The following papers are in review or else closest to being finished and submitted. (And some at the end have made their way to publication.)

Trilobite sclerite ratios

• Adrain, J.M., and Westrop, S.R. (In prep) Testing for taphonomic overprint of ecological parameters in deep time with trilobite sclerite ratios.

A pilot study using over 17,000 trilobite sclerites from the Lower Ordovician House Formation in western Utah, in an attempt to demonstrate that trilobite head/tail ratios can be used to assess the interplay of ecological taxon-abundance structure and taphonomic distortion in the Lower Paleozoic.

Fig. 2Fig. 3

Status: In review.

Atlanticalymene n. gen. and Protocalymene

• Adrain, J.M., and Karim, T.S. (In prep) Atlanticalymene, a new genus of Middle Ordovician (Darriwilian) calymenine trilobites, and revision of the calymenoidean genus Protocalymene.

The Table Cove Formation of western Newfoundland has yielded spectacular silicified faunas in outcrops in the Hare Bay Region. The first of these projects to come to completion will describe a new calymenid genus, known previously from scraps illustrated from the Dapingian of the Great Basin. These had previously been assigned to Protocalymene Ross, 1967. In 2012 we sampled Ross's fauna in the Funeral Mountains in Death Valley National Park. Protocalymene doesn't seem to have anything much to do with Atlanticalymene and it is questionable whether it is even a calymenine. This seemed like the best place to present a full revision of Ross's taxon based on rich new silicified collections.

Figure 3Figure 4Figure 7Figure 8

Status: Finishing plates and description of Protocalymene mcallisteri Ross.

Silurian calymenids from New York and Ontario

• Adrain, J.M., Edgecombe, G.D., Kloc, G.J. and Tetreault, D.K. (In prep) The Early Ordovician (Floian) bathyurid trilobite genera Jeffersonia, Cullisonia, and Bathyurina.

Based around beautiful new material from the Rochester Shale, this paper sounds the death knell for Spathacalymene Tillman, 1960 (it's a synonym of Diacalymene), restricts Diacalymene to a putative clade, and names the new Rostratocalymene for a Llandovery clade with Calymene schucherti Twenhofel, 1928, as type. Includes a cladistic analysis of Diacalymene s.s., Tapinocalymene, Rostratocalymene, and Dekalymene, using Gravicalymene jugifera as outgroup.

Plate 01 - Calymene microps n spPlate 02 - Calymene microps n spPlate 08 - Diacalymene rochesterensis n spPlate 10 - Diacalymene bairdi n sp

Status: Plates, descriptions, and analysis finished, final writing in progress. We started this project in 1994. Gerry Kloc has announced that I have a 20 year time limit. So okay. Up here it goes.

Brackebuschia, Agerina, and the styginid Subfamily Phillipsinellinae

• Karim, T.S. and Adrain, J.M. (In prep) The phylogenetic affinity of the Ordovician trilobite genera Agerina and Brackebuschia, with new species from Laurentia.

Brackebuschia, Agerina, and their synonyms have generally come to be considered leiostegiids. New silicified material from the Darriwilian Table Cove Formation of western Newfoundland reveals early ontogeny that indicates unambiguous phylogenetic relationship with phillipsinelline styginids. Initially we thought we had unravelled a piece of the "cryptogenesis" puzzle and revealed a link between the leiostegiids and styginids. Now we are gravitating toward the position that the evidence for a relationship with Leiostegiidae is…scant. Oh well. At least we figured out what this group actually is. New species from the Table Cove Formation and Shallow Bay Formation are described, and some previously described species from elsewhere in Laurentia are revised. As far as we can tell, the Cambrian Bellaspidella parallela Ludvigsen and Westrop, 1989, belongs, and it is revised. We also revise other species of Bellaspidella, which is assigned to Dokimocephalidae.

Plate 01 - Brackebuschia idoli n sp APlate 05 - Brackebuschia idoli n sp CCPlate 06 - Brackebuschia adamanti n sp APlate 11 - Agerina boygeorgei n sp

Status: Plates and descriptions finished, final writing in progress.

Graduates (accepted or published):


• Adrain, J.M., Karim, T.S., and Westrop, S. R. (In revision) The Early Ordovician (Floian) bathyurid trilobite genera Jeffersonia, Cullisonia, and Bathyurina.

Another in the series of works detailing the "Acidiphorus group" bathyurids. Full revision of the zonal name bearer Bathyurina plicolabeona and description of four new formally named species. 19 plates of trilobites.

Plate 02 - Strigigenalis plicolabeona (Young, 1973) cranidia librigenae segmentsPlate 04 - Strigigenalis plicolabeona (Young, 1973) pygidiaPlate 11 - Strigigenalis sumneri n sp librigenaePlate 15 - Strigigenalis hooki n sp cranidia

Status: In press.

Ordovician trilobite distributions

• Adrain, J.M. (in press) A synopsis of Ordovician trilobite distribution and diversity. In: Harper, D.A.T. & Servais, T. (Eds.), Early Palaeozoic Palaeobiogeography and Palaeogeography. Geological Society, London, Memoirs, 38, 293–332.

A book chapter which reviews Ordovician distribution at the species level using my database. The bulk of the chapter is comprised of brief narrative accounts of each trilobite family occurring in the Ordovician.

Diversity by Continent
Trilobite species richess (Y axis) by major time slice and continent/terrane through the Ordovician.

Species richness of Encrinurinae by major continent through the Ordovician. Similar plots have been made for all Ordovician families.

Status: Published 2013.


• Adrain, J.M. McAdams, N.E.B. & Karim, T.S. (2012) The Middle Ordovician (Dapingian and Darriwilian) bathyurid trilobite Pseudoolenoides.

The first paper we finished together since Talia joined as a full member of the Great Basin research team. We revised all known species of Pseudoolenoides, named three new ones, carried out a cladistic analysis of the genus, and extended the trilobite zonation through the Dapingian and lower Darriwilian. 30 full plates of trilobites.

Plate 17 - CP 160' Pseudoolenoides acicaudus Hintze, 1953 APlate 29 - Pseudoolenoides carterensis AA copyPlate 27 - K 524' Pseudoolenoides fossilmountainensis n sp CPlate 11 - P dilectus holotype copy
Figure 02 - Zone Chart
Figure 03 - cladogram

Status: Published 2012.