Amazophrynella minuta ( Melin, 1941 )

Rojas, Rommel R., Fouquet, Antoine, Carvalho, Vinícius Tadeu De, Ron, Santiago, Chaparro, Juan Carlos, Vogt, Richard C., Ávila, Robson W., Farias, Izeni Pires, Gordo, Marcelo & Hrbek, Tomas, 2018, Redescription of the Amazonian tiny tree toad Amazophrynella minuta (Melin, 1941) (Anura: Bufonidae) from its type locality, Zootaxa 4482 (3), pp. 511-526 : 515-522

Amazophrynella minuta ( Melin, 1941)

Synonymy

Atelopus minutus: Melin (1941: 40, Brazil; Amazonas Taracuá)

Dendrophryniscus minutus: McDiarmid (1971: 39, in part)

Lectotype (designated herewithin). NaTURHISTORISka MUSEET, GöTEbORg, SWEdEN, NHMG 462, SVL 13.40, adUlT malE, cOllEcTEd aT TaRacUá (0.10°S, 68.46°W) 100 m a.S.l., AmaZONaS STaTE, BRaZIl bY DOUglaS MElIN ON 1924.

Paralectotypes ( FIgURE 4 ). NHMG 463, NHMG 465 (adUlT malES), NHMG 464 (adUlT fEmalE) cOllEcTEd aT THE SamE PlacE aS THE lEcTOTYPE.

Topotypical specimens. INPA –H 32721–34, adUlT malES aNd INPA –H 32735–40, adUlT fEmalES cOllEcTEd bY ROmmEl R. ROjaS aT THE SamE PlacE aS THE lEcTOTYPE ON AUgUST 19 aNd 20, 2013.

Diagnosis. A SPEcIES Of Amazophrynella WITH: (1) MEdIUm bOdY SIZE fOR THE gENUS (SEE TablE 1), adUlT fEmalES 15.0–19.0 mm SVL (N=11), adUlT malES 12.2–14.2 mm SVL (N=20); (2) SNOUT POINTEd IN laTERal VIEW; UPPER jaW, IN laTERal VIEW, PROTRUdINg bEYONd lOWER; (3) TYmPaNUm, VOcal Sac, PaROTId glaNd aNd cRaNIal cRESTS INcONSPIcUOUS; (4) TEXTURE Of dORSal SkIN HIgHlY gRaNUlaR; (5) abUNdaNT Small ROUNdEd (IN PaRT cONIcal) WaRTS PRESENT ON dORSal SURfacES Of fORElImbS aNd HINdlImbS; (6) TEXTURE Of VENTRal SkIN HIgHlY gRaNUlaR; (7) fINgERS SlENdER, baSallY WEbbEd; (8) fINgER I SHORTER THaN fINgER II; (9) fINgER III RElaTIVElY lONg (HAL/SVL 0.2–0.3 mm, N=31); (10) PalmaR TUbERclE EllIPTIcal; (11) SUPERNUmERaRY TUbERclES ROUNdEd; (12) lONg HINd lImbS (TAL/SVL 0.4–0.5, N=31); (13) TOES SlENdER, baSallY WEbbEd; (14) TOES lackINg laTERal fRINgES; (15) PlaNTaR SURfacES Of fEET bEaRINg ONE mETaTaRSal TUbERclE, THE INNER 2.0X laRgER THaN THE OUTER, OUTER SUbcONIcal; SUPERNUmERaRY PlaNTaR TUbERclES ROUNdEd; (16) IN lIfE, VENTER cOlORaTION YEllOW–ORaNgE WITH laRgE TO mEdIUm SIZE black blOTcHES ON VENTER.

Comparisons with other species. Amazophrynella minuta IS mOST SImIlaR TO A. amazonicola fROm WHIcH IT caN bE dISTINgUISHEd bY (cHaRacTERISTIcS Of cOmPaREd SPEcIES IN PaRENTHESES) abSENcE Of Small TRIaNgUlaR PROTRUSION aT THE TIP Of THE SNOUT; TEXTURE Of dORSal SkIN HIgHlY gRaNUlaR (gRaNUlaR); PalmaR TUbERclE EllIPTIcal (ROUNdEd). FROm A. matses bY SNOUT POINTEd IN laTERal VIEW; TEXTURE Of dORSal SkIN HIgHlY gRaNUlaR (SPIcUlaTE); VENTER cOlORaTION YEllOW–ORaNgE (PalE YEllOW; FIgURE 5A VS. 5C). FROm A. javierbustamantei bY TEXTURE Of dORSal SkIN HIgHlY gRaNUlaR (TUbERcUlaTE); PalmaR TUbERclE EllIPTIcal (ROUNdEd); THROaT aNd cHEST cOlORaTION lIgHT bROWN (gRaYISH cREam); laRgE blOTcHES ON VENTER (Small POINTS). FROm A. siona bY SNOUT PROfIlE POINTEd (acUTE); WaRTS ON dORSUm (gRaNUlES); TEXTURE Of dORSal SkIN HIgHlY gRaNUlaR (fINElY gRaNUlaR). FROm A. moisesii bY SNOUT PROfIlE POINTEd (acUmINaTE); TEXTURE Of dORSal SkIN HIgHlY gRaNUlaR (TUbERcUlaTE); laRgE blOTcHES ON VENTER (TINY POINTS). FROm A. bokermanni , A. manaos , A. vote , A. xinguensis aNd A. manaos THE maIN dIffERENcE IS IN VENTER cOlORaTION, YEllOWISH–ORaNgE (WHITE IN A. manaos , A. bokermanni aNd A. teko , REd bROWN IN A. vote , bROWN IN A. xinguensis ; FIgURE 5A VS. 5F–J); FI <FII (VS. FI> FII IN A. bokermanni , aNd FI ≥ FII IN A. xinguensis ).

Redescription. BOdY SlENdER, SlIgHTlY ENlaRgEd POSTERIORlY. SEXUal dImORPHISm ObSERVEd IN SVL, WITH 12.2– 14.7 mm (13.6 ± 0.6 mm, N=20, TablE 4) IN adUlT malES aNd 14.5–19.4 mm (17.5 ± 1.5 mm, N=11) IN adUlT fEmalES. HEad POINTEd, lONgER THaN WIdE: HL 4.6–6.8 mm (5.4 ± 0.5 mm), 36.0% Of SVL; HW 3.8–5.8 mm (4.6 ± 0.1 mm), 30.0% Of SVL. SNOUT PROfIlE POINTEd IN laTERal VIEW; SL 2.1–3.2 mm (2.5 ± 0.3 mm), 46.0% Of HL. Canthus rostralis STRaIgHT aNd lOREal REgION VERTIcal. NOSTRIlS PROTUbERaNT, clOSER TO SNOUT THaN TO EYES. IND 1.0– 1.5 mm (1.2 ± 0.1 mm), 27.0% Of HW. INTERORbITal aNd OccIPITal REgIONS flaT. TYmPaNIc mEmbRaNE aNd TYmPaNIc aNNUlUS NOT aPPaRENT. PaROTOId glaNdS NOT VISIblE. VOcal Sac NOT VISIblE IN malES. EYES PROmINENT. EYE dIamETER 1.2–2.0 mm (1.5 ± 0.2 mm), 29.0% Of HL. EYElId WITH Small TUbERclES ON bORdERS. Choanae Small aNd cIRcUlaR. DORSal SkIN TEXTURE HIgHlY gRaNUlaR. Small ROUNdEd WaRTS (IN PaRT cONIcal) ON dORSOlaTERal aNd laTERal SURfacES POSTERIOR TO EYE, ON POSTERIOR dORSUm, aNd ON dORSal SURfacES Of ENTIRE aRm. TEXTURE Of gUlaR REgION, cHEST aNd bEllY HIgHlY gRaNUlaR. FORElImbS SlENdER. FOREaRmS RObUST, ESPEcIallY IN malES. UAL 3.5–5.5 mm (4.4 ± 0.7 mm); 29.3% Of SVL. FINgERS SlENdER. HAL 2.4–4.5 mm (3.1 ± 0.5 mm); 70.0% Of UAL. EdgES Of fORElImbS WITH ScaTTEREd gRaNUlES, IN dORSal aNd VENTRal VIEW. FINgERS baSallY WEbbEd. RElaTIVE lENgTH Of fINgERS: I <II <IV <III. FIRST fINgER SHORT, THIRd TWO TImES THE SIZE Of THE SEcONd, fOURTH laRgER THaN THE fIRST aNd SEcONd. LaRgE EllIPTIcal PalmaR TUbERclE. SUPERNUmERaRY TUbERclES ROUNdEd. THENaR TUbERclE abSENT. TIP Of fINgERS UNEXPaNdEd. NUPTIal Pad NOT EVIdENT. HINd lImbS SlENdER. VENTRal aNd laTERal SURfacES Of fORElImbS gRaNUlaR. THL 6.3–10.0 mm (7.6 ± 0.1 mm), 50.0% Of SVL. TAL 7.4–10.0 mm (7.4 ± 1.0 mm); 49.4% Of SVL. TL 3.7–6.7 mm (4.7 ± 0.8 mm); 32.0% Of SVL. FL 4.2–8.0 mm (5.5 ± 0.9 mm); 71.1% Of THL. ClOacal OPENINg SlIgHTlY abOVE mId–lEVEl Of THIgHS. GROUPINg Of bROWNISH–YEllOW gRaNUlES fROm THE HIddEN SURfacE Of THE THIgHS TO THE SHaNk. BaSal WEbbINg ON fOOT. TOES lackINg laTERal fRINgES. RElaTIVE lENgTH Of TOES: I <II <III <V <IV. FIRST TOE VERY SHORT; SEcONd Half THE SIZE Of THE THIRd. EllIPTIcal INNER mETaTaRSal TUbERclE PRESENT. SUbaRTIcUlaR TUbERclES VISIblE, mORE PROTRUdINg aNd SWOllEN IN fEmalES THaN malES. FOOT SlENdER. TIPS Of TOES UNEXPaNdEd.

Variation. VaRIaTION IN mEaSUREmENTS IS PRESENTEd IN TablE 1. SPEcImENS fROm JaPURa RIVER (INPA–H 32731, INPA–H 32724, INPA–H 32734) aRE lONgER (SL abOUT 1.0 mm) THaN INdIVIdUalS fROm THE TYPE lOcalITY. SOmE INdIVIdUalS fROm SÃO GabRIEl da CacHOEIRa PRESENT RElaTIVElY fEW WaRTS ON dORSal SURfacE (INPA–H32731, INPA–H 32724 aNd INPA–H 32734). MOTTlEd WaRTS dISSEmINaTEd ON cHEST aNd bEllY aRE fOUNd IN SPEcImENS INPA–H32731 (SÃO GabRIEl da CacHOEIRa) aNd INPA–35496 (JaPURa RIVER). SOmE SPEcImENS fROm THE TYPE lOcalITY (INPA–H 32728, INPA–H 32735) aNd fROm THE JaPURa RIVER (INPA–H 35512), PRESENT lOWER abUNdaNcE Of WaRTS ON aRmS.

Coloration in life ( FIgURE 6 ). HEad bROWN. DORSUm REddISH–bROWN. FlaNkS lIgHT bROWN. DORSal SURfacES Of THE UPPER aRm aNd aRm REddISH–bROWN. HaNdS aNd fINgERS lIgHT bROWN, IN dORSal VIEW. INSERTION Of THE aRmS PRESENT YEllOW blOTcHES. DORSal SURfacES Of THE THIgHS, TIbIa, TaRSUS aNd fEET REddISH–bROWN. VENTRal SURfacES Of UPPER aRm aNd aRm cREam. Palm lIgHT REd. VENTRal SURfacES Of THIgHS mOTTlEd cREam WITH Small black blOTcHES. THIgHS WITH a TRaNSVERSE laTERal black baR. POSTERIOR REgION Of THE THIgH aNd clOaca YEllOW, cOVEREd bY Small black blOTcHES. TaRSUS WITH TRaNSVERSE bROWN baRS. SOlE REddISH–bROWN. GUlaR REgION aNd cHEST gRaYISH–bROWN. VENTER cOlORaTION bETWEEN YEllOW aNd YEllOW–ORaNgE. VENTER cOVEREd bY laRgE TO mEdIUm SIZE black blOTcHES. IN VENTRal VIEW, SOmE SPEcImENS PRESENT YEllOW blOTcHES aT THE INSERTION Of THE aRmS. THE SPEcImENS INPA–H 32725 (TaRacUá) aNd INPA–H 35494 (JaPURa RIVER), dISPlaY YEllOW cOlORaTION WITH Small black blOTcHES ON POSTERIOR REgION Of THE THIgH NEaR THE clOaca. IRIS gOldEN aNd PUPIl black.

Color in preservative ( FIgURE 7 ). THE cOlOR IN PRESERVaTIVE fadEd. WE NOTEd THE PROgRESSIVE lOSS Of THE VENTRal cOlORaTION THaT bEcamE PalE YEllOW. THE YEllOW cOlORaTION ON aXIllaRY SURfacE dISaPPEaREd. IN VENTRal VIEW, THE cOlOR Of fINgERS aNd TOES lOST THEIR REd cOlOR aNd bEcamE cREam.

Distribution ( FIgURE 8 ). Amazophrynella minuta IS dISTRIbUTEd THROUgHOUT THE EaSTERN bORdER REgION Of THE AmaZONaS STaTE IN BRaZIl, a REgION alSO kNOWN aS “CabEÇa dO CacHORRO” (“DOg’S HEad”, ENglISH fREE TRaNSlaTION). THE SPEcIES IS fOUNd IN THE fOllOWINg lOcalITIES: TaRacUá (0.10°N, 68.46°W), SÃO GabRIEl da CacHOEIRa (0.16°S, 66.98°W), CUcUÍ (1.07°N, 66.88°W) aNd JaPURa RIVER SOUTH-EaST Of VIla BITTENcOURT (1.81°S, 68.98°W), aT ElEVaTIONS bETWEEN 90–105 m a.S.l. IN COlOmbIa IT IS REPORTEd IN THE DEPaRTmENT Of CaqUETá (0.92°N, 75.67°W) aNd VaUPéS (0.90°S, 69.67°W) ( LYNcH, 2006) aT ElEVaTIONS bETWEEN 100–200 m a.S.l. (AcOSTa– GalVIS, 2017). IN VENEZUEla, THE SPEcIES WaS REPORTEd fROm RaUdal dE DaNTO, RÍO CUaO (4.53°N, 67.18°W) AmaZONaS STaTE, aT ElEVaTION Of 105 m a.S.l. (ROjaS–RUNjaIc et al., 2013).

Ecology. WE fOUNd all INdIVIdUalS IN THE mORNINg, NEaR a bOdY Of WaTER. SPEcImENS WERE cOllEcTEd IN PRImaRY “ terra firme ” fOREST (“fIRm laNd” – NON–flOOdEd fOREST, ENglISH fREE TRaNSlaTION) SOmE IN THE lEaf lITTER aNd OTHERS amONg TREE ROOTS. SPEcImENS fROm SÃO GabRIEl da CacHOEIRa WERE cOllEcTEd IN a fRagmENT Of fOREST NEaR THE aIRPORT ; THE INdIVIdUalS WERE fOUNd aROUNd a STREam WITH abUNdaNT lEaf lITTER. AmPlEXUS IS aXIllaR ( FIgURE 9 ).

Phylogenetic analysis. THE cOmPlETE PHYlOgENETIc RElaTIONSHIPS Of Amazophrynella , THE PHYlOgENETIc POSITION Of A. minuta aNd gENETIc dISTaNcE bETWEEN SPEcIES Of Amazophrynella aRE REPORTEd IN ROjaS et al. (2018, FIgURE 1 aNd TablE 1).

Advertisement call ( FIgURE 10 ). THE cHaRacTERIZaTION Of THE adVERTISEmENT call Of Amazophrynella minuta WaS baSEd ON 14 callS fROm ONE INdIVIdUal fROm SÃO GabRIEl da CacHOEIRa (INPA–H 32730), SVL: 12.2 mm, REcORdEd bETWEEN 15:30–16:00 H. AIR TEmPERaTURE aT THE TImE Of REcORdINg VaRIEd bETWEEN 26.0 TO 27.0°C. THE call cONSISTEd Of a TRIllEd NOTE EmITTEd bETWEEN REgUlaR SIlENT INTERValS. NOTES Had aN UPWaRd amPlITUdE mOdUlaTION, REacHINg THEIR maXImUm INTENSITY NEaR THE mIddlE Of THE NOTE. NOTE dURaTION RaNgEd bETWEEN 0.310 aNd 0.108 S (0.223 ± 0.068 S). NUmbER Of PUlSES PER NOTE RaNgEd fROm 18 TO 35 PUlSES/NOTE (26.286 ± 6.557 PUlSES/NOTE). THE INTER–NOTE INTERVal WaS 0.663 TO 1.050 S (0.827 ± 0.120 S). THE dOmINaNT fREqUENcY RaNgEd fROm 4242.790 TO 4562.011 HZ (4419.213 ± 125.642 HZ). THE fUNdamENTal fREqUENcY RaNgEd fROm 3201.010 TO 3788.520 HZ (3489.211 ± 235.791 HZ). THE RISE TImE RaNgEd fROm 0.045 TO 0.083 S (0.059 ± 0.015 S). NUmbER Of HaRmONIcS VaRIEd fROm 3 TO 5 (4.150 ± 0.587).

Osteology. A dETaIlEd REVIEW aNd dEScRIPTION Of THE SkElETON Of A. minuta WERE PROVIdEd bY McDIaRmId (1971). IN THE SamE PUblIcaTION, McDIaRmINd (1971) REPORTEd cHaRacTERS THaT cOUld bE TENTaTIVElY cONSIdEREd aS PUTaTIVE gENUS lEVEl SYNaPOmORPHIES (SEE FOUqUET et al., 2012b).

Figures

FIGURE 1. Terminology used in this paper to describe texture of dorsal skin in Amazophrynella. A) Tuberculate; B) granular; C) highly granular; D) finely granular; E) Spiculate. See Materials and Methods for character definition.

FIGURE 4. Lectotype (A = NHMG 462) and paralectotypes (B = NHMG 465, C = NHMG 463) of Amazophrynella minuta (Melin, 1941) from Taracuá, Rio Uaupés, Amazonas State, Brazil deposited at the Naturhistoriska Museet, Göteborg, Sweden. Additional pictures of the types are provided in Figure 3 -page 70 in Ávila et al. (2012). Photos by: Anders Larson.

FIGURE 5. Species of Amazophrynella. A) A. minuta; B) A. matses; C) A. amazonicola; D) A. javierbustamantei; E) A. siona; F) A. bokermanni; G) A. manaos; H) A. vote; I) A. xinguensis; J) A. teko; K) A. moisesii.

FIGURE 6. Morphological variation in life of Amazophrynella minuta (Melin, 1941) from type locality. A–F) adult males; G– I) adult females.

FIGURE 7. Morphological variation of preserved specimens of Amazophrynella minuta (Melin, 1941) from the type locality. A–C) adult females; D–F) adult males.

FIGURE 8. Geographic distribution of Amazophrynella minuta (Melin, 1941), triangle marks the type locality. Brazil, Amazonas state: 1) São Gabriel da Cachoeira; 2) Lago Jabo-Cucui; 3–4) Vila Bittencourt, Japura River. Colombia, Vaupés department: 5) estación biológica Cacaparu; 6) Santander; 7) Vaupés River; 8) Mitu; Amazonas department: 10) Restinga isla mariname; 11) La chorrera; Department of Caqueta:12) Cabanachagra; 13) Caqueta River. Venezuela; Amazonas state: 14) Raudal de Danto, Río Cuao.

FIGURE 9. Axillary amplexus between specimens of Amazophrynella minuta (Melin, 1941)

FIGURE 10. Advertisement call of Amazophrynella minuta (Melin, 1941) from São Gabriel da Cachoeira, Amazonas state, Brazil. A) Oscillogram and spectrogram visualizing three notes; B) Oscillogram and spectrogram visualizing one note.