A new species of rain frog (Anura: Strabomantidae: Pristimantis) from the Guiana Shield and amended diagnosis of P. ockendeni (Boulenger, 1912) Author Monico, Alexander Tamanini https://orcid.org/0000-0002-2965-8020 Programa de Pos-Graduacao em Biologia (Ecologia), Instituto Nacional de Pesquisas da Amazonia, Manaus, Amazonas, Brazil alexandermonico@hotmail.com Author Ferrao, Miqueias https://orcid.org/0000-0001-7035-8276 Museum of Comparative Zoology, Harvard University, Cambridge, Massachusetts, United States of America Author Chaparro, Juan Carlos Museo de Biodiversidad del Peru, Cusco, Peru & Museo de Historia Natural, Universidad Nacional de San Antonio Abad del Cusco, Cusco, Peru Author Fouquet, Antoine Laboratoire Evolution et Diversite Biologique, Universite Paul Sabatier, Toulouse, France Author Lima, Albertina Pimentel https://orcid.org/0000-0003-4586-5633 Programa de Pos-Graduacao em Biologia (Ecologia), Instituto Nacional de Pesquisas da Amazonia, Manaus, Amazonas, Brazil text Vertebrate Zoology 2022 2022-11-10 72 1035 1065 http://dx.doi.org/10.3897/vz.72.e90435 journal article http://dx.doi.org/10.3897/vz.72.e90435 2625-8498-72-1035 D0416380CB035C2AB3CF821DC5767D27 Pristimantis ockendeni (Boulenger, 1912) Figs 3 , 4 , 5 Hylodes ockendeni - Boulenger (1912) Eleutherodactylus ockendeni - Lynch (1996) Pristimantis ockendeni - Heinicke et al. (2007) , Hedges et al. (2008) , Padial et al. (2014) , Ocampo et al. (2016) , von May et al. (2017) , Villacampa et al. (2017) Syntypes. BMNH 1947.2.16.88, BMNH 1947.2.16.89 and BMNH 1947.2.16.90 (Fig. 3 ), collected on 07 May 1907 from La Union, Rio Huacamayo, Carabaya, southeastern Peru ( 13°31′58.3″S , 69°45′06.7″W ; 783 m elevation). Figure 3. Dorsal, ventral and lateral views of syntypes of Pristimantis ockendeni . A , B and C female, NHM 1947.2.16.88; D , E and F female, NHM 1947.2.16.89; and G , H and I male, NHM 1947.2.16.90. Photographs: Natural History Museum of London. Th e specimens are in a good state of preservation, allowing for an easy view, for example, of the dark bar between the eyes, of oblique black streak in front of and behind the eye, oblique brown bars on the tibia, supratympanic stripe and melanophores in ventral surface. We compared the newly collected individuals with the morphological diagnosis described by Boulenger (1912) and the syntypes of species (through high quality images made available by the Natural History Museum - London) to ensure that we are dealing with the same taxon. Moreover, the molecular analyses confirmed that our material is conspecific to a specimen (voucher RvM5_12) collected near the type locality (112 km linear distance) and made available by von May et al. (2017) . Our samples are distributed at altitudes ranging from 223 m (in Brazil) to 924 m (in Peru), range that includes the altitude of the type locality (783 m). The characters available in the species description are relatively vague. Boulenger (1912) defined the size of the species as 34 mm from snout to vent, based on the two female syntypes (NHM 1947.2.16.88 and NHM 1947.2.16.89). Boulenger might not have included the third syntype (NHM 1947.2.16.90) because he believed it was a juvenile individual, but our examination showed this specimen to be an adult male. We acknowledge that>100 km separates the type locality from the closest newly collected population that could corresponds to Pristimantis ockendeni . Therefore, on the sole basis of geographical distance and considering the megadiversity and the cryptic morphology of this clade we cannot completely reject the hypothesis that our populations in fact belong to another species than P. ockendeni . Nevertheless, four other nominal species of the Pristimantis unistrigatus species group are known to occur in the area [i.e. P. altamazonicus (Barbour & Dunn, 1921), P. carvalhoi (Lutz, 1952), P. divnae Lehr & von May, 2009, and P. ventrimarmoratus (Boulenger, 1912); Duellman 2005 ; Villacampa et al. 2017 ] and one undescribed (" Pristimantis sp. 3" sensu Villacampa et al. 2017 ). However, all of them have distinctive features on groin (yellow, orange or red marks) or belly (black marble) that readily distinguishes them from P. ockendeni . Also, the main lineages of the P. unistrigatus species group related to P. ockendeni [i.e., P. matidiktyo , P. daquilemai Brito-Zabata, Reyes-Puig, Cisneros-Heredia, Zumel & Ron, 2021, and P. delius (Duellman & Mendelson, 1995)], and possible any undescribed species related to them, can be easily distinguished from P. ockendeni . For example, P. matidiktyo differs by the dorsum without any marks and the presence of a small tubercle on the upper eyelid, P. daquilemai differs by its flanks densely tuberculated and the presence of a prominent rostral papilla at tip of snout, and P. delius is distinguished by the snout acutely rounded in dorsal view and the absence of dentigerous processes of vomers. Finally, the characters described by Boulenger (1912) , although vague, but completed by the examination of the syntypes (see below), strongly suggests that the newly collected specimens are conspecific to P. ockendeni . Referred material. Available in Appendix 1. Amended diagnosis. The species is characterized by the combination of the following characters, based on the description of Boulenger (1912) with additions to this study, obtained through examination of the syntypes (Fig. 3 ) and to the material recently collected (Fig. 4 ): (1) dorsal skin smooth to shagreen, frequently with distinctly enlarged tubercles, with or without W-shaped on scapular region, a narrow light vertebral line may be present; (2) tympanum very indistinct, its length 30 to 44% of eye length, tympanic membrane and tympanic annulus visible but sometimes inconspicuous; with or without supratympanic stripe; (3) snout short and subacuminate in dorsal view, with moderately strong, curved canthus and very oblique, concave loreal region; (4) upper eyelid usually bearing tubercles; dark bar between the eyes, and oblique black streak in front of and behind the eye; cranial crests absent; (5) nostril near the tip of the snout; interorbital space hardly as broad as the upper eyelid; (6) tongue oval, entire or indistinctly nicked behind; (7) dentigerous processes of vomers in two oblique oval groups just behind the level of the choanae, clearly visible; (8) vocal slits present, vocal sac median to subgular; nuptial pads absent; (9) Finger I shorter than Finger II; fingers moderate, discs ovoid to expanded (widest on fingers III and IV); (10) fingers without lateral fringes; (11) three to four ulnar tubercles, ill defined; (12) tibia length 49-56% of SVL; (13) heel bearing one rounded tubercle; small tarsal tubercles, ovoid, poorly visible in fixed specimens; inner edge of tarsus with a short fold; (14) two feebly prominent metatarsal tubercles, being thenar tubercle ovoid to elliptical and small palmar tubercle ovoid; subarticular tubercles well developed but small; (15) toes without lateral fringes; scarcely a rudiment of web between them; (16) Toe I clearly smaller than Toe II, toes moderate, discs ovoid to expanded (widest on toes III to V); (17) dorsal coloration very variable; two or three oblique brown bars on the tibia; ventral surface smooth to slightly areolate, variable concentration of melanophores; and ventral region of the femur externally slightly areolate; (18) absence of spot on groin; (19) dichromatic iris in life, the lower part being coppery and the upper part cream; (20) SVL in adult males of 18.3-22.8 mm (n = 9; Table 4 ) and females of 30.4-30.6 mm (n = 2; Table 4 ); and (21) advertisement call with average call duration of 541 +/- 151 ms, inter-note interval of 44 +/- 5 ms (68 +/- 11 ms), minimum frequency of 2,046-2,610 Hz, maximum frequency of 2,964-3,641 Hz and dominant frequency of 2,519-3,143 Hz. Table 4. Morphometric measurements in millimeters of adults of Pristimantis guianensis sp. nov. and P. ockendeni . The measurement of the two P. ockendeni females correspond to the syntypes. Values express mean +/- standard deviation (range). Measurement abbreviations are listed in the Material and Methods.

Variables	Pristimantis guianensis sp. nov.			Pristimantis ockendeni
	Holotype	Males (n = 43)	Females (n = 13)	Males (n = 9)		Females (n = 2)
				Syntype	Newly collected (n = 8)
SVL	17.7	17.9 +/- 0.8 (16.2-20.7)	23.8 +/- 1.3 (21.4-25.7)	18.6	19.6 +/- 1.3 (18.4-22.8)	30.4-30.6
HW	6.4	6.5 +/- 0.4 (5.7-7.6)	8.6 +/- 0.5 (7.5-9.6)	6.8	7.0 +/- 0.5 (6.7-8.2)	10.4-10.7
HL	6.7	6.8 +/- 0.4 (5.9-7.9)	8.7 +/- 0.7 (7.6-10.0)	6.9	7.2 +/- 0.4 (6.7-8.3)	10.8-10.8
SL	2.9	3.0 +/- 0.2 (2.6-3.5)	4.1 +/- 0.2 (3.8-4.5)	2.9	3.2 +/- 0.3 (2.7-3.6)	4.4-4.6
IND	1.9	1.8 +/- 0.2 (1.5-2.2)	2.3 +/- 0.2 (1.9-2.5)	1.8	2.0 +/- 0.1 (1.8-2.2)	2.6-2.7
EN	2.1	2.1 +/- 0.1 (1.7-2.3)	2.9 +/- 0.1 (2.8-3.2)	1.8	2.2 +/- 0.3 (1.8-2.6)	3.3
IOD	3.6	2.1 +/- 0.1 (1.8-2.5)	2.8 +/- 0.2 (2.4-3.1)	2.3	2.4 +/- 0.2 (2.0-2.7)	3.8-3.9
ED	2.7	2.7 +/- 0.2 (2.3-3.0)	3.2 +/- 0.1 (3.1-3.4)	2.7	2.7 +/- 0.1 (2.6-3.0)	4.1-4.3
TD	0.8	0.8 +/- 0.1 (0.6-1.0)	1.0 +/- 0.1 (0.8-1.2)	0.9	1.0 +/- 0.1 (0.9-1.2)	1.9
UAL	4.7	4.7 +/- 0.3 (4.0-5.2)	6.4 +/- 0.3 (5.8-6.7)	4.9	5.2 +/- 0.4 (4.8-6.2)	6.5-7.7
FAL	4.6	4.4 +/- 0.2 (3.8-4.9)	5.5 +/- 0.8 (3.8-6.3)	4.2	4.4 +/- 0.4 (3.8-5.1)	5.2-5.3
HAND	4.5	4.3 +/- 0.3 (3.6-5.1)	5.4 +/- 0.4 (4.7-6.1)	5.0	5.3 +/- 0.5 (4.9-6.6)	6.3-4.5
HANDI	2.2	2.2 +/- 0.2 (1.8-2.9)	2.8 +/- 0.3 (2.2-3.2)	2.6	2.7 +/- 0.3 (2.4-3.4)	3.9-4.0
HANDII	3.0	2.8 +/- 0.3 (2.0-3.4)	3.5 +/- 0.5 (2.6-4.1)	3.2	3.5 +/- 0.3 (3.2-4.2)	5.6-5.8
HANDIV	3.5	3.7 +/- 0.2 (3.2-4.3)	4.7 +/- 0.3 (4.3-5.1)	4.1	4.3 +/- 0.4 (3.9-5.3)	7.0-7.3
WFD	0.8	0.8 +/- 0.1 (0.5-1.0)	1.0 +/- 0.1 (1.0-1.2)	0.8	0.8 +/- 0.1 (0.8-0.9)	1.9
THL	9.2	8.7 +/- 0.6 (7.1-10.4)	10.7 +/- 0.7 (10.0-12.0)	9.2	9.3 +/- 0.5 (8.7-10.5)	14.9-15.6
TL	9.6	9.3 +/- 0.5 (8.2-10.7)	11.5 +/- 0.6 (10.7-12.5)	10.1	10.2 +/- 0.6 (9.5-11.4)	16.1-16.2
TAL	5.6	5.2 +/- 0.3 (4.4-5.9)	6.6 +/- 0.5 (5.7-7.3)	5.0	5.2 +/- 0.4 (4.9-5.7)	6.8-7.8
FL	7.2	6.9 +/- 0.4 (5.8-7.8)	8.6 +/- 0.5 (7.9-9.5)	7.9	8.3 +/- 0.8 (7.5-10.1)	12.3-12.5
FLI	2.4	2.3 +/- 0.2 (2.0-2.6)	3.0 +/- 0.2 (2.7-3.3)	2.4	2.6 +/- 0.3 (2.4-3.2)	4.1-4.5
FLII	2.9	3.0 +/- 0.2 (2.7-3.5)	3.8 +/- 0.2 (3.6-4.2)	3.4	3.5 +/- 0.2 (3.3-4.0)	5.5-8.4
FLIII	4.5	4.5 +/- 0.2 (4.1-5.1)	5.7 +/- 0.3 (5.4-6.3)	5.1	5.4 +/- 0.5 (4.9-6.6)	8.4-8.9
FLV	5.7	5.6 +/- 0.4 (4.3-6.4)	7.4 +/- 0.3 (6.9-7.8)	6.3	6.6 +/- 0.7 (5.8-8.2)	9.9-10.8
WTD	0.8	0.8 +/- 0.1 (0.5-1.0)	1.1 +/- 0.1 (0.9-1.3)	0.8	0.9 +/- 0.1 (0.7-1.0)	1.7-1.9

Figure 4. Newly collected specimens of Pristimantis ockendeni preserved, in dorsal and ventral view, respectively. A and B INPA-H 43946; C and D INPA-H 43949; and E and F INPA-H 43948. Photographs: A.T. Monico . Additional comments about P. ockendeni morphology. Dorsal pattern of males is highly variable, showing three main patterns (n = 8 specimens): (i) coloration strongly delimited and different from sideview, with or without dark transverse stripes on dorsum (n = 4 specimens; Fig. 4A ; in life, Fig. 5A , 5B , 5D and 5F ); (ii) irregular dark markings present on dorsum (Fig. 4C ); and (iii) similar to the previous pattern, but lighter (Fig. E); mostly, interorbital region is covered by a dark band (n = 5 specimens). In addition, in some individual, W-shaped mark on scapular region present, even if not very evident (Fig. 4C ; Fig. 5E and 5G ). Ventral surface can have different shades, varying according to the concentration of melanophores: darker (Fig. 4B ), intermediary (Fig. 4D ) or lighter (Fig. 4F ). Ventral skin texture is smooth (arms and chest region) to areolate (especially in belly and on femur region). Figure 5. Pristimantis ockendeni . A INPA-H 43946 (SVL 20.1 mm); B INPA-H 43952 (SVL 18.9 mm); C INPA-H 43948 (SVL 19.4 mm); D INPA-H 43945 (SVL 19.0 mm); E INPA-H 43950 (SVL 18.4 mm); F INPA-H 43947 (SVL 18.8 mm); G INPA-H 43949 (SVL 19.6 mm) in dorsal view; and H INPA-H 43949 in ventral view. Photographs: A.T. Monico . Dorsal coloration of males in life is highly variable, from brown reddish to yellow greenish (Fig. 5A-5G ) with or without interorbital bars. We do not have information on females. Arm is light yellowish. The iris is dichromatic (dark copper metallic down part and cream to silver upper part. Ventral surface is cream translucent (in the belly) and gray translucent (in the pelvic region) with dark melanophores (Fig. 5H ). Advertisement call of Pristimantis ockendeni . We recorded 40 calls of seven males from the underwood vegetation of about 2 m above the ground (air temperatures 23-25°C; relative humidity 82-99). Descriptive statistics of call parameters are presented in Table 5 and voucher in Appendix 4. The advertisement call of Pristimantis ockendeni has a call duration of 541 +/- 151 ms (334-939 ms, n = 40 calls) and 4-8 notes (6.1 +/- 0.9, n = 243 notes) with note duration of 24-158 ms (41 +/- 31 ms). Calls with 6 and 7 notes were the most common arrangement (37.5% of recorded calls, n = 15, and 32.5% n = 13, respectively), followed by calls with 5 notes (25%, n = 10 calls), and rarely with 4 and 8 notes (2.5% each, n = 1). Inter-note intervals within calls average 62 +/- 11 ms (38-87 ms). The spectral structure of the note has average minimum frequency of 2,389 +/- 190 Hz (2,046-2,610 Hz), while average maximum frequency is 3,350 +/- 201 Hz (2,964-3,641 Hz), and the dominant frequency is 2,864 +/- 202 Hz (2,519-3,143 Hz) (Fig. 6A and 6B ). Table 5. Acoustic variables of the advertisement call of Pristimantis guianensis sp. nov. (n = 111 calls, 34 males) and Pristimantis ockendeni (n = 40 calls, 7 males). Values express mean +/- standard deviation (range).

Acoustic variables	P. guianensis sp. nov.	P. ockendeni
Call duration (ms)	232 +/- 42 (158-371)	540 +/- 150 (334-940)
Number of notes per call	4.5 +/- 0.7 (4-6)	6.1 +/- 0.9 (4-8)
Note duration (ms)	18 +/- 11 (5-89)	41 +/- 31 (27-71)
Inter-note interval (ms)	44 +/- 5 (14-56)	68 +/- 11 (38-87)
Minimum frequency (Hz)	3,210 +/- 152 (2,827-3,695)	2,389 +/- 190 (2,047-2,610)
Maximum frequency (Hz)	5,264 +/- 639 (4,333-6,688)	3,350 +/- 201 (2,965-3,504)
Dominant frequency (Hz)	3,970 +/- 179 (3,466-4,521)	2,864 +/- 203 (2,519-3,144)

Figure 6. Pristimantis ockendeni advertisement calls spectrograms and oscillograms with five and six notes, respectively. A INPA-H 43952 (FNJV 58769) and B INPA-H 43946 (FNJV 58764), air temperature 24.1°C.