Leptophis bolivianus Oliver, 1942

Albuquerque, Nelson Rufino De & Fernandes, Daniel S., 2022, Taxonomic revision of the parrot snake Leptophis ahaetulla (Serpentes, Colubridae), Zootaxa 5153 (1), pp. 1-69 : 19-20

Leptophis bolivianus Oliver, 1942

( Figs. 9 , 10 , 11A–B )

Leptophis ahaetulla — Griffin 1916: 184 (in part) (Griffin listed four specimens deposited in Carnegie Museum as L. ahaetulla ,

and the CM 23 (examined) was subsequently designated as one of the paratypes of L. a. bolivianus by Oliver (1942: 2) ;

Wallach, Williams & Boundy 2014: 372 (in part). Leptophis ahaetulla bolivianus Oliver, 1942: 1 . Male holotype (UMMZ 67973; examined). Type locality: Buenavista (18°36′0S,

59°19′60W, 252 m asl), Department of Santa Cruz, Bolivia; Peters & Orejas-Miranda 1970: 63; Tipton 2005: 161. Thalerophis richardi bolivianus — Oliver 1948: 225. Leptophis ahaetulla [ bolivianus ]— International Commission of Zoological Nomenclature 1958: 270. Leptophis bolivianus — Torres-Carvajal & Téran, 2021: 6.

Diagnosis. Leptophis bolivianus can be distinguished from its congeners by the following unique combination of character states: (1) head scales distinctly edged with black and usually with two or more poorly defined, diffuse black spots on each parietal; a distinct, elongated black spot (occasionally two small spots) on each supraocular; preocular stripe absent; (2) adult color pattern with no dark dorsal bands; (3) dorsum greenish blue, with scales slightly edged with black; (4) dorsal scales keeled, except for the first dorsal row on each side; keels of dorsals slightly black; (5) loreal scale absent; (6) ventrals 152–167 in males, 156–173 in females; (7) subcaudals 135–157 in males, 131–154 in females; (8) keels on dorsal scales of tail short, but distinct, occasionally along the entire tail length; (9) maxillary teeth 20–24; (10) TL/ SVL: 95% CI = 0.595 –0.626 (n = 17); (11) small spines at first basal row of hemipenial body; (12) asulcate side of hemipenis similar to sulcate side .

Comparisons. Leptophis bolivianus differs from all members of the L. ahaetulla complex by the combination of head scales distinctly edged with black and usually with two or more poorly defined, diffuse black spots on each parietal; a distinct, elongated black spot (occasionally two small spots) on each supraocular ( Fig. 10A–D ) (vs. head scales not edged with black, with or with no black spot on each parietal; a small black spot on each supraocular). It differs from parapatric L. nigromarginatus by having ventrals not edged with dark greenish blue or blue ( Fig. 10G ) and distinct keels on the dorsal scales of tail (vs. ventrals edged with dark greenish blue or blue, Fig. 23B , and no keels on dorsals of the tail), by higher number of ventrals for males 95% CI = 156.2–161 and females 95% CI 162.4–166 (vs. 151.6–153 and 155.9–157, respectively). Leptophis bolivianus is further distinguished from L. nigromarginatus by TL/SVL 95% CI = 0.595 –0.626 (vs. 0.640 –0.649) ( Table 2).

Variation and sexual dimorphism. Largest male SVL 710 mm, TL 433+ mm and largest female SVL 700 mm, TL 418+ mm; ventrals 152–167 in males (158.7 ± 4.6, n = 16), 156–173 in females (164.4 ± 4.6, n = 21); subcaudals 135–157 in males (143 ± 7.4, n = 8), 131–154 in females (144 ± 7.8, n = 9); supralabials 7–9 (8.0 ± 0.2, n = 74), with fourth–fifth (94.5%, n = 70), or, rarely, fifth–sixth (5.5%, n = 4) bordering orbit; infralabials 9–12 (10.0 ± 0.5, n = 72), with first 5 (79.7%, n = 59), first 6 (17.6%, n = 13), or, rarely, first 4 (2.7%, n = 2) contacting first chin shields; preocular 1 (n = 36) and a single specimen with 2 on right side; postoculars 2 (n = 36) and a single specimen with 3 on right side; anterior temporal 1 (n = 37); posterior temporal 1–2 (1.7 ± 0.4, n = 74); keels more developed in adult males than adult females.

Paratype FMNH 35614 possess two small black spots on each supraocular scale, paratype FMNH 35620 possess two small black spots on left supraocular, holotype UMMZ 67973 possess one elongated black spot on each supraocular, and paratype UMMZ 67976 b possess two small black spots on left supraocular and one elongated black spot on right supraocular; parietal scales possess a poorly defined, diffuse black spot on each specimen though they are more elongated in the holotype UMMZ 67973 ( Fig. 10C ) . AMNH 141443 ( Fig. 10E ) , a female of 367 mm in total length, and UMMZ 67977 , a male of 521 in total length (but tail incomplete), are ornamented with bands in anterior and middle region of body, similar to those found in juveniles of other species of Leptophis (see Oliver 1948; this study). Females have more ventrals than males (F 1,37 = 14.0674; P <0.01), but no significant difference in subcaudal counts was observed (F 1,17 = 0.0735; P = 0.7856). Dorsal scales of tail can be keeled from the point of reduction from six to four rows (a female that also bears the USNM number 67977) ( Fig. 10F ) to the point of hundredth tenth subcaudal scales, corresponding to 36.4% TL ( UMMZ 67974 ). On the other hand, all scales of upper surface of tail are keeled in AMNH 22446 and AMNH 104563 . The TL/SVL showed no significant difference between females and males (F 1,15 = 2.3807; P = 0.1407).

Hemipenial morphology. Single retracted organ examined extends up to seven-eight subcaudals. Everted hemipenis unilobed, noncapitate; sulcus spermaticus centrolineal, undivided, extending from base to tip of lobe; basal portion bears small spines distributed in 6 rows approximatelly encircling the organ; first row bears 7 hooked spines slightly larger than those in other rows; spinules widely scattered adjacent to sulcus spermaticus; small calyces ornamented with 10–12 fringing papillae concentrated above most distal row of basal spines whereas large-sized calyces have 5–8 fleshy papillae concentrated along distal portion of hemipenial body; papillae gradually decrease in length toward distal portion of hemipenis; distal portion of lobe completely calyculate; asulcate side similar to sulcate side ( Fig. 11A–B ).

Coloration in life. Dorsum of the head Light Emerald Green (142), distinctly edged with black; usually two or more poorly defined, diffuse black spots on each parietal and distinct, 1–2 black spots (occasionally elongate) on each supraocular scale; rows II–IV (occasionally V) in anterior portion of the body (before body scale reduction from 15 to 11) Pale Greenish Yellow (86); rows IV–VII (occasionally V–VII) in anterior portion of the body Light Emerald Green (142); dorsal scales slightly edged with black; keels of dorsal scales slightly black; narrow Jet Black (300) postocular stripe covering upper edge of lower postocular, lower edge of upper postocular, lower margin to one-third of anterior temporal, half of lower posterior temporal and upper edges of last two supralabials; postocular stripe may extend beyond seven scales onto nuchal region; first five to seven supralabials, as well as infralabials, chin, throat, and venter white; last two supralabials below black upper edges of postocular stripe white.

Distribution and natural history. Known only from the departments of Beni and Santa Cruz in Bolivia. These snakes were collected up to 500 m asl in the tropical and subtropical dry broadleaf forests ecoregion, as defined by Olson et al. (2001) ( Fig. 18 ).

Remarks. As noted by Oliver (1948: 226) one of the most remarkable variations in the head color pattern of Leptophis bolivianus consists of differences of the distribution and extent of spots on the dorsal surface of the head ( Fig. 10A–D ). Oliver (1948: 226) indicated intergradation between L. a. bolivianus and L. a. nigromarginatus through a male specimen (AMNH 22446) from Rurrenabaque, Beni, Bolivia since it has an intermediate color pattern and a number of ventrals similar to L. a. nigromarginatus . The accumulation of new specimens since Oliver’s (1948) revision, however, reveals that the number of ventrals (153) of AMNH 22446 falls within the variation range for males of L. bolivianus ( Table 2).

Figures

FIGURE 9. Color patterns and color tones variability of Leptophis bolivianus: MNKR 4332 (SVL 920 mm), a female from Estancia Caparu, Provincia Chiquitos, Santa Cruz, Bolivia. Note the (A) general color pattern and the (B) postocular extending beyond seven scales onto the nuchal region (indicated by the arrow) in this specimen, respectively. Photos by L. Gonzales.

FIGURE 10. Color patterns and color tones variability of Leptophis bolivianus: (A) Paratype FMNH 35614, SVL 727 mm, (B) Paratype FMNH 35620, SVL 1118 mm, (C) Holotype UMMZ 67973, SVL 1079 mm and (D) Paratype UMMZ 67976b, SVL 755 mm—all with incomplete tail—showing the variation in the distribution, number and extent of black spots on the supraocular and parietal scales (see text for discussion); (E) AMNH 141443, SVL 367 mm, a female from San Antonio de Parapeti, Santa Cruz, Bolivia exhibiting the banded pattern typical of juveniles of most species of Leptophis, scale bar = 0.5 cm; (F) Female paratopotype that also bears the USNM number 67977, note that the dorsal scales of its tail are keeled only from the point of reduction from six to four rows (indicated by the arrow), scale bar = 1 cm; (G) Holotype UMMZ 67973, SVL 1079 mm showing the ventral scales not edged. Courtesy of The Field Museum, FMNH 35614 and FMNH 35620 (C), D. Kizirian (E) and N.R. Albuquerque (F–G).

FIGURE 11. Sulcate (left) and asulcate (right) sides of the hemipenes of Leptophis bolivianus (AMNH 104564) from Estancia Yutiole, department of Beni, Bolivia (A–B); L. coeruleodorsus (TCWC 46262) from municipality of San Fernando de Apure, state of Apure, Venezuela (C–D); L. liocercus (CZGB 1149) from municipality of Ilhéus, state of Bahia, Brazil (E–F). Note that although the hemipenis of CZGB 1149 is slightly bilobed, its sulcus spermaticus remains unbifurcated until the apical portion of the organ; L. nigromarginatus (LPHA 1731) from municipality of Santarém, state of Pará, (G–H); and (TCWC 42177) from Centro Union, departament of Loreto, Peru (I–J). Although the first row of basal spines is small in the four species, the two spines adjacent to sulcus spermaticus are larger than those in other rows. Scale bars = 0.5 cm. Photos by D. Kizirian (A–B) and N.R. Albuquerque (C–J).

FIGURE 18. Distribution of Leptophis bolivianus, L. liocercus, L. marginatus, and L. nigromarginatus based upon the material examined.

FIGURE 23. Color patterns and color tones variability of Leptophis nigromarginatus: (A) dorsal view of the head and (B) ventral view of the body of the holotype (BMNH 1946.1.5.7) from “Upper Amazons”. Arrow indicating ventral scale edged anteriorly and laterally with greenish blue, a characteristic thought by Oliver (1948: 246) to be typical of L. a. ortoni. Note two black spots in center of each parietal scale, a larger black spot on right supraocular scale, and two smaller spots on left supraocular scale; (C) KU 112279 and (D) KU 155512, a female and a male, respectively, from Santa Cecília, Ecuador. Both show distinct differences in the prominence of supracephalic black borders and spots, being both more prominent in the female specimen. Scale bar = 0.5 cm. Photos by N.R. Albuquerque (A –B) and A. Motta (C–D).