Thursday, January 20, 2011

"Damalosaurus" - Zhao's nomina nuda part 6

 Following along our survey of Zhao's sauropods, note he originally spelled this one with an 'o', unlike most subsequent authors.

"Damalosaurus" Zhao, 1983
"Damalasaurus laticostalis" Zhao, 1985
"Damalasaurus magnus" Zhao, 1985
= "Damalosaurus laticostalis" [sic] Chure and McIntosh, 1989
= "Damalosaurus magnus" [sic] Chure and McIntosh, 1989
= "Damalasaurus magnas" [sic] Zhang and Li, 1997
Etymology- Named for Damala Mountain in Qamdo, with the species referring to wide ribs (laticostalis) or large size (magnus).
Early Jurassic
Middle Daye Group, Daye, Qamdo County, Tibet, China
Material- (~15 m) specimen including dorsal rib
Comments- The species is listed as "magnus" in the text, but "laticostalis" in the plate caption.  Olshevsky (1991) listed "laticostalis as the type, though I consider it probable only one species is intended by Zhao since two are never present in faunal lists together (Zhao and Cheng, 1985; Zhang and Li, 1997; Fang et al., 2006).  Fang et al. use "laticostalis" for the species, suggesting it is the intended one since Zhao is a coauthor.  Zhao (1985) includes a photograph of a dorsal rib in situ, which the length estimate above is taken from assuming proportions like Barapasaurus.   Glut (1997) incorrectly stated it is Middle Jurassic in age.  Weishampel et al. (2004) list this as an undescribed sauropod in their faunal list. 

Dorsal rib of "Damalosaurus laticostalis/magnus" in matrix, from Zhao (1985).

Relationships- Stated by Zhao (1983, 1985) to be a primitive sauropod.  Chure and McIntosh (1989) listed it as a cetiosaurid, while Lambert (1990) and Olshevsky (1991) listed it as a brachiosaurid.  Glut (1997) only listed it as Sauropoda incertae sedis.  Fang et al. (2006) place it in Cetiosauridae, noting again it's a primitive sauropod. As those authors placing it in Brachiosauridae have never seen the specimen, and brachiosaurids are currently unknown from Asia or the Early Jurassic, that assignment seems less likely.  Since Cetiosauridae is currently viewed as a grade of basal eusauropods, "Damalosaurus" is here placed as Sauropoda incertae sedis.

1 comment:

  1. The first step to take gender out of the shadows is to consider and present them with as much information as possible.

    The trouble is that with the passage of time these remains may be lost and never be properly described, examples are many, but I want to emphasize the Brachiosaurus nougaredi. Only a few photographs and a series of measurements of a sacrum that may not be the same issue that the tibia is lost forever.

    And never was an image that will help clarify the details of these bones.

    The same can happen the same with Bruhathkayosaurus, whose description and illustration left more questions than answers. Incidentally, the alleged tibia 2 meters seems much more a fibula by its thinness and shape when compared with other titanosaurs.