Published online by Cambridge University Press: 14 July 2015
The genera Lissopleura, Sphaerirhynchia, Pectorhyncha, Yanishewskiella, and Terebratuloidea have been investigated to elucidate their internal features and taxonomic relationships. Specimens of the type species of these genera were sectioned. Lissopleura remains slightly enigmatic in that the holotype of Lissopleura aequivalvis is thinner and has a less pronounced fold than most specimens in the collection, including the one sectioned by us. The holotype is probably immature and is within the range of variation of specimens from the type area. The internal features lead us to assign Lissopleura to the Trigonirhynchiidae. Sphaerirhynchia wilsoni has a short septalium without a cover plate and other features that place it in the Hebetoechiidae. Pectorhyncha obtusiplicata has a very thick shell and a septalium filled by a large, bilobed cardinal process. The genus has several features similar to Obturamentella, and is assigned to the Obturamentellidae. Yanishewskiella angulata, which is retained within the Tetracameridae, has a spondylium with lateral buttresses, and a septalium into which the medium septum projects. Terebratuloidea davidsoni has small dental plates, and is assigned to the Allorhynchidae.
To send this article to your Kindle, first ensure no-reply@cambridge.org is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about sending to your Kindle. Find out more about saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Find out more about the Kindle Personal Document Service.
To save this article to your Dropbox account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you used this feature, you will be asked to authorise Cambridge Core to connect with your Dropbox account. Find out more about saving content to Dropbox.
To save this article to your Google Drive account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you used this feature, you will be asked to authorise Cambridge Core to connect with your Google Drive account. Find out more about saving content to Google Drive.