Belongs within: Pentamerida.
The Virgianidae are a family of pentameridan brachiopods known from the Upper Ordovician and Lower Silurian (Amsden & Biernat 1965).
Characters (Amsden & Biernat 1965): Smooth to costate, with interareas absent or poorly developed. Spondylium moderate in size to small, supporting septum short or absent; spondylium and septum relatively thick-walled. Brachial apparatus much abbreviated; outer plates abbreviated or absent, inner plates small; muscle area located in front of brachial apparatus.
<==VirgianidaeRZJ04
| i. s.: Plicidium Rong & Yang 1981RZJ04
| Pleurodium Wang 1955RZJ04
| `--*P. tenuiplicatum (Grabau 1925) [=Conchidium tenuiplicatus]AB65
|--Holorhynchus Kiaer 1902B75, RZJ04 [incl. Nondia Boucot & Chiang 1974RZJ04]
| |--*H. giganteus Kiaer 1902 [incl. H. giganteus latisulcifer Rukavishnikova & Sapelnikov 1973]RZJ04
| |--‘Nondia’ canadensis Boucot & Chiang 1974RZJ04
| |--H. cinghizicus Borissiak 1955RZJ04
| |--H. lalaensis Sapelnikov 1963RZJ04
| |--H. sinicus Fu 1982RZJ04
| `--H. tuberosus Sapelnikov 1963RZJ04
`--+--Virgianella Nikiforova & Sapelnikov 1971B75, RZJ04
| |--V. glabella (Rong & Yang 1981)RZJ04
| `--V. sogdianica Nikiforova & Sapelnikov 1973 [=Holorhynchus (Nondia) sogdianica]RZJ04
`--+--Virgiana Twenhofel 1914B75, RZJ04
| `--*V. barrandei (Billings 1857) [=Pentamerus barrandi]AB65
`--Platymerella Foerste 1909B75, AB65
`--*P. manniensis Foerste 1909AB65
*Type species of generic name indicated
References
[AB65] Amsden, T. W., & G. Biernat. 1965. Pentamerida. In: Moore, R. C. (ed.) Treatise on Invertebrate Paleontology pt H. Brachiopoda vol. 2 pp. H523–H552. The Geological Society of America, Inc.: Boulder (Colorado), and The University of Kansas Press: Lawrence (Kansas).
[B75] Boucot, A. J. 1975. Evolution and Extinction Rate Controls. Elsevier Scientific Publishing Company.
[RZJ04] Rong, J.-Y., R.-B. Zhan & J. Jin. 2004. The Late Odovician and Early Silurian pentameride brachiopod Holorhynchus Kiaer, 1902 from north China. Journal of Paleontology 78 (2): 287–299.