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The presidential address for The Paleontological Society traditionally has been given on a topic in the president's own special area of research. This year I am breaking that tradition because there are serious matters concerning this Society that deserve widespread discussion.
A benthic foraminiferal fauna of 39 species was quantitatively examined from a late Pleistocene marine terrace deposit near Goleta, California. This foraminiferal fauna, dominated by Cribroelphidium microgranulosum, Buccella tenerrima, Buliminella elegantissima, and Cribroelphidium tumidum, is presently most common in cool, shallow (<12 m, but usually 0–5 m) subtidal environments north of Point Conception, California. This indicates slightly cooler water temperatures during the time of deposition than found near Goleta today, and agrees closely with the results of a previous paleoenvironmental interpretation of the section based on molluscan fossils.
Sixteen genera and 27 species of Recent brachiopods are reported from the far southern Pacific Ocean and adjacent parts of the South Atlantic and southern Indian Ocean. These specimens extend the known geographic ranges of at least 10 species and the known bathymetric ranges of at least seven species. The new material gives greater support to the idea that many Recent brachiopod species have a wide geographic range and calls into question the very limited geographic ranges of many species known only from the fossil record. Puncta density appears to be a useful character for distinguishing Neothyris compressa and N. lenticularis. At least nine different types of geographic distribution are represented among the species studied for this paper. Areas of moderate depth on seamounts, particularly along oceanic ridges and on oceanic rises, may form important geographic areas of distribution, avenues of dispersal, and barriers to brachiopods. Four examples of polytypic species are cited. The new specimens lend additional support to the notion that one polytypic species of Liothyrella extends, with clinal morphological changes, from southernmost South America to Antarctica. Students of modern brachiopods are urged to consider large-scale geographic variation within species and not to hide it with finely delimited taxa. This approach has the potential to lead, in both modern and ancient brachiopods, to a taxonomy with fewer and more meaningful species and genera. Progenetic changes seem to be a common adaptive strategy in brachiopods on largely soft substrates and in deep water. The progenesis may be short term within a single species or long term involving evolution of new species and genera.
Reexamination of collections of North American Hyolitha reveals the presence of several new genera and several taxa previously known only from southeastern Europe and the Soviet Union. New representatives of the family Hyolithidae in North America are Doescherina clarki n. gen. and sp. from the Upper Cambrian of Montana and Grantitheca glenisteri n. gen. and sp. from the Lower Cambrian of New York. The geographic and stratigraphic ranges of Nevadotheca Malinky are extended by placement of Hyolithes excellens Billings from the Lower Cambrian of Newfoundland and H. princeps Billings from the Lower Cambrian of Quebec in that genus, and by the occurrence of the new species N. heckeli in the Upper Cambrian of Tennessee. Diversity within the Hyolithidae is further increased by the discovery of specimens representing a new genus in the Upper Cambrian of Alberta, but that genus remains indeterminate because those specimens are not well preserved.
The type lot of Hyolithes communis Billings from the Lower Cambrian of Quebec is here included under Nitoricornus Syssoiev, to which the species H. impar Ford from the Lower Cambrian of New York is also transferred. Morphology of specimens of Hyolithes quadricostatus Shaler and Foerste from the Lower Cambrian of Newfoundland requires placement under Holmitheca quadricostatus (Shaler and Foerste) and Novitatus mapesi n. sp., family Novitatidae, order Orthothecida. Formerly, Nitoricornus Syssoiev, Holmitheca Syssoiev, and Novitatus Syssoiev were known only from the Soviet Union. These occurrences extend their geographic ranges to North America. The first known representative of the family Pauxillitidae Marek in North America, Neopauxillites zlatarskii n. gen. and sp., extends the range of that family from the Ordovician of Czechoslovakia to the Lower Cambrian of Newfoundland.
Overall poor preservation of type specimens of Hyolithes americanus (Hall), H. gregarius (Meek and Hayden), H. primordialis (Hall), and H. welleri Roy precludes complete diagnoses of these species and confident assignment to genus. Hyolithes americanus and H. welleri are tentatively included under Grantitheca; the other species remain under Hyolithes with question. The names of these species should not be used for new material until better preserved topotypes become available for study.
By the end of the Cretaceous, the Clavagellidae (Mollusca: Pelecypoda) maintained a distribution that was marginal to the core-Tethys, occurring in both North America and the Old World. Traditional paleozoogeographic interpretation contends that the clavagellids then went extinct in the New World because no Cenozoic fossil or living clavagellids have been documented from the Western Hemisphere. This report describes the occurrence of Eocene clavagellids from the Ocala Group of peninsular Florida. The presence of these pelecypods in Upper Eocene strata is consistent with the large Tethyan faunal component already known from this unit and requires a reassessment of Tertiary zoogeographic patterns for the clavagellids.
A new species of teuthid squid, Teudopsis cadominensis, is described from the Toarcian (Lower Jurassic) Poker Chip Shale of the Fernie Formation in central-western Alberta. Fossil squids are rare in the Mesozoic of North America; this species is the first record of the family Palaeololiginidae in North America and the first member of the suborder Mesoteuthina in the Jurassic of North America.
Triangulotarbus terrehautensis n. gen. and sp. is a Pennsylvanian phalangiotarbid (Arachnida) that occurs in the sandy shales of the lower Shelburn Formation, McLeansboro Group, Desmoinesian Series, above Coal VII (Danville Coal) of the Dugger Formation. Triangulotarbus terrehautensis is the youngest phalangiotarbid that has been collected in North America.
Lacertasterias elegans and Schondorfia fungosa are new genera and species of multiarmed asteroids described from the Kinderhookian? (Mississippian) Gilmore City Formation of Iowa and the Chesterian (Mississippian) Haney Formation of Illinois, respectively. Based on ambulacral construction, the former belongs to the Paleozoic asteroid stem group whereas the latter is distinct from but closer to post-Paleozoic asteroids.
The multiarmed condition is atypical today; nevertheless, multiarmed species are morphologically varied and taxonomically widely distributed. The condition is considered problematic; it is uncertain whether or not multiarmed organization is adaptively neutral. Although only convergent with rather than ancestral to post-Paleozoic multiarmed asteroids, both new genera share important similarities with modern multiarmed predators, implying a predatory life mode for the fossils. The similarity between phylogenetically disparate Paleozoic and post-Paleozoic asteroids implies the multiarmed condition is beneficial, and benefits endured in spite of the major biotic changes that occurred around the end of the Paleozoic.
Isolated, uncompressed specimens of Monograptus spiralis show that the thecae become increasingly asymmetric and twisted distally and that the lateral margins of the apertures possess lobate veins and extend laterally as spatulate rostral processes. These too become increasingly asymmetric distally.
Three species of Cyrtograptus, obtained uncompressed from the same and overlying strata, are compared with M. spiralis. They show little similarity in the details of proximal or distal thecal form. Cyrtograptus sakmaricus possesses more stout, overlapping proximal thecae, while those of C. cf. C. laqueus are slender and elongate. In both species, the thecae are moderately asymmetrical, become simpler and less strongly hooked distally, and have simple lateral margins. The third species, Cyrtograptus sp., possesses proximal thecae very like those of C. sakmaricus, but its distal thecae, while strongly twisted, are very much simpler than the type found in M. spiralis.
Despite superficial rhabdosomal similarities in flattened material, the thecal details clearly indicate that M. spiralis is very unlikely to be ancestral to any known species of Cyrtograptus owing to its unique and highly specialized thecal form. Comparison among species of Cyrtograptus suggests, however, that this genus might be polyphyletic, with its ancestors being other members of the “Spirograptus” group.
The platform element of the conodont Amydrotaxis praejohnsoni n. sp. shows statistically significant morphological changes from the base to the top of the delta Zone (Lower Devonian). The changes occur particularly in mean denticle number, height and character of the anterior denticles, and shape of the basal cavity. The earliest forms have fewer denticles ( = 7.1), an enlarged, high anterior denticle, and a broadly flared posterior basal cavity, whereas late forms have more denticles ( = 9.4), equal-sized anterior denticles, and a narrow posterior basal cavity. There is no stasis phase in the species history, but rather a mosaic pattern in which the observed changes in the character states are seemingly independent of each other and proceed at variable rates.
A new species, Enchodus brevis (Enchodontoidei: Enchodontidae), is described from lower Cenomanian beds in Ein-Yabrud, near Jerusalem. The species is characterized by the following features: the shortest enchodontid body; an ectopterygoid bearing one smooth canine terminal tooth; barbed dentary teeth; a huge front tooth of dentary with two anterior cutting edges; two supraneurals; second preural vertebra without a neural spine; and absence of lateral line scales except for a long hook-like terminal scale at the caudal peduncle. The systematic position of the new species suggests the emendment of the generic diagnosis.
Small vertebrates were recovered from the matrix encasing specimens of giant sauropod dinosaurs (Supersaurus, Ultrasaurus, Dystylosaurus) collected from the “Dry Mesa” Quarry (Brushy Basin Member, Morrison Formation, western Colorado). Most of the remains appear to pertain to a single form of pterodactyloid pterosaur, Mesadactylus ornithosphyos, n. gen. and sp., the holotype of which is a synsacrum. A bone end from this quarry, first identified as an avian proximal tibia and named Palaeopteryx thomsoni, is reidentified as the distal radius of a small deinonychosaur or bird. A small femur of a small deinonychosaur or bird and additional material of other small vertebrates from this quarry are figured and described.
An Upper Triassic metaspondyle dasycladacean alga, Diplopora oregonensis n. sp., is described from the Hurwal Formation, southern Wallowa Mountains, northeastern Oregon. It occurs in the accreted Wallowa terrane, which is interpreted as far-travelled relative to the craton of North America. The fossil alga is found in limestone clasts within a limestone–chert–volcanic clast conglomerate of the Hurwal Formation. The new species is related to Diploplora borzai Bystricky, known from the Upper Triassic of the Carpathian Mountains and Sicily, but is distinguished by very small branches and a distinct segmentation of the thalli. Diplopora oregonensis is the first Triassic dasycladacean alga known from the United States, and perhaps from all of North America. The absence of calcareous green algae from rocks of cratonal North America, as well as from most Triassic displaced terranes of the eastern and western Pacific, is in stark contrast to counterparts in the former Tethys region of central Europe, where dasycladacean algae were abundant and contributed significantly to the sediment. This paucity of algae may be related to differences in environment, but more likely is linked to the paleogeographic situation and dispersal abilities of the algae. The similarity of the Oregon dasyclads to species in western Europe, coupled with the lack of dasyclad algae in any other part of North America, is evidence in support of a far-travelled nature for the Wallowa terrane.
In his monograph on the fauna of the Utica and Lorraine Formations of New York, Ruedemann (1925b) described a new and unusually young species of Corynoides, C. ultimus. He obtained these specimens from a thin band within the Utica Shale at a locality on Ohisa Creek (a tributary of the more well known Nowadoga Creek) in the Mohawk Valley. Like many of the graptolites from the Utica, the Corynoides ultimus specimens are vague carbon films, extensively exfoliated and difficult to study. Perhaps consequently, Ruedemann's illustrations and measurements are not entirely accurate and do not reveal sufficient detail for meaningful comparison of this taxon with other, better known species.
The ichnogenus Didymaulichnus has previously been reported in rocks of upper Precambrian-Carboniferous age (Häntzschel, 1975; Pickerill et al., 1984). Didymaulichnus has been postulated by different authors to be an epistratal grazing trace of trace makers ranging from molluscs and other soft-bodied animals to arthropods (Young, 1972; Häntzschel, 1975; Bradshaw, 1981; Hakes, 1985). If this is the case, it is reasonable to assume Didymaulichnus occurs in sediments and sedimentary rocks that are as young as the modern. In an examination of the Cardium Formation (Upper Cretaceous, Turonian) this ichnogenus occurred with relative abundance.
Trace fossils figured in four recent papers in the Journal of Paleontology and Palaios have been reposited in the Invertebrate Paleontology Collection of the Cleveland Museum of Natural History (CMNH). Catalog numbers for these specimens are herein assigned.
The collections of A. E. Reuss were missing for a long period of time. When they were rediscovered they were stored in the Museum of Natural History in Vienna. The associated catalog is still missing. Since many of the Cretaceous foraminifers described by Reuss are assumed to be widespread around the world, it is desirable to have his original material as a reference when classifying the specimens found in drillings and natural exposures. As quite a lot of them are usable as index fossils, they are of special value in the exploration for oil and gas.