Bransonella sp.
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publication ID |
https://doi.org/ 10.4202/app.2008.0051 |
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persistent identifier |
https://treatment.plazi.org/id/03802969-223E-8048-AD5F-709BFD709DE4 |
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treatment provided by |
Felipe |
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scientific name |
Bransonella sp. |
| status |
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Bransonella sp. “A”
Fig. 18C View Fig .
Material.—Single tooth, UAPL 23511.
Description.—Base longer (am−pl) than wide (l−l; Table 2); lingual margin bifurcated ( Fig. 18C View Fig 1 View Fig , C 4 View Fig ); basal tubercle semicircular with nearly straight lingual margin ( Fig. 18C View Fig 4 View Fig ); apical button subdued with flat surface, in contact with intermediate cusp but slightly isolated from principal cusps, isolated from base lingual margin ( Fig. 18C View Fig 1 View Fig ); only two significant aboral foramina ( Fig. 18C View Fig 4 View Fig ), oral foramina absent. Principal cusps equally divergent; left cusp ( Fig. 18C View Fig 1 View Fig ) incomplete and worn, right cusp largely complete (but see Fig. 18C View Fig 1 View Fig ); both compressed with longest transverse axis 45° to labial margin ( Table 2); left cusp ( Fig. 18C View Fig 1 View Fig ) with about four labial cristae and possibly one on lingual side, right cusp with about six labial cristae and possibly one or two lingual cristae on proximal half. Intermediate cusp complete, straight, perhaps 3/4 length of principal cusps if complete, base practically fused to principal cusps; proximally compressed antero−posteriorly, distally slightly compressed labio−lingually or equidimensional (not conical); possibly two distal and three or four proximal cristae extending onto base on labial side,?four faint distal cristae on lingual side, proximally absent.
Remarks.—Tooth wear, probably from transport, precludes a full assessment of the cristae in UAPL 23511 ( Table 2). They appear finer than is typical for Bransonella ; on both principal cusps, they appear not to extend onto the base on the labial side, but this may be from wear. If the cristae did not extend onto the base, then the tooth would be unlike others assigned to Bransonella , although Johnson (1984: 183, fig. 8b) noted an exception. The base dimensions are reversed (am−pl> l−l, Table 2) from UAPL 23508–23510, but this is normal for most B. nebraskensis teeth ( Johnson 1984: fig. 2) and not unusual for B. lingulata ( Ivanov and Ginter 1996: fig. 2). The apical button is in contact with the intermediate cusp and isolated from the base lingual margin, as in B. nebraskensis ( Johnson 1984) ; it is nevertheless much smaller and more subdued than in this and other species. The small apical button, coupled with the low number of aboral foramina (compare Fig. 18C View Fig 4 View Fig with Johnson 1984: fig. 1), suggests UAPL 23511 is probably not B. nebraskensis , nor is it B. lingulata , which has a dominant apical button in contact with the lingual margin of the base. However, Alexander Ivanov (personal communication, December 2008) thinks it does belong to B. nebraskensis ; compare with Ivanov and Ginter (1996: fig. 1 N–R).
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