Zoosyst. Evol. 98 (1) 2022, 77-85 | DOI 10.3897/zse.98.61064 ZN ET ih denen ra ci ase oeeh oe Se D> PENSOFT. Nites A NATURKUNDE BERLIN A new species of Phalotris (Serpentes, Colubridae, Elapomorphin1) from Paraguay Paul Smith!*, Jean-Paul Brouard*, Pier Cacciali*>* FAUNA Paraguay, Encarnacion, Paraguay Para La Tierra, Centro IDEAL, Mariscal Estigarribia 321, Pilar, Neembuci, Paraguay Guyra Paraguay, Ay. Cnel. Carlos Boveda, Parque Ecoldgico Capital Verde — Vifias Cué, Asuncion, Paraguay BR WN Instituto de Investigacion Biolégica del Paraguay, Del Escudo 1607, 1425 Asuncion, Paraguay http://zoobank. org/34A3908E-943 1-4B2F-A967-773F 5DIAEFOC Corresponding author: Paul Smith (faunaparaguay@gmail.com) Academic editor: Johannes Penner # Received 23 November 2020 # Accepted 21 February 2022 # Published 7 March 2022 Abstract A new species of Phalotris from the nasutus group, Phalotris shawnella sp. nov., is described. It can be distinguished from the other members of the group by having the following combination of characters: 1) fifth supralabial in contact with parietal, 2) vertebral stripe present, 3) yellowish nuchal collar (2 or 3 dorsal scales long), 4) dull reddish color of head, 5) broad, solidly or near solidly dark, lateral bands, 6) red-orange ventral scales lightly and irregularly spotted with black mainly on the posterior half of the body and 7) a bilobed, extremely asymmetrical hemipenis, with enlarged, curved, lateral spines. The species is only known from a recent specimen collected in the Cerrado zone of northeastern Paraguay at Rancho Laguna Blanca, San Pedro department, and two photographic re- cords of live specimens from this and an additional locality. Limited ecological data based on observations of a captive individual, and a wild record, are provided, and a conservation assessment is performed for this extremely limited range Paraguayan endemic snake. Key Words endemic, hemipenis, Phalotris nasutus, Phalotris shawnella sp. nov. Resumen Se presenta la descripcion de una nueva especie de Phalotris del grupo nasutus, Phalotris shawnella sp. nov. puede ser diferenciada de otros miembros del grupo por tener la siguiente combinacion de caracteres: 1) quinta supralabial en contacto con la parietal, 2) presen- cia de una estria vertebral oscura, 3) collar nucal amarillento (de 2 6 3 escamas de ancho), 4) coloracion rojiza en la cabeza, 5) ancha faja lateral muy oscura o bastante oscura, 6) escamas ventrales rojo-anaranjadas e irregularmente salpicadas de negro principalmente en la parte posterior del cuerpo, y 7) hemipenes bilobados, extremadamente asimétricos, con espinas laterales agrandadas y curvas. La especie se la conoce unicamente de un ejemplar colectado en el Cerrado en el noreste de Paraguay en el Rancho Laguna Blanca, depar- tamento de San Pedro, ademas de dos registros fotograficos de ejemplares vivos, uno de esta misma localidad y otro de una localidad adicional. Se proveen datos ecologicos limitados, en base a observaciones de un ejemplar en cautiverio, y otro en la naturaleza, asi como una propuesta de evaluacion del estado de conservacion para este endemismo de Paraguay de rango extremadamente limitado. Palabras claves endémico, hemipene, Phalotris nasutus, Phalotris shawnella sp. nov. Copyright Smith P et al. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. 78 Introduction The genus Phalotris Cope, 1862 is a group of small to medium-sized, semi-fossorial snakes, distributed largely in open areas of Brazil, Bolivia, Paraguay, Uruguay, and Argentina (Ferrarezzi 1993). Though Cope (1862) described the genus, it was treated as a synonym of Elapomorphus Wiegmann, 1843 by most authors for over a century, until its revalidation by Ferrarezzi (1993) who considered it a monophyletic group close to Apostolepis Cope, 1862. More recently, Grazziotin et al. (2012) using five mitochondrial and three nuclear gene sequences showed Phalotris as the most primitive genus within the Elapomorphini, although this conclusion was only weakly supported. The genus is poorly represented in museum collections, but 14 species are currently recognized separated into three species groups (Ferrarezzi 1993): the tricolor group of five species (Jansen and Kohler 2008), the bilineatus group with four species (Puorto and Ferrarezzi 1993; Cacciali and Cabral 2015) and the nasutus group which includes five species (Moura et al. 2013). Following Entiauspe-Neto et al. (2021) we do not recognize the recently-described P. cerradensis Silveira, 2020 of this latter group as a valid species. Two synapomorphies distinguish the nasutus group: a pointed snout with prominent rostral shield; and fusion between the second and third series of temporal plates (sometimes on only one side of the head) (Ferrarezzi 1993; Moura et al. 2013). The five known species all occur in the Cerrado region of central South America: Phalotris concolor Ferrarezzi, 1993, Phalotris labiomaculatus Lema, 2002, Phalotris lativittatus Ferrarezzi, 1993, Phalotris nasutus (Gomes, 1915), and Phalotris nigrilatus Ferrarezzi, 1993. The only species of the nasutus group currently recorded from Paraguay is the endangered endemic P. nigrilatus. This species was described from a single female specimen (FML 709) collected at “Carumbé”, in the Paraguayan department of San Pedro, in 1973. The redescription of this species, including a description of the hemipenes, by Cacciali et al. (2007), was based on two further specimens (MNHN[M] 89 and 91) from “Primavera”, also San Pedro department (as the holotype), that were collected in 1957. Subsequently, additional specimens of P. nigrilatus that had been collected at the latter locality between 1954 and 1959 (NHM 1955.1.5.99, 1955.1.6.2—3, 1956.1.3.48-51, 1956.1.16.39-40, 1958.1.2.31, 1960.1.3.5-8, 1962.110) were also located (Cacciali et al. 2016). Cacciali et al. (2020) summarized the morphological data of these specimens, providing images of the first live specimen and discussing variation in pholidosis of the species. During field work at Rancho Laguna Blanca (San Pedro department, northeastern Paraguay) (Fig. 1) two specimens of a Phalotris nasutus group snake were captured, that exhibited intermediate characters between P. nigrilatus and P. lativittatus (the latter not previously recorded in Paraguay). With the photographing of zse.pensoft.net Smith, P. et al.: A new species of Phalotris from Paraguay -62.000 -60.000 -58.000 -56.000 -54.000 ———— TT Bolivia -20.000 000°02- _-24.000 -22.000 000'zz- 000'r2- -26.000_ a00'92- 000°e2- J I — -62.000 -60.000 -58.000 -56.000 -54.000 Figure 1. Known localities for Phalotris shawnella sp. nov. in San Pedro department, Paraguay Square: type locality. Circle: additional locality at Colonia Volendam. an additional specimen at a second locality (Colonia Volendam, San Pedro department) we undertook an extensive revision of specimens and the literature, and it became apparent that the differences were consistent and clear enough to indicate species level differentiation. Here we describe this as a new species of Phalotris of the nasutus group. Materials and methods Measurements of cephalic scales were taken on the left side of the body with dial callipers (accurate to 0.1 mm) and body lengths were measured with millimeter tape. Body lengths include snout-vent length (SVL) and tail length (TL). Descriptions of coloration are provided for live and fixed specimens. Ventral scale counts follow Dowling (1951). Dorsal scale counts and terminology follow Peters (1964), recording reduction. For supralabial counts, numbers in parentheses are those scales that contact the orbit and, likewise for infralabial counts, the numbers in parentheses are the scales in contact with the chin shields. First and second rows of temporals were counted. Paired structures are presented in right/ left orientation. The right hemipenis of the specimen was everted directly after euthanizing, and hemipenial terminology follows Zaher (1999). We follow Ferrarezzi (1993) for the designation of the groups. Behavioral data were collected from observations on a specimen kept briefly in captivity. Geographic and morphological data used _ for comparisons with other species within the nasutus group were extracted from Ferrarezzi (1993) for P. nasutus, Ferrarezzi (1993) and Silveira Vasconcelos and Gomes dos Santos (2009) for P. /ativittatus, Moura Zoosyst. Evol. 98 (1) 2022, 77-85 et al. (2013) for P. concolor, and Hamdan et al. (2013) for P. labiomaculatus. A list of examined specimens of P. nigrilatus and P. multipunctatus is provided in Appendix 1. Museum codes in the appendix are as follows: NHM Natural History Museum, London, UK; CZPLT Coleccién Zoologica Para La Tierra, Pilar, Paraguay. Given that information on P. labiomaculatus is not provided for specific specimens, we used pholidosis traits of this species for comparison of ranges but not for correlations. Morphological data were used to explore the variation in ventral and subcaudal scales among the Species in the group. Geographic baseline data (high resolution elevation maps) were taken from Consortium for Spatial Information (CGIAR-CSI), based on SRTM30 images (30 seconds resolution), available at www.diva-gis.org/ gdata (Jarvis et al. 2008). Ecoregion definition was based on Olson et al. (2001). GIS processing was performed in Quantum GIS 3.12.0. Results Phalotris shawnella sp. nov. http://zoobank.org/253E6610-D61C-49B7-B79F-0625C8FB72A5 Type locality. Rancho Laguna Blanca, Departamento San Pedro, Paraguay (Fig. 1). Holotype. CZPLT-H-594; adult male; collected during digging on 3 January 2014 (J-P. Brouard); Rancho Laguna Blanca, 23°48'43"S, 56°17'49"W (WGS 84), 204 masl, San Pedro department. Specimen complete but damaged during collection, being severed approximately at mid- body (Fig. 2). Diagnosis. Phalotris shawnella sp. nov. is assigned to the nasutus group on account of the pointed snout with prominent rostral shield and the fusion of the second and third temporal plates (Fig. 3A). The new species can be distinguished from all other members of the nasutus group by the combination of the following characters: 1) fifth supralabial in contact with parietal, 2) vertebral stripe present, 3) yellowish nuchal collar (2 or 3 dorsal scales long), 4) dull reddish color of head in adults, 5) broad, solidly or near solidly dark lateral bands, 6) red-orange ventral scales lightly and irregularly spotted with black, mainly on the posterior half of the body, and 7) a bilobed, extremely asymmetrical hemipenis, with enlarged, curved, lateral spines. Phalotris shawnella sp. nov. is differentiated from the individual members of the nasutus group and the only species known to occur sympatrically with it (P. multipunctatus) as follows. (The characteristics of Phalotris shawnella sp. nov. are given first, followed by the comparison species in parentheses): Phalotris nasutus Gomes, 1915: 1) broad black lateral bands running the length of the body (absent in P. nasutus or present vestigially on the posterior part of the body only); 2) supralabial concolorous with head (supralabials 72 paler than head); 3) ventral coloration red-orange with blackish smudges on the lateral part of the ventral scales, and scattered larger irregular black blotches (ventral immaculate pink); 4) ventral scales 185 in the male (ventrals in males < 182); 5) hemipenis bilobed and greatly asymmetrical (hemipenis only slightly asymmetrical). Phalotris lativittatus Ferrarezzi, 1993. Superficially closest to this species within the nasutus group, which shows little variation in appearance across the large range and specimen series available (H. Braz in litt.). It can be reliably distinguished from P. shawnella sp. nov. with the following characters: 1) Supralabials uniformly brownish red (supralabials pale in P. Jativittatus), 2) infralabials uniformly grey (infralabials with some dark markings); 3) scattered dark spots along the sides of the ventral scales (uniform pale ventral scales); 4) broad lateral band solid or nearly solid (lateral band with broad pale scale edges along entire length); 5) small spines at the lower part of the hemipenis (larger spines all along the body of the hemipenis). Phalotris nigrilatus Ferrarezzi, 1993. Geographically, this is the only species that approaches P. shawnella sp. nov. within the nasutus group and 1s the only species with which it shares two key characters: a solid dark lateral band and dark markings on the ventral scales. Phalotris nigrilatus is otherwise phenotypically strikingly different and the significant specimen series now available indicates that it is morphologically very conservative (Cacciali et al. 2020). 1) Presence of clear pale collar (absence of collar in P. nigrilatus), 2) Ventral dark markings irregular, diffuse and widely-spaced, mainly on the posterior half of the body (ventral dark markings dense and typically regular, at the edges of each ventral scale and along the entire underside); 3) Chinshields pale contrasting with dark infralabials (chinshields dark, not contrasting with infralabials); 4) Head brick red dorsally with brownish suffusions in adult (head black in adult); 5) thin spines on the hemipenis (thick spines). Phalotris concolor Ferrarezzi, 1993: 1) fifth supralabial in contact with parietal (separated in P. concolor), 2) presence of broad dark lateral band (lateral coloration uniformly red); 3) indistinct black vertebral line (dorsal coloration uniformly red); 4) ventral scales 185 in the male (212 ventral scales in the only male known). Phalotris labiomaculatus Lema, 2002. 1) Supralabials uniformly brownish-red, concolorous with _ rest of head (spotted black and white supralabials in P. labiomaculatus), 2) wide dark lateral band (body coloration uniformly orange with no dark lateral band); 3) yellow nuchal collar 2—3 scales wide (white nuchal collar 3-4 scales wide); 4) dark vertebral line present (no vertebral line); 5) irregular dark spots on the ventral scales (uniformly white ventral scales). Phalotris multipunctatus Puorto & Ferrarezzi, 1993. This is the only species of Phalotris known to occur sympatrically with P shawnella. 1) Scales of broad lateral bands lacking white spotted pattern (scales of broad lateral bands with white tips giving spotted pattern zse.pensoft.net 80 Smith, P. et al.: A new species of Phalotris from Paraguay Figure 2. Dorsal (left) and ventral (right) overviews of the holotype of P. shawnella sp. nov. The specimen was accidentally severed during collection. Scale bar: 2 cm. (Photograph by Jeremy Dickens). in P. multipunctatus), 2) red-orange ventral scales lightly and irregularly spotted with black, mainly on the posterior half of the body (ventral scales black with broad white posterior edges forming banded pattern); 3) head brick red (in adult) or black (in juvenile) lacking any white spotting (head black with profuse white spotting); 4) infralabials uniform (each infralabial with a single large white medial spot); 5) longitudinal dark mid-dorsal stripe present (longitudinal dark mid-dorsal stripe absent). Description of holotype. An adult male in two pieces, SVL 260 + 140 (=400) mm; TL 65 mm (16.25% of SVL); one preocular, two postoculars; temporals 0+1/0+1; loreal absent; supralabials 6(2—3)/6(2—3), fifth supralabial broadly contacts parietal; infralabials 7(1—5)/7(1—5), 1* to 4" contacting the anterior pair of chinshields and 4" to 5" contacting the posterior pair of chinshields; zse.pensoft.net posterior chinshields longer and thinner than anterior chinshields; dorsal scale rows 15-15-15; scales smooth lacking apical pits; 185 ventrals; anal plate divided; 35 paired subcaudals. Yellow nuchal collar two to three scales wide and posterior black collar one to two scales wide. Slight trace of incomplete anterior black collar, most evident laterally. Rostral prominent and wider than it is long (1.9 x 2.6 mm); nasal complete, twice as long as greatest width (2.2 x 1.1 mm), contacting the rostral anteriorly, the 1% and 2" supralabial ventrally, the preocular posteriorly, and the internasal and frontal dorsally; paired internasals slightly wider than they are long (1.4 x 2.2 mm); the second temporal longer than wide (3.1