Ranitomeya aquamarina Mônico, Koch, Dayrell, Moravec & Lima, 2025, sp. nov.

Ranitomeya aquamarina sp. nov. Figs 2, 3, 4, 6, 7, 8, 10, Tables 2, 3, 4 Chresonymy. Ranitomeya sp. Envira – Twomey et al. (2023); Ranitomeya aff. sirensis – Lima et al. (2024). Vernacular names. Suggested English name: Metallic poison frog. Suggested Spanish name: Rana venenosa metálica. Suggested Portuguese name: Rãzinha-venenosa-metalizada. Type material. Holotype. • INPA-H 47568 (field number APL 24805; Fig. 2), adult male collected by Alexander Tamanini Mônico and Albertina Pimentel Lima on 15 March 2024, from RAPELD sampling module of the Eiru River, tributary of the Juruá River, municipality of Eirunepé, Amazonas state, Brazil (6°47'04.9"S, 69°52'00.3"W, WGS 84, 137 m elevation). Paratypes. Twelve adult specimens (7 males and 5 females), same locality as holotype • one male [INPA-H 47561; field number APL 24481] collected on 26 February 2023 by A. P. Lima • 3 males [INPA-H 47563, INPA-H 47564 and MPEG 45220; field numbers APL 24765, 24766 and 24768, respectively] and 3 females [INPA-H 47562, INPA-H 47565 and MPEG 45221; field numbers APL 24764, 247667 and 24769, respectively] collected on 24 March 2023 by A. P. Lima and J. Dayrell • 3 males [INPA-H 47566, MPEG 45223 and INPA-H 47570; field numbers APL 24800, 24808 and 24809, respectively] and 2 females [INPA-H 47569 and MPEG 45222; field numbers APL 24806 and 24807, respectively) collected on 14–15 March 2024 by A. T. Mônico and A. P. Lima. Generic placement. We assign the new species to Ranitomeya, based on the phylogenetic placement (Fig. 1) and the following external characteristics: coloration is bright and aposematic, finger I is greatly reduced and shorter than finger II, finger discs two and four are greatly expanded, dorsal skin texture is smooth (to shagreen), and toe webbing is absent (see Brown et al. 2011; Kahn et al. 2016). Characterization. This new species of Ranitomeya is characterized by the following combination of characters: (1) dorsal color jet black with three parallel stripes metallic light yellowish green to metallic light turquoise-green, mid-dorsal stripe extending from between eyes to slightly before the vent, dorsolateral stripes extending from the snout to the groin, where they become medium sulfur yellow; (2) venter jet black with metallic olive-yellow to metallic light yellowish green reticulations on belly, and gular region metallic light yellowish green to olive-yellow; ventrolateral stripes light yellowish green; extending from through the loreal region, to the thighs integrating into the ventral reticulate pattern, becoming medium sulfur yellow on the arms; (3) limbs medium metallic chrome orange with dark carmine spotting, presence of a conspicuous sulfur yellow spot on the dorsal surface of the thighs, forming an ‘ ocellus’ like pattern; (4) dorsal skin shagreen to granular, and smooth on head; (5) gular and ventral skin shagreen to granular; (6) limbs smooth to shagreen; (7) SVL in adult males of 15.4–17.7 mm (n = 8) and in females of 17.3–18.5 mm (n = 5); (8) sexual dimorphism, females with greater SVL, BW and KK; presence of vocal slits in males, located near jaw articulation; (9) head width 0.8–1.0 × body width; (10) head width 1.1–1.2 × larger than head length; (11) head width 31–34 % of SVL; (12) snout moderately long (SL 36–42 % of HL), rounded in dorsal view and rounded to protruding in lateral view; (13) canthus rostralis rounded, loreal region flat; (14) nostril directed frontolaterally at the angle of the snout, internarial distance 33–39 % of head width; (15) tympanum visible, tympanic membrane poorly differentiated, tympanum diameter 38–48 % of eye diameter; (16) tongue ovoid, attached anteriorly; (17) dentigerous processes of vomers absent; (18) choanae ovoid and small, located marginally in the maxilla; (19) hand 24–28 % of SVL, arm 25–30 % of SVL; (20) fingers III> IV> II> I, Finger I 58–68 % of Finger II, finger discs rounded on Finger I, and expanded and truncate on fingers III and IV; (21) thenar tubercle elliptical, palmar tubercle large and ovoid; (22) proximal subarticular tubercles ovoid, present in each finger; distal subarticular tubercle present only on Finger III; (23) knee-knee distance 80–84 % of SVL, femur 94–98 % of tibia; (24) toes IV> III> V> II> I, Toe I 48–64 % of Toe II, finger discs not expanded and rounded on Finger I to elliptical on toes III and IV and truncate on Finger V; (25) outer metatarsal tubercle ovoid, poorly visible; inner metatarsal tubercle elliptical; (26) proximal subarticular tubercles ovoid on all toes, distal subarticular tubercles on toes III – V; (27) advertisement call with 21–45 notes and average call duration of 647–1,424 ms, note rate (28–36 notes / s) and dominant frequency of 4,996 –6,288 Hz; and (28) tadpole head translucent in life, and posterior tooth rows P- 1> P- 2> P- 3. Differential diagnosis. External morphology. The new species differs from all currently recognized Ranitomeya species (R. amazonica, R. benedicta, R. cyanovittata, R. defleri, R. fantastica, R. flavovittata, R. imitator, R. reticulata, R. sirensis, R. summersi, R. toraro, R. uakarii, R. vanzolinii, R. variabilis, R. ventrimaculata, and R. yavaricola) by its unique coloration (light yellowish green to light metallic turquoise-green dorsal stripe pattern, medium metallic chrome orange limbs with dark carmine spotting, and conspicuous sulfur yellow ocellus-like spot on the dorsal surface of the thighs). Ranitomeya aquamarina sp. nov. is generally most similar to R. cyanovittata and R. yavaricola but it can be easily distinguished from R. cyanovittata by light yellowish green to light metallic turquoise green dorsal stripes and medium metallic chrome orange limbs with dark carmine spotting (dorsal stripes turquoise blue, limbs with bluish reticulation and black spots; Pérez-Peña et al. 2010) and from R. yavaricola by light yellowish green to light metallic turquoise green dorsal stripes with no or only minor breaks and by dark carmine spotting on the limbs (dorsal stripes sage color, formed by points, that can become dashes, limbs solid bronze; Pérez-Peña et al. 2010). In addition, Ranitomeya aquamarina sp. nov. is distinguished by its smaller male SVL (15.4–17.7 mm) from R. fantastica (~ 20 mm; Boulenger 1884), R. imitator (~ 19 mm; Schulte 1986) and R. summersi (17.5–19.5 mm; Brown et al. 2008); and larger than R. cyanovittata (13.8 mm; Pérez-Peña et al. 2010), R. sirensis (14.7–15.4 mm; Aichinger 1991), R. toraro (14.8–15.6 mm; Brown et al. 2011) and R. uakari (14.8–15.5 mm; Brown et al. 2006); by its larger female SVL (17.3–18.5 mm) from R. sirensis (16.8 mm; Aichinger 1991), R. toraro (16.2–16.7 mm; Brown et al. 2011), R. uakari (15.7–16.2 mm; Brown et al. 2006); R. yavaricola (16.7–16.8 mm; Pérez-Peña et al. 2010); by its greater female head width (5.7–5.9 mm) from R. cyanovittata (5.6 mm; Pérez-Peña et al. 2010), R. sirensis (5.4 mm; Aichinger 1991), R. toraro (5.0– 5.3 mm; Brown et al. 2011), R. uakarii (5.0– 5.2 mm; Brown et al. 2006), R. yavaricola (5.1–5.7 mm; Pérez-Peña et al. 2010); by its greater male head length (4.8–5.4 mm) from R. cyanovittata (3.6 mm; Pérez-Peña et al. 2010) and R. sirensis (3.0– 3.8 mm; Aichinger 1991), but smaller than R. imitator (~ 6 mm) and R. yavaricola (5.5–6.6 mm; Pérez-Peña et al. 2010); by its smaller female head length (5.1–5.2 mm) from R. toraro (5.5 mm; Brown et al. 2011) and R. yavaricola (5.9–6.3 mm; Pérez-Peña et al. 2010) and larger than R. sirensis (4.0 mm; Aichinger 1991). Bioacoustics. The advertisement call of R. aquamarina sp. nov. is distinguished by its longer call duration (647–1,424 ms) from the call of R. amazonica (160–360 ms; Brown et al. 2011), R. benedicta (100–170 ms; Brown et al. 2008), R. defleri (410–620 ms; Twomey and Brown 2009), R. fantastica (180–320 ms; Brown et al. 2011), R. reticulata (180–290 ms; Brown et al. 2011), R. summersi (380–500 ms; Brown et al. 2008), R. uakarii (260–290 ms; Brown et al. 2006, Brown et al. 2011), R. vanzolinii (570–640 ms; Brown et al. 2011), R. variabilis (140–440 ms; Brown et al. 2011) and R. ventrimaculata (320–380 ms; Brown et al. 2011). Furthermore, it differs by its higher dominant frequency (4,996 –6,288 Hz) from the calls of R. benedicta (3,190 –4,240 Hz; Brown et al. 2008), R. fantastica (2,950 –3,790 Hz; Brown et al. 2011), R. reticulata (4,140 –4,480 Hz; Brown et al. 2011), R. summersi (2760–3220 Hz; Brown et al. 2008), R. uakarii (3,790 –4,130 Hz; Brown et al. 2006, Brown et al. 2011), and R. ventrimaculata (4190–4400 Hz; Brown et al. 2011); by its lower number of notes (21–45) from the calls of R. reticulata (48–94; Brown et al. 2011) and R. ventrimaculata (58–63; Brown et al. 2011); by greater number of notes from the calls of R. fantastica (10–13; Brown et al. 2011), R. summersi (14–16; Brown et al. 2008), R. uakarii (14–16; Brown et al. 2006, Brown et al. 2011), and R. vanzolinii (16–17; Brown et al. 2011); by its smaller note rate (28–36 notes / s) from the calls of R. amazonica (85–138 notes / s; Brown et al. 2011), R. defleri (94–104 notes / s; Twomey and Brown 2009), R. fantastica (41–57 notes / s; Brown et al. 2011), R. reticulata (270–382 notes / s; Brown et al. 2011), R. summersi (39–40 notes / s; Brown et al. 2008), R. uakarii (50–58 notes / s; Brown et al. 2006; Brown et al. 2011), R. variabilis (106–297 notes / s; Brown et al. 2011), and R. ventrimaculata (166–181 notes / s; Brown et al. 2011). The advertisement call of R. aquamarina sp. nov. is highly similar to the calls of all other species of the R. vanzolinii group, which have long-lasting trills, but it can still be distinguished from the call of R. vanzolinii, which has slightly lower note rate of 26–28 notes / s (Brown et al. 2011). On the other hand, based on the literature, the call of R. aquamarina sp. nov. is indistinguishable from the calls of R. flavovittata, R. imitator, R. sirensis, and R. yavaricola (Perez-Peña et al. 2010; Brown et al. 2011). There is no available information about minimu