Bavarioboa hermi

Description. Trunk vertebrae: All but one trunk vertebrae come from the middle trunk portion of the column. Some of them are preserved in relatively good condition, perhaps due to their robust morphology as characteristic of constrictors. In lateral view, these vertebrae are as high as long. In dorsal and ventral views, they are distinctly wider than long. In the largest and best-preserved vertebra HLMD-Ez 2148, the centrum length measures 5.7 mm, centrum width - 7.2 mm, centrum length / centrum width equals 0.8. The interzygapophyseal constriction, especially in larger vertebrae, is weakly expressed. The centrum is subtriangular in shape. The haemal keel is prominent, broad and slightly broadening posteriorly. In a few vertebrae, however, the keel looks like a biconcave lens owing to the presence of a distinct constriction, located at the level of the subcentral foramina, and prominent broadenings at the anterior and posterior ends. The subcentral grooves and subcentral ridges are prominent. The neural arch is moderately depressed. The neural spine is very low (approximately three times longer than high), thick, and widening posteriorly (Fig. 18 A). It occupies more than one half the length of the neural arch and begins immediately behind the zygosphenal articular facets. The zygosphenal roof is slightly convex or roughly straight in dorsal view. The prezygapophyseal and postzygapophyseal articular facets are usually subsquare in shape. The prezygapophyseal processes (if preserved) are very short and hardly visible dorsally. The paradiapophyses are subsquare in outline, higher than long, with indistinct subdivision into para- and diapophyseal portions. The cotyle and condyle are slightly flattened. The subcentral and lateral foramina are large. The paracotylar foramina are absent (Fig. 18 D). In the sole anterior trunk vertebra HLMD-Ez 2146, the haemal keel is replaced by a ventrally directed hypapophysis (its distal portion is broken). The neural spine of this vertebra is very short and relatively high in lateral view. Apart from these characteristics, the anterior trunk vertebra does not differ significantly from the middle trunk vertebrae. Cloacal vertebra: One cloacal vertebra HLMD-Ez 2149, as characteristic for the sacral portion of the column, is provided with paired lymphapophyses (their distal ends are broken). The centrum length measures 3.4 mm, centrum width - 4.1 mm, centrum length / centrum width equals 0.8. Surprisingly, located on the ventral side of the centrum, minute but distinct paired haemapophyses are present, thus far the trait unknown in the genus Bavarioboa (see below). Caudal vertebrae: Four caudal vertebrae are provided with paired pleurapophyses (missing or partly missing in some vertebrae). In the largest caudal vertebra HLMD-Ez 2150, the centrum length is 4.0 mm, centrum width 4.5 mm, centrum length / centrum width 0.9. Situated on the ventral side of the centrum, are short but distinct paired haemapophyses (partly broken).

Fig. 18 A-E

Material. Forty-two trunk vertebrae HLMD-Ez 2146 - 2148, one cloacal vertebra HLMD-Ez 2149, four caudal vertebrae HLMD-Ez 2150 and HLMD-Ez 2150 a.