Atractus multicinctus ( Jan, 1865 )

Passos, Paulo, Mueses-Cisneros, Jonh Jairo, Lynch, John D. & Fernandes, Ronaldo, 2009, Pacific lowland snakes of the genus Atractus (Serpentes: Dipsadidae), with description of three new species, Zootaxa 2293, pp. 1-34 : 21-24

Atractus multicinctus ( Jan, 1865)

Figs. 13 , 14 , 15

Rabdosoma badium var. multicinctum Jan in Jan and Sordelli, 1865; Iconographie Générale des Ophidiens 10:plate 4, fig. 5.

Atractus badius— Boulenger, 1896; Catalogue of the Snakes in the British Museum 2:308 (part).

Atractus multicinctus— Boulenger, 1898; Proc. Zool. Soc. London 1898:116.

Atractus multicinctus— Boulenger, 1913; Proc. Zool. Soc. London 1913:1035.

Atractus multicinctus— Savage, 1960; Misc. Publ. Mus. Zool. Univ. Michigan 112:54.

Holotype: Specimen originally in the Museo Cívico di Historia Natural di Milano ( MCHNM), from ”Lima” without more precise data (see Jan and Sordelli, 1865). Specimen destroyed during World War II (S. Scali, pers. comm.). Savage (1960) considered as the locality to be Lima, capital of Peru (but see Remarks).

Diagnosis: Atractus multicinctus is distinguished from all congeners by the combination of the following characters: (1) 17/17/17 smooth dorsal scale rows; (2) two postoculars; (3) loreal long; (4) temporals 1+2; (5) seven supralabials, third and fourth contacting orbit; (6) six or seven infralabials, first three contacting chinshields; (7) five or six maxillary teeth; (8) four gular scale rows; (9) four preventrals; (10) 177–184 ventrals in females, 168–183 in males; (11) 31–36 subcaudals in females, 40–43 in males; (12) dorsal ground colour beige with wide black bands alternating on flanks and occasionally contacting opposite bands in the vertebral region; (13) venter uniformly creamish white; (14) moderate body size in female 312 mm SVL, and small in males 249 mm SVL; (15) tail moderate in females (12.6–13.5% SVL) and long in males (15.3–20.5% of SVL); (16) hemipenis strongly bilobed, semicapitate, semicalyculate.

Comparisons: Among all congeners, A. multicinctus shares only with A. clarki 17 dorsal scale rows, 31– 36 subcaudals in females and 34–43 in males, generally six infralabials, generally three infralabials contacting chinshields, five to seven large and well-spaced maxillary teeth, body diameter below 5 mm, banded colour pattern, wide cream occipital band constricted dorsally, venter predominantly creamish white. Atractus multicinctus differs form A. clarki by having 177–183 ventrals in males, dorsal ground colour beige or creamish white crossed by black bands of similar width or broader than light interspaces (vs. 153–165 ventral in males and dorsal ground colour black with narrow light bands smaller than black interspaces).

Description: Head twice as long as wide, slightly arched in lateral view, rounded in dorsal view; snout truncate in lateral view, slightly rounded in dorsal view; cervical constriction indistinct; rostral subtriangular in frontal view, broader than high, poorly visible in dorsal view; internasal longer than wide; internasal suture sinistral with respect to prefrontal suture; prefrontal as long as wide; supraocular sub-trapezoidal, twice as long as wide; frontal pentagonal, as long as wide; parietal about twice as long as wide; nasal divided; nostril between pre- and postnasal; prenasal twice as high as long; postnasal about as high as long, as high as prenasal; loreal long, contacting second and third supralabials; pupil round; postoculars equally high; upper postocular slightly longer than lower postocular; temporals 1+2; first temporal about three times as long as high; upper posterior temporals elongate, about three times as long as wide; seven supralabials, third and fourth contacting orbit; first two supralabials equally high, smaller than third and fourth supralabials; sixth higher and seventh longer than remaining supralabials; symphisial subtriangular, twice as broad as long; six infralabials, first three contacting chinshields; first pair in contact behind symphisial, preventing symphisial/ chinshields contact; chinshields three times longer than wide; four gular scale rows; four preventrals; 17/17/ 17 smooth dorsal scale rows; dorsals lacking apical pits, supra-anal tubercles, and keels; caudal spine moderate, conical, and rhomboid.

Maxillary arch: Arched in dorsal view, with four prediastemal and one or two postdiastemal teeth; first three teeth large, similar in size, moderately spaced, curved posteriorly, angular in cross section, robust at base, and narrower at apices; maxillary diastema moderately long; postdiastemal teeth significantly smaller than last prediastemal tooth; lateral process moderately developed, lacking posterior projection.

Colour in preservative: Dorsum of head with black cephalic cap extending from rostral to anterior region of parietals; occipital band cream covering mid-posterior parietal, temporal, and occipital regions; background of head black to dorsal margin of supralabials ventrally and to the level of the postocular posteriorly; supralabials uniform cream below to dorsal spots; mental region, preventrals, and venter immaculate cream; tail cream with small black dots concentrated on middle portion between median subcaudal sutures; dorsal ground colour of body beige or reddish light brown, with about 30 black bands (three scales long) alternating on the body flanks; bands reaching first or second scale rows ventrally and frequently connecting the opposite band in vertebral region; bands laterally rhomboid shaped and occasionally scattered with light pigment at the centre; around 30 beige interspaces smaller or of similar size to black bands (two or three scales long); interspaces covered with small diffuse black dots in the flanks and irregular black blotches at paraventral region (two scales long); irregular blotches frequently connected to black bands dorsally.

Hemipenis morphology (everted organ n = 1): Retracted organ bifurcates at fifth and extends to the level of eighth subcaudal. Hemipenis strongly bilobed, semicapitate, semycaliculate; lobes clearly distinct from capitulum and of equivalent size to hemipenial body; lobes centrifugally oriented, subcylindrical with flattened apices; left lobe longer than right; lobes and capitulum covered with small and concentrated spinulate calyces; spinules gradually relaced with papillae toward apices of lobes; capitular groove indistinct on the sulcate and barely evident on the asulcate side of hemipenis; capitulum situated just above sulcus spermaticus bifurcation, and smaller than hemipenial body on the sulcate side; capitulum limited by moderately sized hooked spines arranged in diagonal series on the sulcate side of organ; capitulum retracted medially on the asulcate side, and slightly longer than hemipenial body; intrasulcar region of capitulum with three narrow and large hooked spines among calyces; sulcus spermaticus bifurcates at basal portion of hemipenial body; sulcus spermaticus branches running parallel to mid- sulcus extension before diverging at the base of lobes; branches of sulcus spermaticus with centrifugal orientation, reaching tip of lobes; sulcus spermaticus margins moderately expanded, bordered with spinules before sulcus spermaticus bifurcation and later with papillae; hemipenial body subelliptical, slightly broader than capitulum, uniformly covered with moderately hooked spines; spines concentrated on lateral portion of sulcate side and region adjacent to capitulum on the asulcate side; basal naked pocket restricted to proximal region of hemipenial body; basal portion of hemipenis with longitudinal plicae and disperse spinules ( Fig. 4 b).

Variation: Largest male 249 mm SVL, 51 mm CL; largest female 312 mm SVL, 42 mm CL; tail 15.3– 20.5% (x¯ = 18.3; SD = 2.7; n = 3) SVL in males, 12.6–13.5% (n = 2) SVL in females; 168–183 (x¯ = 177; SD = 7.9; n = 3) ventrals in males, 177–184 (n = 2) in females; 40–43 (x¯ = 41; SD = 1.7; n = 3) subcaudals in males, 31–36 (n = 2) in females; 9–10 (n = 2) dorsal scale rows at the level of second subcaudal; 3.1–4.6 mm (n = 2) diameter of body; 5 (n = 2 sides) or 6 (n = 4 sides) maxillary teeth.

Distribution: Pacific coast of Colombia and Ecuador from Buenaventura (03º54’N, 77º04’W) in the department of Valle del Cauca of Colombia to Paramba (0º49’S, 78º21’W) in the province of Los Rios of Ecuador. Atractus multicinctus inhabits rainforest at elevations of 0–770 m ( Fig. 2 ).

Remarks: Jan in Jan and Sordelli (1865) described Rabdosoma badium var. multicinctus on the basis of a specimen from Lima without specify country provenance. Boulenger (1896) synonymized Atractus badium multicinctus with the nominal species ( A. badius ). Subsequently, Boulenger (1898) resurrected A. multicinctus based on a specimen from Paramba, province of Imbabura, Ecuador, establishing that ventral count differences guarantee both species’ distinction. Boulenger (1913) reported an individual of A. multicinctus from Peña Lisa, Condoto in the department of Chocó, Colombia. Savage (1960) agreed with Boulenger’s associations and reported five additional specimens of A. multicinctus from the Pacific versant of Ecuador. Our study of the original plate from R. b. multicinctum, the examination of Boulenger’s sample, and analysis of additional specimens from Buenaventura corroborates identifications by Boulenger (1898, 1913) and Savage (1960).

Savage (1960) interpreted the type locality of A. multicinctus as the capital of Peru and suggested this provenance was in error because Atractus records are lacking for the Pacific coast of Peru. However, Jan and Sodelli (1865) did not provide any information about the country origin of the holotype of A. multicinctus . In our view, there is no compelling evidence in the original publication to recognize the type locality of A. multicinctus as Lima capital of Peru. In the course of this study we found a locality called Lima in the Pacific lowlands of Ecuador in the province of Los Rios, 200 km south of Paramba (the southernmost record of the species, see Savage 1960), which could be considered as the type locality. However, the locality of Lima in Los Rios (also called Playa Lima) is a small hamlet that has its origins in the old Playa Lima farm, and was formed about 50 to 80 years ago. Even the Playa Lima farm is not as old as the specimen described by Jan (D. Cisneros-Heredia, pers. comm.). Therefore, although we agree with Savage (1960) that the holotype of A. multicinctus is not from Peru, the available evidence precludes a type locality restriction to Lima in the province of Los Rios, Ecuador.

Figures

FIGURE 2. Geographic distribution of the Atractus multicinctus species group.

FIGURE 4. Sulcate and asulcate sides of the hemipenis of (A) Atractus clarki (ICN 10826) and (B) Atractus multicinctus (ICN 7075). Scale = 5 mm.

FIGURE 13. General view of original Sordelli’s plate of the Atractus multicinctus. Modified from Jan & Sordelli (1865).

FIGURE 14. Dorsal (A) and ventral (B) views of Atractus multicinctus (ICN 7075). SVL 228 mm, CL 35 mm.

FIGURE 15. Dorsal (A) and ventral views (B) of head and lateral view of body (C) of Atractus multicinctus (ICN 7075). Scale = 5 mm.