DIDELPHIMORPHIA

MacPhee, Ross D. E., Gaillard, Charlène, Forasiepi, Analía M. & Sulser, R. Benjamin, 2023, Transverse Canal Foramen And Pericarotid Venous Network In Metatheria And Other Mammals, Bulletin of the American Museum of Natural History 2023 (462), pp. 1-125 : 26

DIDELPHIMORPHIA

DIDELPHIS ( DIDELPHIDAE ) (figs. 2–5). Compared with other marsupials, the cephalic vasculature of the Virginia opossum ( D. virginiana ) may be considered relatively well explored, but most investigations cover major vessels only and provide little information on PCVN components (see literature summaries by Aplin, 1990). Shindo’s (1915) comparative investigation of the cavernous sinus in mammals may be considered a landmark because it includes the first detailed study of cephalic venation in marsupials (young specimens of D. virginiana and Acrobates sp. ). The ICV is described, but not named, as arising from the caudal aspect of the CS and passing through the carotid foramen to join the “vein of the roof of the nasopharynx” ( Shindo, 1915: 398 [trans.]). The identity of this last vessel is not apparent from Shindo’s text; it may represent one of the pharyngeal components of the PVP or even the TCV (also not recognizably identified). The BVP is not distinguished as such, although a “ v. thyreoidea ” has the expected relations for this vessel as it runs lateral to the larynx and thyroid gland to discharge into the IJV ( Shindo, 1915: 395). The VPS (= sinus petrobasilis) is described as leaving the chondrocranium through the jugular foramen to unite with the IJV, although these vessels have separate exit foramina in adult Didelphis (fig. 2B). Connections of these vessels with the condylar veins, lateral head vein, and internal vertebral venous plexus are also briefly mentioned or illustrated.

Toeplitz (1920) described some aspects of cephalic venation in the closely related species D. marsupialis , but most of her relevant text concerns carotid canal homology, not content, in different vertebrates (see MacPhee and Forasiepi, 2022). She illustrated the ICV (= “Sin. intercavern. post.”) as separating from the CS within the