This specimen, a male having 144 ventrals and 55 caudals, was found beneath bark on a log in the forest. There is a black band five scales in length on the nape followed posteriorly by a red band six scales in length and then by a complete black band one and one-half scales in length. The rest of the body is dull red with 16 incomplete black bands one to one and one-half scales in length on the anterior two-thirds of the body.
Oxybelis aeneus aeneus (Wagler)
Chinajá, 1; 20 km. NNW of Chinajá, 1.
One individual was found in a low tree; the other was in a bush. Both specimens are males; the largest has a body length of 754 mm. and a total length of 1286 mm. Bogert and Oliver (1945:388) distinguished O. aeneus aeneus in Central and South America from O. aeneus auratus in México in that the diameter of the eye is more than the length of the internasal, whereas in O. aeneus auratus the diameter of the eye is less than the length of the internasal. Stuart (1958:27) stated that on the basis of this character three specimens from Tikal in northeastern El Petén definitely were O. aeneus aeneus. Of the present specimens from southern El Petén, one has an internasal:eye ratio of 1.08; the other has a ratio of 0.87. A careful review of these snakes is needed to verify the validity of the characters used to separate the subspecies and to determine areas of intergradation. The local name for the vine-snake is bejuquillo.
Pliocercus euryzonus aequalis Salvin
Chinajá, 1; Río San Román, 1.
These specimens are tentatively referred to P. euryzonus. KU 57160 is a female having 130 ventrals, 87 caudals, and 23 black rings on the body; KU 58150 is a juvenile having 128 ventrals, 79 caudals, and 27 black rings on the body. In both specimens the tip of the snout is yellow; a broad yellow band on the parietals and temporals is bordered posteriorly by a black band on the nape. The black rings on the body are not bordered by yellow, but black rings on the tail have yellow borders ventrally. In the red interspaces between the black rings, black flecks and spots, especially posteriorly, tend to form secondary black rings (Fig. 6a). According to Stuart (1948:71), P. euryzonus aequalis has 25 to 27 black rings on the body, whereas P. elapoides salvini, which also occurs in El Petén, has 15 to 23 black rings.
Fig. 6. Dorsal color patterns of Pliocercus euryzonus aequalis (A) and Micrurus affinis apiatus (B).
The specimen from the Río San Román contained a partly digested Bolitoglossa moreleti mulleri. Locally Piocercus is called coral or coralillo.