Bioacoustics of Pseudopaludicola ibisoroca

Advertisement call. —We analyzed 560 notes of six specimens of Pseudopaludicola ibisoroca sp. nov. ( Table 6 ). A typical advertisement call of the new species ( Fig. 10 ) consists of series of 12–287 notes with 3–12 concatenated pulses per note. Duration of each pulse varies from 1 to 8 ms (mean ¼ 3.0 ± 0.1 ms). Series duration varies from 2.5 to 59.8 s (mean ¼ 23.5 ± 15.1 s ). Series of notes are emitted at irregular intervals from 2.7 to 179.8 s (mean ¼ 91.6 ± 60.1 s ). Duration of each note varies from 25 to 50 ms (mean ¼ 34 ± 4 ms), internote interval from 67 to 585 ms (mean ¼ 115 ± 41 ms), and the mean rate of notes per minute from 263.3 to 466.9 (mean ¼ 356.3 ± 64.1). Mean frequency band ranges from 2821.7 (± 193.9) Hz to 5373.8 (± 336.6) Hz. Dominant frequency varies from 3617.6 to 4651.2 Hz (mean ¼ 4167.7 ± 287.5 Hz). Karyotype description. —The chromosomal complement of Pseudopaludicola ibisoroca sp. nov. is 2n ¼ 18, constituting four metacentric pairs (1, 2, 5, and 6), three submetacentric pairs (3, 4, and 9) and two telocentric pairs (7 and 8; Fig. 11A ). In all individuals analyzed, the nucleolar organizer region (NOR) was detected in the pericentromeric region of the short arm of Chromosome 3 ( Fig. 11B ). In some metaphases, this region could be observed as a secondary constriction after Giemsa staining. Centromeric regions were found in all chromosomes after C-banding method and slightly marked heterochromatic blocks were also observed in the telomeric regions of some chromosome pairs. No interstitial heterochromatic block was detected on the long arm of Pair 2, even though variations in exposure time with barium hydroxide caustic treatments were tested ( Fig. 11C ). Heteromorphic sexual chromosomes were not observed.

Etymology. —The specific epithet— ibisoroca —is a noun in apposition, resulting from a transliteration of Tupi– Guarani, a language family that comprises many different dialects spoken by South American indigenous people. It is formed by the words ‘‘yby’’ (or ‘‘yvy’’ ¼ earth, ground) and ‘‘sorok’’ (¼ crevice, crack), which together mean ravine or gully. Transliteration to modern Portuguese resulted in the words ‘‘boçoroca’’ or ‘‘voçoroca’’—large gully erosions. In short, a gully erosion ‘‘indicates that the soil is beyond its capacity to cope with the land use or the management practices’’ ( Alt et al. 2009:111 ). By coining the nomina ibisoroca , we intend to call attention to not only the fact that the topotypical population of our new species inhabits a highly impacted site, but also the urgent need for catchment conservation programs in the Neotropics, as previously suggested by Wantzen (2006) . We are particularly concerned about the situation in the Upper Araguaia headwaters, largely converted into agricultural and grazing lands without adequate soil conservation measures, which has already resulted in almost 200 places where gully erosion has been identified (see Filizola et al. 2011 ).

Geographic distribution. — Pseudopaludicola ibisoroca sp. nov. is currently known from its type locality, in southeastern state of Mato Grosso , and from Mineiros, Goiás ( Kopp et al. 2010 ), both in midwestern Brazil ( Fig. 6 ). Kopp et al. (2010) recorded the sympatric occurrence of three species of Pseudopaludicola . One of them, referred to by those authors as ‘‘ Pseudopaludicola aff. falcipes , ’’ is here recognized as belonging to our P. ibisoroca sp. nov. Based in bioacoustical analyses of calls provided by K. Kopp, this species occurs at Parque Nacional das Emas, together with P. saltica and P. ternetzi . (B) adult female (UFMT 6520). A color version of this figure is available on-line.

Diagnosis. — Pseudopaludicola ibisoroca sp. nov. is assigned to the genus Pseudopaludicola based on the presence of a hypertrophied antebrachial tubercle ( Lynch 1989 ), posterolateral process of the hyoid outlined and epicoracoid cartilages slightly overlapped ( Lobo 1995 ). The new taxon is diagnosed by the following combination of characters: (1) SVL ¼ 12.8–15.6 mm in males and 15.5–17.6 mm in females; (2) absence of either T-shaped terminal phalanges or expanded toe tips (disks or pads); (3) short hindlimbs, with tibiotarsal articulation only reaching the eye; (4) karyotype, 2n ¼ 18; (5) advertisement call composed of series of 12–287 notes with 3–12 concatenated pulses per note, note with duration of 25–50 ms; (6) dominant frequency of advertisement call 3617.6–4651.2 Hz. Trait Holotype Males ( n ¼ 14) Females ( n ¼ 6) SVL 13.07 14.2 ± 0.8 (12.8–15.6) 16.5 ± 0.8 (15.5–17.6) HL 5.78 5.6 ± 0.5 (5.0–6.7) 6.4 ± 0.6 (5.4–7.0) HW 4.86 4.9 ± 0.2 (4.5–5.5) 5.7 ± 0.3 (5.4–6.2) IOD 0.87 1.1 ± 0.1 (0.9–1.4) 1.2 ± 0.9 (1.1–1.4) ED 1.33 1.6 ± 0.9 (1.2–1.6) 1.6 ± 0.1 (1.6–1.7) END 1.03 1.1 ± 0.1 (1.0–1.3) 1.3 ± 0.1 (1.1–1.4) IND 1.32 1.4 ± 0.1 (1.3–1.6) 1.6 ± 0.2 (1.4–1.9) HAL 4.01 4.2 ± 0.3 (3.8–4.8) 4.6 ± 0.2 (4.3–4.9) THL 6.04 6.5 ± 0.6 (5.1–7.1) 7.6 ± 0.3 (7.3–8.2) TL 7.08 7.4 ± 0.4 (6.7–8.0) 8.6 ± 0.3 (8.3–9.0) TAL 4.05 4.2 ± 0.3 (3.5–4.5) 4.8 ± 0.2 (4.5–5.1) FL 7.70 8.4 ± 0.6 (7.0–9.4) 9.6 ± 0.4 (9.1–10.1) Comparisons. — Pseudopaludicola ibisoroca sp. nov. can be distinguished from all congeneric species (characters of comparative species in parentheses) belonging to the P. pusilla group ( P. boliƲiana , P. ceratophŋes , P. llanera , P. motorzinho , and P. pusilla ) by the absence of either Tshaped terminal phalanges or expanded toe tips. From Pseudopaludicola species not assigned to any species group, the new species differs from P. ameghini , P. giarettai , and P. ternetzi by the smaller body size ( P. ameghini , 16.3–18.6 mm SVL in males and 18.5–22.7 mm SVL in females; Haddad and Cardoso 1987 ; Pansonato et al. 2013 ; P. giarettai , 16.2–18.0 mm SVL in males; Carvalho 2012 ; P. ternetzi, SVL of males 16.0– 18.6 mm ; SVL of females 16.0– 22.2 mm ; Lobo 1996 ); from P. falcipes , by the presence of a complete abdominal fold (abdominal fold interrupted or absent; Lobo 1996 ; Lavilla and Cei 2001 ); from P. mineira , by head longer than wide (head as long as wide; Pereira and Nascimento 2004 ); from P. murundu and P. saltica , by the shorter hindlimbs, with tibio–tarsal articulation reaching the nostrils (presence of very long hindlimbs, with tibio–tarsal articulation reaching beyond the tip of snout; Toledo et al. 2010 ; Pansonato et al. 2013 ). The appearance of the vocal sac of male Pseudopaludicola ibisoroca sp. nov. —light cream—distinguishes the new species from P. atragula and P. facureae (whitish, with dark reticulation; Pansonato et al. 2014a ), and from P. murundu (uniformly dark; Toledo et al. 2010 ). Presently, 5 out of 14 species without T-shaped terminal phalanges cannot be morphologically distinguished from Pseudopaludicola ibisoroca sp. nov. : P. canga , P. hŋleaustralis , P. mŋstacalis , P. parnaiba , and P. pocoto . The advertisement call structure distinguishes the new species from these 5 species, however, as well as from other 11 congeners for which call descriptions are also available ( P. ameghini , P. atragula , P. boliƲiana , P. facureae , P. falcipes , P. giarettai , P. mineira , P. motorzinho , P. murundu , P. saltica , and P. ternetzi ). Parameter Voucher record Locality Air temp (°C) Notes per series Note rate/min Series duration (s) LH 40A–03 ( n ¼ 100) Alto Taquari (MT) 23.5 136 ± 139.5 (12–287) 290 ± 8.7 (283–300) 28 ± 29.1 (2.5–59.8) LH 40A–04 ( n ¼ 100) Alto Taquari (MT) 25.6 126.2 ± 74.7 (34–212) 363 ± 66.5 (263.3–399) 19.7 ± 10.2 (7.7–31.9) LH 40A–05 ( n ¼ 100) Alto Taquari (MT) 23.5 178 466.9 22.874 LH 40A–06 ( n ¼ 100) Alto Taquari (MT) 23.5 140.5 ± 130.8 (48–233) 372.3 ± 34.3 (347.9–396.6) 23.7 ± 23.3 (7.3–40.2) LH 40A–07 ( n ¼ 100) Alto Taquari (MT) 24.4 152 430.7 21.2 LH 730 ( n ¼ 60) Mineiros (GO) 22.6 146 ± 58 (105–187) 333.3 ± 46.3 (300.6–366.1) 25.8 ± 6.8 (20.9–30.6) Mean ( n ¼ 500) 139.7 ± 80.9 (12–287) 356.3 ± 64.1 (263.3–466.9) 23.5 ± 15.1 (2.5–59.8) The new species differs from P. canga , P. facureae , P. giarettai , P. hŋleaustralis , and P. parnaiba by having note structure with concatenated pulses (nonpulsed note structure in all comparative species; Giaretta and Kokubum 2003 ; Carvalho 2012 ; Pansonato et al. 2012 ; Andrade and Carvalho 2013 ; Roberto et al. 2013 ; Pansonato et al. 2014a ). It differs from P. ameghini , P. atragula , P. falcipes , P. mineira , P. murundu , P. pocoto , P. saltica , and P. ternetzi by having a call note with concatenated pulses (note with nonconcatenated pulses; 3–6 pulses per note, Pansonato et al. 2013 ; 9–36 pulses per note, Pansonato et al. 2014a ; 2 pulses per note, Haddad and Cardoso 1987 ; 2 pulses per note, Pereira and Nascimento 2004 ; 2–6 pulses per note, Toledo et al. 2010 , and Pansonato et al. 2014b ; 2–3 pulses per note, Magalhães et al. 2014 ; 1–4 pulses per note, Pansonato et al. 2013 ; 3–6 pulses per note in populations from Minas Gerais and São Paulo , Cardozo and Toledo 2013 ) and lower dominant frequency ( P. murundu 4875–6370 Hz, and P. pocoto 5168– 6374 Hz; Magalhães et al. 2014 ; Pansonato et al. 2014b ). Amongst species for which notes with concatenated pulses have been described, Pseudopaludicola ibisoroca sp. nov. differs from P. mŋstacalis by having a smaller number of pulses per note (12–20 pulses per note; Pansonato et al. 2013 , 2014b ) and lower mean dominant frequency (4887.4 ± 149.5 Hz; Pansonato et al. 2013 , 2014b ); from P. boliƲiana by larger number of notes per series (4–5 notes; Duré et al. 2004 ), longer internote intervals (2–14 ms), lower rate of notes per minute (293.6–1463.4), and lower mean dominant frequency (4581.1 ± 202.4 Hz; present study); from P. motorzinho by larger number of pulses per note (2–6 pulses), longer duration of each note (5–25 ms), and lower mean dominant frequency (5071 ± 242 Hz). The number of chromosomes (2n ¼ 18) separates Pseudopaludicola ibisoroca sp. nov. , from P. mŋstacalis (2n ¼ 16); P. ameghini and P. ternetzi (2n ¼ 20); and P. falcipes , P. mineira , P. motorzinho , P. murundu , and P. saltica (2n ¼ 22; Duarte et al. 2010 ; Fávero et al. 2011 ; Veiga-Menoncello et al. 2014 ).