil patamona 23 2-2-3-3 15–16 pads, 1-1-2-1 smooth/ shagreened, tubercles Pakaraima Moun- tains, Guyana Description of the holotype . A male, 17 mm SVL, head slightly longer than wide, as wide as adjacent part of body, head depth 50% of width. Snout rounded in dorsal and lateral profile. Distance between snout tip and eye slightly less than eye diameter, eye-nostril distance slightly less than internarial distance, 2X distance from nostril to snout tip, 75% of distance from eye to snout tip. Canthus rostralis indistinct, rounded, concave; loreal region sloping steeply to upper lip. Nostrils not projecting, round, directed laterally. Interorbital distance 1.3X internasal distance, 2X upper eyelid width. Pupil horizontal. Temporal region vertical; tympanum small, distinct, round, 35% of eye diameter, surrounded by a distinct annulus, partially obscured by a supratympanic fold, separated from eye by a distance equal to tympanum diameter. Low glandular ridge from tympanum to arm insertion barely visible. Choanae small, laterally placed; vomerine processes transverse, posterior to choanae, each bearing 15 teeth. Tongue narrow, sides parallel, attached anteriorly. Vocal slits small, flanking tongue, vocal sac large, subgular. Skin of dorsum, venter, and limbs smooth with scattered small tubercles; flanks and rear of thighs areolate. Cloacal opening above midpoint of thigh, directed posteriorly, dorsal flap absent. Hand with large flat oval palmar and thenar tubercles. Underside of fingers with large flat subdigital pads (1–1–2–1); no pads under ultimate phalanges. Fingers flattened, unwebbed. Tips of fingers bluntly pointed, bearing discs not wider than the adjacent phalange, discs laterally grooved. Finger lengths I<IV<II<III; Finger IV relatively long, free part more than half that of Finger III. Phalangeal formula 2–2–3–3, second phalange of Finger IV twice as long as wide ( Fig. 1 ). Terminal phalanges of Fingers I, II and III T-shaped, that of Finger IV blunt. Distal portions of fingers surrounded by a transparent rim of skin ( Fig 2 ). Tarsus smooth, no ridge or tubercle. A large distinct oval flat inner and a smaller round conical outer metatarsal tubercle. Subdigital pads (1–1–2–3–2) large, flat, located just distally of digital articulations; no supernumerary pads. Toes flattened, unwebbed; toe V more slender than the others. Tips of toes dilated into small, narrow discs, those of Toes II, III, IV slightly wider than adjacent phalange, ending in asymmetrically pointed tips; those of Toes I and V equal to width of adjacent phalange, with rounded or bluntly pointed tips. Discs with lateral grooves. Toe lengths I<II<V<III<IV. Phalangeal formula 2–2–3–4–3; terminal phalanges Tshaped. Distal portions of toes surrounded by a transparent rim of skin, although this is much less prominent on the toes than it is on the fingers ( Fig 2 ). Heel of adpressed hindlimb reaches a point between eye and tip of snout. Heels overlap slightly when hindlimbs are flexed at right angles to sagittal plane of body. Shank length 57% of SVL. Colour of holotype in life. Ground colour of dorsum, flanks and dorsal surfaces of limbs medium brown. Central part of dorsum dark brown, bounded by a black middorsal “)(”-shaped mark and interorbital bar. Dorsum with a few other small, scattered black marks. Loreal and temporal regions dark brown. A black bar extending from tip of snout through eye to flank; another black bar in the inguinal region. Dorsal surfaces of limbs with black crossbands. Throat, chest and underside of arms dark grey with white or pale blue spots. Venter, underside of legs and rear of thighs reddish-brown with white or pale blue spots. A black anal spot. Palpebrum not reticulated, a black band along its upper rim. Iris copper with a red ring around pupil ( Fig 3 ). In preservative the venter becomes brownish-grey with white spots. Variation. The female paratype from Wokomung is the largest specimen collected, SVL 23 mm ( Fig 4 ). Paratypes from Maringma ( Figs. 5–7 ) are one male 18.4 mm SVL, five females 20.7–21.5 mm SVL, and two juveniles (11.8 and 11.9 mm SVL). Dorsal skin smooth to granular; ventral tubercles variable; vomerine processes each bearing 16–18 teeth in adults, 2–3 teeth in juveniles. Colouration is variable, not sexually dimorphic ( Figs. 4–7 ). Black dorsal markings are variable; some specimens are darker with more pale blue spots and more conspicuous tubercles on dorsum. In the specimens from Maringma the throat, chest and underside of arms are black with white or pale blue spots and a few reddish-brown dots; the venter, underside of legs and rear of thighs are reddish-brown, sometimes with very few white or pale blue spots ( Figs. 6–7 ). Juveniles resemble adults, but the upper arm is yellowish-orange and the dorsum has more pale blue spots; ventrally they are black with numerous pale blue spots ( Fig. 5 C). Vocalisation ( Fig. 8 ; Tables 2 , 4 ). The following description is based on a sample of six advertisement calls from a single male, IRSNB 1978, recorded on the southeast slope of Mount Maringma ( 05º 12' 16" N , 060º 34' 39" W , 1376 m ), on 24 November 2007 at 14h15, air temperature 19.8°C. Call parameter N Mean Range Call duration (s) 6 0.63 0.584–0.712 Inter-call interval (s) 5 3.85 3.365–4.255 Duration of first note (s) 6 0.038 0.035–0.042 Duration of second note (s) 6 0.056 0.055–0.057 Duration of third note (s) 6 0.429 0.400–0.497 Inter-note interval between the first and the second note (s) 6 0.075 0.072–0.081 Inter-note interval between the second and the third note (s) 6 0.052 0.047–0.059 Note repetition rate (notes/s) 12 9.07 8.66–9.26 Emphasized frequency (Hz) 18 3255 3251–3269 Temporal structure. The advertisement call of Adelophryne patamona consists of a group of three soft, unpulsed, whistle-like notes (two short, followed by one long) produced in rapid succession ( Fig. 8 ). Although a feeble isolated single whistle-like note was sometimes heard, we never observed the specimen emitting that note, and thus we cannot confidently attribute it to A. patamona . However it is possible that, like in A. gutturosa (see below), a shorter call is emitted when a female is very close to a male. Males typically call antiphonally and there was no overlapping of the calls. Call parameter N Mean Range Call duration (s) 27 1.27 0.058–2.392 Inter-call interval (s) 37 15.08 1.8–110.7 Number of notes 130 6.8 2–15 Note period (s) 235 0.143 0.043–0.219 Note repetition rate (notes/s) 29 8.58 6.06–22.22 Emphasized frequency (Hz) 227 4242 3896–4979 Spectral structure. Three harmonics are developed, with the fundamental frequency dominating (range: 3251–3269 Hz; mean: 3255 Hz). The distribution of sound energy decreases progressively through the higher harmonics. The frequency rises abruptly at the very beginning of the notes ( Fig. 8 ). The amplitude of the third note rises sharply to a peak at the beginning of the note then drops off rapidly, rising again, slowly, to a peak near the end of the note. A smaller peak in amplitude occurs at the end of the note ( Fig. 8 ). Vocalisation parameters of three Adelophryne species are compared in Table 4 . Call parameter A. adiastola A. gutturosa A. patamona sp. nov. Number of notes 1–10 2–15 3 Note repetition rate (note/s) 7 6.06–22.22 8.66–9.26 Pulses 2 4–5 high amplitude pulses followed by up 0 to 7 low amplitude pulses Emphasized harmonic Second First First Emphasized frequency (Hz) 3200–3700 3896–4979 3251–3269 Natural history . The specimens were collected at the end of the dry season, mostly at night, in leaf litter under medium-canopy forest ( Fig. 5 D). One female (IRSNB 1975) and the two juveniles (IRSNB 1976–7) were collected among rootlets at the base of a tree. One male, IRSNB 1978, was calling in the afternoon under leaves in a hole between roots. Many males were heard calling during afternoons and nights but were very difficult to find in their hidden calling sites. No enlarged ova were found in the females. The species was also heard on Maringma at 1414 m , and in high-canopy forest near the village of Wayalayeng ( 05º 14' 11" N , 060º 31' 04" W , 678 m ), but none were collected at these locations.