Noblella personina Harvey, Almendáriz, Brito & Batallas, 2013

Harvey, Michael B., Almendáriz, Ana, Brito, Jorge & Batallas, Diego, 2013, A new species of Noblella (Anura: Craugastoridae) from the Amazonian Slopes of the Ecuadorian Andes with Comments on Noblella lochites (Lynch), Zootaxa 3635 (1), pp. 1-14 : 3-10

Noblella personina Harvey, Almendáriz, Brito & Batallas new species

( Fig. 1 )

Holotype. An adult male (EPN 14324, bearing field tag DBR 177) collected by Jorge Brito from forest at the Sardinayacu Lake Complex (Cantón Morona, Parroquia Sinaí), Morona Santiago, Ecuador, 2° 03’ 48.4” S, 78° 14’ 11.3” W, 1916 m, 27 December 2010.

Paratypes (6). Two adult males (EPN 14326 and 14327) collected by Diego Batallas on 23 December 2010 at 2° 04’ 47.8” S, 78° 11’ 51” W, 1647 m, two adult females (EPN 14325 and 14328) collected by Jorge Brito at 2° 03’ 48.4” S, 78° 14’ 11.3” W, 1916 m, 25 February 2011, and an adult male (EPN 14330) and adult female (EPN 14329) collected by J. Brito on 28 October 2011 at 2° 04’ 27.4” S, 78° 12’ 46.1” W, 1776 m in the Sardinayacu Lake Complex.

Diagnosis. A species of Noblella as defined by Hedges et al. (2008) reaching 17.9 mm SVL in females and 16.3 mm in males and distinguished from all congeners by (1) skin on dorsal body mostly smooth with few low pustules most dense on posterior half of body; dorsal head, dorsal limbs, and flanks smooth; (2) tympanic annulus and membrane clearly visible, its dorso-posterior edge covered by indistinct supratympanic fold; (3) snout rounded in dorsal view, subtruncate in profile (eye-nostril distance 28–36% of head length); (4) dentigerous process of vomer and teeth absent; (5) fingers not expanded distally; finger tips acuminate; Finger I shorter than Finger II; nuptial pad not visible; fingers with indistinct marginal grooves, at least on Fingers III and IV; (6) distal phalanges T-shaped; phalangeal formula of hands 2, 2, 3, 3; (7) supernumerary palmar tubercles present at base of Fingers II—IV; subarticular tubercles rounded; antebrachial ornamentation absent; (8) one elongate tarsal tubercle; two prominent metatarsal tubercles; supernumerary plantar tubercles absent; toes slightly expanded and acuminate distally; (9) Toe V shorter than Toe III; (10) palmar and pedal digital pads and ungual folds pointed (i.e., papilla of digital pad not projecting distally beyond ungual fold), separated by marginal grooves; (11) in preservative, adults with distinctive charcoal chin contrasting with mostly immaculate white ventral body; charcoal band on side of body not extending onto flanks; dorsum with two poorly defined, smudge-like chevrons; short charcoal stripe above inguinal region parasagittal, one on each side.

Comparisons. The new species superficially resembles frogs in Adelophryne and Phyzelaphryne . Although not yet reported from the Andes (Fouquet et al. 2012), these two genera are widely distributed in Amazonia and the Atlantic Forest Biome. We assign the new species to Noblella as defined by Duellman (1991), De la Riva et al. (2008), Hedges et al. (2008), and Heyer (1977) rather than one of these genera, because it has a tarsal tubercle and marginal grooves completely encircling the digital pads, whereas both Adelophryne and Phyzelaphryne have tarsal folds, and grooves are present only on the sides of the digital pads of Adelophryne . Frogs of the genus Noblella are morphologically similar and closely related to Barycholos (Heinicke et al. 2007; Hedges et al. 2008). We assign the new species to Noblella rather than Barycholos (characters in parentheses), because it lacks dentigerous processes of the vomers (present), has a short first finger (Finger I longer than Finger II), and has low, rounded subarticular tubercles (subarticular tubercles projecting).

The new species is noticeably more gracile than Ecuadorian congeners ( Fig. 1 ). Unlike Noblella carrascoicola , N. lochites , N. myrmecoides , and N. ritarasquinae , the new species has three phalanges in Finger IV. In Noblella personina , the charcoal mask fades abruptly at the level of the scapula, leaving the flanks lightly pigmented. Circular suprainguinal spots are absent, although a charcoal stripe running parasagittally is poorly defined. Except in rare patternless specimens, the mask extends to the inguinal region and suprainguianal spots are present in all other congeners except N. duellmani and N. pygmaea . However, N. pygmaea has tubercular skin and occurs above 3000 m in Cusco, Peru, and N. duellmani lacks a tympanum and marginal grooves on the toes (Lehr & Catenazzi, 2009; Lehr et al., 2004).

Noblella coloma and N. heyeri are the only other species of Noblella in Ecuador with three phalanges in the fourth finger. Unlike the new species, both N. coloma and N. heyeri have suprainguinal spots and an extensive facial mask extending to the inguinal region. Unlike the new species (characters in parentheses), N. coloma also has a finely shagreened dorsum (dorsum with few low tubercles, most dense posteriorly), smooth finger tips lacking marginal grooves (grooves present on Fingers III and IV), and an orange venter (pale yellow or yellow). Noblella heyeri is a smaller species with males reaching 12.9–14.1 mm SVL (n = 5) and females 13.1–15.9 mm SVL (n = 4; Lynch 1986; vs. males 14.7–16.3 mm and females 15.6–17.9 mm; Table 1 ). The fingers of N. heyeri lacks marginal grooves (present on Fingers III and IV) and have rounded digital tips (pointed).

Noblella myrmecoides occurs on the eastern slopes of the Andes in Ecuador and might be confused with N. personina . Unlike the new species (characters of N. personina in parentheses), N. myrmecoides has two phalanges in Finger IV (three), papillae extending distally from its digital pads (papillae absent), and usually suprainguinal spots and an extensive facial mask extending to the inguinal region (spots absent, facial mask fading at arm).

Most morphometric ratios broadly overlap among Noblella lochites , N. myrmecoides , and N. personina ( Table 1 ). Noblella myrmecoides appears to have a shorter shank than N. personina , however we could not show this statistically (F 11,7 = 3.283, P = 0.09), perhaps because of small sample sizes.

Character N. personina N. lochites N. myrmecoides

Males Females Males Females Males Females (n = 4) (n = 3) (n = 6) (n = 13) (n = 7) (n = 4) Eye-Nostril Length/Head Length 28–31% 28–36% 23–31% 24–45% 25–34% 24–43% (29 ± 2) (32 ± 4) (27 ± 3) (32 ± 8) (30 ± 3) (33 ± 8) Description of holotype. Adult male (16.3 mm SVL); head not distinct from body, its length 26% of SVL; head wider than long (head width 124% of head length, Fig. 2 ); dorsal surface of head (including eyelids) smooth; eye-lid width 57% of interorbital distance; region between nostrils not depressed; snout rounded in dorsal view, subtruncate in profile; nostril oval with short groove in antero-dorsal corner, directed laterally, slightly protuberant; canthus rostralis rounded; lores flat; eye large, 43% of head length, its diameter 1.36 times as large as its distance from the nostril; lips slightly flared between ventral margin of eye and antero-ventral margin of tympanum; tympanum distinct, slightly oval with its largest diameter vertical; length of tympanum 46% of eye diameter; tympanic annulus distinct; low, indistinct supratympanic fold overlapping dorso-posterior edge of tympanic annulus and extending obliquely to scapular region; elongate, tubercular ridge extending from rictus to insertion of arm, oriented obliquely at about 30° to horizontal.

Doral body mostly smooth with few low pustules denser posteriorly; skin on flanks and limbs smooth; no trace of glands in inguinal region; skin of ventral body and gular region smooth to very finely areolate.

When adpressed, Finger 3> 4> 2> 1 ( Fig. 2 ); digital tips of fingers sharply pointed; marginal grooves present on Fingers III and IV; digital formula of fingers 2, 2, 3, 3; manual subarticular tubercles rounded; distal subarticular tubercle of Finger IV absent (large, flat, oval supernumerary tubercle under penultimate phalanx of Finger IV); palm fleshy and swollen; three flat, round supernumerary tubercles, each positioned proximal to subarticular tubercle of Fingers II—IV; thenar tubercle flat and oval about half as large as round palmar tubercle; antebrachium unornamented.

When adpressed, Toe 4> 3> 5> 2> 1; ungual fold and digital pads of toes sharply pointed, separated by marginal grooves (i.e., papilla of pad not projecting beyond distal margin of each toe); digital tip of Toe V noticeably reduced relative to Toes III—IV; pedal subarticular tubercles oval, low and rounded in profile; pedal supernumerary tubercles absent; inner metatarsal tubercle oval, rounded and low in profile; outer metatarsal tubercle round, rounded in profile but of noticeably higher relief than inner tubercle; tarsal tubercle oval, rounded in profile, positioned near preaxial edge on ventral surface of tarsus.

Choanae small and circular, positioned far anterior and laterally, widely separated from one another and almost vertical in roof of mouth; dentigerous processes of vomer and vomerine teeth absent; tongue relatively small, subcircular, lacking posterior notch and medial process, free for one-fourth its length; vocal slits paired, elongate (each about half as long as tongue), positioned laterally in floor of mouth; extending from level of middle of eye to level of posterior edge of tympanum; vocal sac distended, single.

Coloration in preservative: Dorsum gray with diffuse charcoal mottling; charcoal interorbital bar slightly arched medially; dorsum with two poorly defined markings, large irregular blotch immediately behind interorbital bar, another large blotch overlapping anterior end of sacrum; parasagittal charcoal band just above flanks from leg to about level of anterior end of sacrum; charcoal pigmentation on limbs in poorly defined bands; wide dark charcoal mask from tip of snout rapidly fading on flank behind arm, covering entire side of head; tympanic membrane brown, distinctly contrasting with charcoal skin surrounding it; flanks and sides of limbs like dorsum but lighter (no charcoal band on flanks); large triangular cloacal blotch darkest along its lateral and dorsal margins; except for cloacal blotch, postaxial skin of thighs brown, densely and uniformly speckled with cream; venter white, diffusely flecked with melanophores; gular region mottled, darkest under mandible and in mental region; palms and soles charcoal, completely lacking cream spots; dorsal pigmentation extending to ventral surfaces of arms although leaving midventral white patches; melanophores forming diffuse reticulum on ventral surfaces of legs; free edge of palpebrum distinctly charcoal; rest of palpebrum uniformly and only slightly opaque (likely transparent in life).

Measurements (mm) of holotype: snout-vent length 16.3; head length 4.2; head width 5.2; eye diameter 1.8; eye-nostril distance 1.3; diameter of tympanum 0.8; eyelid width 1.2; interorbital distance 2.1; hand length 3.1; length of foot 7.8; length of shank 8.2.

Variation. In preservative, coloration of the paratypes resemble that of the holotype. All lack a charcoal band on the flanks. They all have white bellies and dark gular areas (even the females) with noticeably darker pigment below the mandible. In each, there is at least a trace of a charcoal band above the inguinal region and a triangular cloacal blotch. EPN 14325 has bolder markings overall. In this specimen and EPN 14326 3/3 transverse bands can be counted on each tibia and, as in most frogs, the bands extend across the shank and foot when the legs are folded into a sitting position. No sexual dichromatism is evident in this species.

In life, Noblella personina ranges from charcoal to brown with scattered darker marking and tiny cream spots ( Fig. 3 ). In some species, light tan areas edge dark charcoal to black markings on the dorsal body and head. The rictal gland is white contrasting with the charcoal supratympanic fold. The skin covering the tympanum is fleshcolored. When present, light markings on the limbs are tan to yellow. The venter is pale to bright yellow with brown reticulation. The iris is dark brown with red marbling noticeably denser above the pupil. The ciliary ring is mostly black ventral to the pupil and red dorsal to the pupil.

Adult females lack vocal slits.

Etymology. The specific name personina is an adjective derived from the Latin word persona, meaning mask, especially as worn by an actor. A diminutive suffix calls attention to the greatly reduced mask that readily differentiates Noblella personina from Ecuadorian congeners.

Vocalizations. Noblella personina emits at least two different kinds of advertisement calls of modulated frequency: a simple call emitted in isolation and a more complex call emitted when conspecifics are calling nearby.

We recorded vocalizations from the holotype (EPN 14324) on 27 December 2010 at 19°C. The advertisement calls of this individual lasted 570–1524 milliseconds (ms) (1052 ± 307, n = 20 calls) and consisted of 5–11 short notes lasting 13–20 ms (16 ± 2) each. Intervals of 103–166 ms (128 ± 14) separated the notes. This specimen’s advertisement calls included notes of relatively uniform frequency and amplitude ( Table 2 ; Fig. 4 ). Such calls are typical of individual males calling in isolation.

More complex calls recorded from two other specimens were likely emitted in response to conspecifics nearby. The advertisement calls of EPN 14326 (recorded 28 December 2010 at 19° C) lasted 549–4335 ms (1063 ± 660, n = 54 calls) and consisted of 4–23 notes lasting 7–20 ms (15 ± 2) each. Intervals of 119–230 ms (163 ± 19) separated the notes. A conspecific calling nearby answered each note, suggesting that this call is an aggressive call.

Finally, calls of a third specimen (EPN 14327, recorded 24 February 2011, 19.3° C) lasted 481–4926 ms (1464 ± 1055, n = 18) and consisted of 4–31 notes lasting 10–22 ms (17 ± 2) each. Intervals of 95–245 ms (150 ± 22) separated the notes. Unlike the holotype, calls of this individual included short and long notes with considerably more structural variation.

Distribution and Natural History. Noblella personina occurs in primary forest and in vegetation along the edge of lakes at the type locality ( Fig. 5 ). The area of the type locality is part of the “Herbazal Lacustre Montano Bajo” formation (Cerón, 2001). We found individuals of the type series in leaf litter of swampy, densely vegetated areas adjacent to the lakes during the day. This species takes refuge under exposed tree roots and decomposing logs.

During our surveys, male Noblella personina called throughout the day from at least 5:15–20:10 hrs. Calling was most intense after rains.

Other terraranan frogs occurring in sympatry with Noblella personina include Pristimantis bicantus , P. diadematus , P. eriphus , P. nigrogriseus , P. galdi , P. prolatus , P. quaquaversus and P. i n c o m p t u s.

Figures

FIGURE 1. Paratypes of Noblella personina (A – B, adult male, EPN 14330, SVL 15.2 mm; C, adult female, EPN 14329, SVL 17.4 mm; and D, adult male, EPN 14326, SVL 15.7 mm) from Sardinayacu Lake Complex, Morona Santiago, Ecuador.

FIGURE 2. Cephalic, palmar, and plantar morphology of Noblella personina (holotype, EPN 14324).

FIGURE 3. Dorsal and ventral morphology of Noblella personina (from left to right: EPN 14325 [female, SVL 15.6 mm], 14328 [female], and 14324 [male holotype]).

FIGURE 4. Oscilograms and sonograms of advertisement calls from three individuals of Noblella personina (A: holotype EPN 14324; B: EPN 14327; C: EPN 14326).

FIGURE 5. Collection localities of specimens of Noblella examined in this study (areas above 500 and 1000 m shaded gray).

Tables

TABLE 1. Mensural characters of three species of Noblella from the Amazonian slopes of the Ecuadorian Andes. In parentheses, mean ± standard deviation follows each range.

Snout-vent Length (mm, SVL)	14.7–16.3 15.6–17.9 (15.5 ± 0.7) (17.0 ± 1.2)	13.4–15.3 (14.2 ± 0.7)	12.9–19.4 (17.2 ± 1.8)	10.1–11.9 (11.1 ± 0.7)	13.0–14.7 (13.6 ± 0.8)
Head Length/SVL	26–32% 28–30% (30 ± 3) (29 ± 1)	28–35% (31 ± 2)	26–32% (29 ± 2)	26–34% (30 ± 2)	22–32% (29 ± 4)
Head Width/Head Length	98–124% 101–117% (108 ± 12) (107 ± 9)	104–123% (112 ± 7)	99–133% (115 ± 10)	104–127% (117 ± 9)	110–149% (123 ± 18)
Eye Diameter/Head Length	31–43% 38–41% (35 ± 5) (39 ± 1)	34–40% (36 ± 2)	24–41% (33 ± 5)	32–39% (35 ± 3)	34–42% (37 ± 4)

TABLE 2. Vocalization parameters of Noblella personina. In parentheses, mean ± standard deviation follows each range. All measurements of time are in milliseconds.

Parameter	EPN 14324	EPN 14326	EPN 14327
Number of Vocalizations Analyzed	20	54	18
Temperature (°C)	19.0	19.0	19.3
Dominant Frequency (Kilohertzs)	3.91–4.39 (4.10 ± 0.13)	4.17–4.56 (4.35 ± 0.10)	4–4.26 (4.14 ± 0.07)
Duration of Vocalization	570–1524 (1052 ± 307)	549–4335 (1063 ± 660)	481–4926 (1464 ± 1055)
Duration of Each Note	13–20 (16 ± 2, n = 109)	7–20 (15 ± 2, n = 340)	10–22 (17 ± 2, n = 160)
Interval Between Vocalizations	1402–6722 (4245 ± 1526)	926–9563 (2460 ± 1786)	1807–8039 (3727 ± 2176)
Interval Between Notes	103–166 (128 ± 14)	119–230 (163 ± 19)	95–245 (150 ± 22)