Clelia clelia ( Daudin 1803 )

Scott Jr., Norman J., Giraudo, Alejandro R., Scrocchi, Gustavo, Aquino, Aida Luz, Cacciali, Pier & Motte, Martha, 2006, THE GENERA BOIRUNA AND CLELIA (SERPENTES: PSEUDOBOINI) IN PARAGUAY AND ARGENTINA, Papéis Avulsos de Zoologia (São Paulo) 46 (9), pp. 77-105 : 88-90

publication ID	https://doi.org/ 10.1590/S0031-10492006000900001
persistent identifier	https://treatment.plazi.org/id/03DDA01C-FFF4-CA11-4F0D-F9D3FCB8E424
treatment provided by	Felipe
scientific name	Clelia clelia ( Daudin 1803 )
status

Treatment

Clelia clelia ( Daudin 1803) View in CoL

Coluber clelia Daudin, 1803: Original description, type locality: Surinam View in CoL

Brachyrhytum occipitoluteum ; Boettger, 1885: Paraguay

Oxyrhopus Cloelia (part.); Serié, 1915: Department Central, Paraguay

Clelia clelia clelia ; Bailey, 1970: Argentina and Paraguay

Clelia clelia clelia (part.); Scrocchi & Viñas, 1990: Corrientes, Argentina and Department San Pedro, Paraguay

Clelia clelia clelia (part.); Cei, 1993: Northwestern and eastern Argentina

Clelia clelia View in CoL (part.); Aquino et al., 1996: 6 departments in Paraguay

Boiruna maculata View in CoL (part.); Giraudo & Scrocchi, 2002: Argentina

Boiruna maculata (part.); Giraudo, 2002: Northeastern Argentina

Boiruna maculata (part.); Arzamendia & Giraudo, 2002: Santa Fe, Argentina

Boiruna maculata (part.); Álvarez et al., 2002: Corrientes, Argentina

Clelia clelia ; Motte et al., 2004: Paraguay

Taxonomic History – Because of the low number of ventrals, Boettger’s (1885) Brachyrhytum occipitoluteum from Paraguay is probably the first record of C. clelia from the study area. Subsequently, from 1914 to 1979, a number of checklists recorded the species “clelia ” under the genera Oxyrhopus , Pseudoboa , and Clelia . However, all or most of those citations, here placed in Incertae Sedis, were composites of two or more species ( B. maculata , C. clelia , C. plumbea , and even C. rustica ), and they may not have included any true C. clelia . Bailey (1970) was probably the only author during this period that had a clear concept of the limits of C. clelia clelia . Starting in about 1985, the taxa C. occipitolutea (= Boiruna maculata ) and true C. clelia became confused under the name C. clelia (e.g., Scrocchi & Viñas, 1990).

Two papers were pivotal in determining the concept of C. clelia in Paraguay and Argentina. Scrocchi & Viñas (1990) codified the reigning confusion, explicitly combining all Argentine specimens of C. occipitolutea and C. clelia into one taxon: C. c. clelia . This taxonomy prevailed until Zaher (1996) showed that the correct name for C. occipitolutea was Boiruna maculata , and many Southern Cone specimens previously dubbed C. clelia pertained to that species. He saw no specimens of true C. clelia from localities south of Santa Cruz Province, Bolivia. This led subsequent authors to the conclusion that B. maculata was the only member of the two taxa ( Boiruna maculata , C. clelia ) in Argentina and Paraguay. All citations of Argentine B. maculata up to the present may include C. clelia .

Zaher (1996) further clarified the taxonomic puzzle by recognizing C. plumbea as a full species instead of a subspecies of C. clelia . This enabled Giraudo (2002) to separate specimens of C. plumbea from his Boiruna-C. clelia composite in northeastern Argentina. Although Giraudo (2002) recognized that specimens of C. clelia from northeastern Argentina fit descriptions of that species, he provisionally placed them in B. maculata because, according to Zaher (1996), C. clelia did not occur anywhere near Argentina.

Diagnosis – A low number of ventrals distinguishes most C. clelia from the two other large species ( B. maculata and C. plumbea ), although there is overlap in ventral scale counts of females of C. clelia (maximum 218) and B. maculata (minimum 214; Appendix 4, Fig. 4 View FIGURE 4 ). Like B. maculata , C. plumbea , and C. rustica , C. clelia usually has 7 supralabials on each side (Appendix 1). The loreal of C. clelia is usually larger than that of C. plumbea , contacting supralabials 2 and 3; in C. plumbea the loreal seldom contacts any but the second supralabial, or it may be indistinguishably fused with the postnasal or prefrontal (Appendix 3).

The adult ventral color pattern can differentiate C. clelia and B. maculata . In C. clelia , the dark dorsal coloration is present at least on the lateral tips of the ventral scales. In some specimens, the dark color extends towards the midventral line along the free edge of the ventral scale, but the center of the scale is usually free of dark pigment. Exceptionally the entire free border of posterior ventrals may be pigmented, but the entire ventral is never completely dark-colored as in B. maculata .

Giraudo (2002) discovered a color pattern detail that separates adult C. clelia and C. plumbea . Both species are dark gray or black dorsally, with largely ivory venters. However, in C. plumbea , the border between the dark dorsal color and the ivory venter forms a straight line on the lateral tips of the ventrals ( Fig. 1 View FIGURE 1 , photograph in Giraudo, 2002). In C. clelia , this border is dentate, with the dark color extending further on the free margin of the ventral than it does on the base of the scale ( Fig. 1 View FIGURE 1 ; photograph in Kempff Mercado, 1975).

Coloration in hatchling C. clelia and C. plumbea are similar. Both have uniformly red dorsal body scales, a black spot on the anterior dorsum, preceded by a white nape band and a black head cap ( Fig. 10 View FIGURE 10 ). Ventral surfaces are mostly white with some black pigment under the tail and on the chin. Hatchlings of B. maculata , C. bicolor and C. quimi may have red lateral scales, a white collar, and a dark head cap; but they also have a dark stripe the same color as the head cap down the center of the back.

Description – There are no descriptions of C. clelia from the Southern Cone that are not mixed with those of other large species, usually B. maculata or C. plumbea . Zaher’s (1996) description is uncontaminated by observations on other species, but it is sketchy and covers the species throughout its huge distribution. His southernmost specimens were from central Bolivia. Kempff Mercado (1975) has a photograph of a Bolivian specimen, and Figure 11 View FIGURE 11 is an Argentine specimen.

Clelia clelia vies with C. plumbea for being the largest member of the genus ( Fig. 3 View FIGURE 3 ). The total lengths of the smallest and largest of 19 C. clelia were 421 mm and 2200 mm. In our sample, there is no difference in size between the sexes (t-test; P>0.52).

Clelia clelia in Argentina and Paraguay has 193-218 ventrals, 62-88 subcaudals, and generally 7 supralabials (rarely 8 or 9; Appendix 1 and 4, Fig. 4 View FIGURE 4 ). The loreal scale is of a size normal for most colubrids, contacting the second and third supralabials (Appendix 3, Fig. 2A View FIGURE 2 ).

The hemipenis of C. clelia , illustrated and described by Zaher (1996), shows a large degree of variation. With one exception, our specimens have a relatively low number of extrasulcal spines (15-22; Appendix 2). A specimen from northeastern Paraguay ( MNHP 6695) that is geographically and ecologically isolated from the remainder of our sample has 37 extrasulcal spines ( Fig. 12 View FIGURE 12 ). The C. clelia hemipenis illustrated by Zaher (1996: Plate 4) from French Guiana is spineless except for a pair of extremely large extrasulcal spines. This hemipenis is so different from any that we observed that it may belong to a separate species; alternatively, it may belong to a hybrid or intergrade with C. plumbea , which has a spineless hemipenis.

The number of intrasulcal spines is also variable (Appendix 2). Most specimens have a single pair of spines, but MNHNP 3957 has only a single intrasulcal spine, and FML 11964 has none. The intrasulcal spines are unusually large in MNHNP 8489 from Paraguay.

Adult C. clelia are a uniform dark gray or black dorsally, with an essentially ivory-colored venter. Supralabials and infralabials are dusky, forming a transition between the dorsal and ventral colors. The lateral tips of the ventrals are dark like the dorsum. In some specimens, the dark color extends towards the midventral line along the free edge of the ventral scale. The center of the ventral scale is usually free of dark pigment. Exceptionally, the entire free border of posterior ventrals may be pigmented, but the entire ventral scale is never completely dark-colored. The underside of the tail often has a dark zigzag stripe where the pairs of subcaudals meet.

As in B. maculata , C. plumbea , and some Pseudoboa , occasional specimens of C. clelia can have large irregular blotches of white pigment.

Hatchling C. clelia have a bright red body dorsum and a white venter. A black cap covers the head, extending latero-ventrally as dusky coloration on the supralabials and mental. The cap may only reach the anterior tips of the parietals, or it may cover them. A white nape band follows the black cap, extending 3-4 scale rows posterior to the parietals. A black blotch 6-9 scale rows long and extending down the sides of the neck follows the white band. The underside of the tail may have a dark zigzag down the center and the tip may be black. A black-and-white photograph is in Dixon & Soini (1986).

As the juveniles grow, black pigment appears on the free tip of each dorsal scale. The pattern results in an overall darkening of the red body and white collar, but it never appears reticulate, as it may in juveniles of all of the other species except C. plumbea . The middorsal scales begin to darken first, but there is never a distinct middorsal stripe as in juvenile B. maculata , C. bicolor , and C. quimi . Further extension of the dark pigment results in the unicolor dorsum seen in adults. Faint indications of the white collar may persist in small adults.

Distribution – Clelia clelia has the widest distribution of any pseudoboine snake-indeed it has one of the largest ranges of any New World snake. From the northern limits in central México it extends south through Paraguay to central Argentina ( Bailey, 1970). It is widespread in tropical México, Central America, and South America north of the Amazon River, but Zaher (1996) had only four records south of the Amazon, in Perú and Bolivia. Our recognition that C. clelia occurs in Argentina and Paraguay extends the accepted distribution more than 900 km south of Santa Cruz, Bolivia to Santa Fe Province, Argentina.

Strussman & Sazima (1993) recorded the species from the Panatanal of western Brazil, and it may occur in the poorly sampled area where Bolivia, Brazil, and Paraguay come together. However, the Strussman & Sazima specimens may be B. maculata , which may also occur in the area.

In Paraguay and Argentina, C. clelia is found along the Río Paraguay in the upper Chaco, usually in areas subject to occasional flooding. The distribution extends eastward along large tributaries into moist forests in eastern Paraguay.