Šnadjr (1980, p. 76) erected the proetid trilobite subgenus Coniproteus (Ryckholtia), with the type species Proetus ryckholti Barrande, 1846, from the Silurian (Ludlow, Kopanina Formation) of the Prague Basin, Czech Republic, perhaps better known to geologists as the Barrandian type area in Bohemia. Although originally designated as a subgenus (e.g., Chlupáč et al., 1980, p. 175; Chlupáč and Kukal, 1988, p. 114; Kříž et al., 1993, p. 819), Ryckholtia Šnadjr was subsequently elevated to generic rank (e.g., Sepkoski, 2002, p. 189, 519; Jell and Adrain, 2003, p. 441, 477; Edgecombe and Wright, 2004, p. 183).

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.

New Devonian fossil material from Bolivia includes internal molds of two species of paleotaxodont bivalve, Palaeoneilo musculosa (Knod) and P. pondeana (Hartt and Rathbun), with numerous accessory muscle scars. The unusual pattern of these scars appears to have been derived from excessive splitting. These muscle scars are described and a tentative interpretation is made. An adaptative role cannot be determined with certainty and it appears that these patterns were short-lived novelties without later success.

Amphissites insignis Croneis and Thurman, 1939, is a readily identifiable ostracode species because of the unique configuration of carinae and ridges on the surface of the valves. The species had adapted to both shale and limestone environments of deposition, has a wide geographic distribution in the United States (Alabama, Arkansas, Illinois, Montana, Nevada, Tennessee, and Texas), and is confined to the uppermost part of the Chesterian Series (foraminiferal zones 18 and 19). The description of this species is amended and specimens are illustrated for the first time from Nevada, Montana, Arkansas, and Tennessee, indicating that the species is a biostratigraphic indicator of the uppermost part of the Chesterian sedimentary sequence. Ontogenetic development of A. insignis is reconstructed. A. sp. 1 (Late Mississippian) and A. sp. 2 (Early Pennsylvanian) are illustrated in open nomenclature.

Specimens of macroalgae are reported and described herein from newly discovered algal-Lagerstätten within the Llandoverian Earlton Formation at two localities separated by a distance of 45 km in the Timiskaming outlier of Ontario, Canada. Both localities are characterized by abundant specimens of the Codium-like bryopsidalean green alga Thalassocystis striata, the details of which, including within-assemblage morphological variation, compare closely to material from the type locality. Previously, this noncalcified taxon was known only from the Llandoverian Schoolcraft Formation in northern Michigan, ~500 km to the west. These new occurrences provide additional evidence that the alga-bearing intervals within the Earlton Formation at both Timiskaming localities correlate with the Schoolcraft Formation in the Michigan Basin. An associated noncalcified form at one of the Timiskaming localities is described as a new genus and species, Earltonella fredricksi LoDuca, n. gen. n. sp., the thallus architecture of which, with a creeping, runner-like stolon and numerous pinnate fronds, broadly resembles that of the living bryopsidalean alga Caulerpa. In broader terms, these new algal-Lagerstätten indicate that for a brief time during the late Llandoverian, as with other times during the Silurian, unusual conditions conducive to both the proliferation and preservation of expansive ‘seaweed meadows’ were established across regional-scale areas of the Laurentian epeiric sea.