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Rates of speciation and extinction are often linked to many ecological factors, traits (emergent and nonemergent) such as environmental tolerance, body size, feeding type, and geographic range. Marine gastropods in particular have been used to examine the role of larval dispersal in speciation. However, relatively few studies have been conducted placing larval modes in species-level phylogenetic context. Those that have, have not incorporated fossil data, while landmark macroevolutionary studies on fossil clades have not considered both phylogenetic context and net speciation (speciation–extinction) rates. This study utilizes Eocene volutid Volutospina species from the U.S. Gulf Coastal Plain and the Hampshire Basin, U.K., to explore the relationships among larval mode, geographic range, and duration. Based on the phylogeny of these Volutospina, we calculated speciation and extinction rates in order to compare the macroevolutionary effects of larval mode. Species with planktotrophic larvae had a median duration of 9.7 Myr, which compared significantly to 4.7 Myr for those with non-planktotrophic larvae. Larval mode did not significantly factor into geographic-range size, but U.S. and U.K. species do differ, indicating a locality-specific component to maximum geographic-range size. Non-planktotrophs (NPTs)were absent among the Volutospina species during the Paleocene–early Eocene. The relative proportions of NPTs increased in the early middle Eocene, and the late Eocene was characterized by disappearance of planktotrophs (PTs). The pattern of observed lineage diversity shows an increasing preponderance of NPTs; however, this is clearly driven by a dramatic extinction of PTs, rather than higher NPT speciation rates during the late Eocene. This study adds nuance to paleontology's understanding of the macroevolutionary consequences of larval mode.

New Zealand Cenozoic records of the warm‐water volutid genera Athleta and Lyria are reviewed. Six species of Athleta in two species‐groups are recognised: A. lata (probably Waipawan or Mangaorapan, Early Eocene), Athleta n. sp. A (Mangaorapan (?), late Porangan or early Bortonian, Middle Eocene); A. necopinata (Bortonian), A. marwicki n. sp. (Bortonian), A. taikoensis n. sp. (Mangaorapan to late Porangan or earliest Bortonian), and A. mimica n. sp. (Bortonian). Most species have a short recorded stratigraphic range and are therefore potentially useful for zonation. Athleta is not known after the Bortonian in New Zealand, and may have become locally extinct in response to a cooling episode. Volutospina (Athleta) huttoni pseudorarispina is synonymised with V. (Athleta) huttoni (both Altonian, Early Miocene). V. huttoni and other large Neogene volutes currently assigned to Mauira are transferred to Alcithoe. Athleta (Athleta) wangerrip (Paleocene, Victoria) is transferred to the subgenus Ternivoluta...

Subgenus Volutospina Newton, 1906 Type species. Conus spinosus Linnaeus, 1758 (Middle Eocene, Paris Basin, France) by original designation., Published as part of Merle, Didier, Pacaud, Jean-Michel, M��tais, Gr��goire, Bartolini, Annachiara, Lashari, Rafiq A., Brohi, Imdad A., Solangi, Sarfraz H., Marivaux, Laurent & Welcomme, Jean-Loup, 2014, Volutidae (Mollusca: Gastropoda) of the Lakhra Formation (Earliest Eocene, Sindh, Pakistan): systematics, biostratigraphy and paleobiogeography, pp. 101-138 in Zootaxa 3826 (1) on page 118, DOI: 10.11646/zootaxa.3826.1.3, http://zenodo.org/record/228537, {"references":["Newton, R. B. (1906) Note on Swainson's genus Volutilithes. Proceedings of the Malacological Society of London, 7 (2), 100 - 104.","Linnaeus, C. (1758) Systema naturae per regna tria naturae, secundum classes, ordines, genera, species, cum characteribus, synonymis, locis. Tomus I. Editio decima reformata. Laurentii Salvii, Holmiae, 824 pp. http: // dx. doi. org / 10.5962 / bhl. title. 542"]}

The genus Athleta Conrad 1853 is briefly discussed and the following are regarded as synonyms; Volutocorbis Dall 1890, Volutopupa Dall 1890, Neoathietu Bellardi 1890, Volutospina Newton 1906, Notoplejona Marwick 1926, Eoathleta Gardner 1945, Volutovetus Pilsbry and Olsson 1954 and Bendelutu Eames 1957. Ternivoluta Martens 1897 is regarded as a subgenus of Athleta, and Austrovoluta Cotton 1949 is shown to be a synonym of the former. Ternivoluta is restricted to Australia and ranges from Upper Eocene to Recent. A lineage in the subgenus from Upper Eocene to Upper Miocene is reported. A. (Athleta) wangerrip (Upper Paleocene), A. (Ternivoluta) curvicostata (Upper Eocene), A. (T.) anticingulata craticula (Lower Miocene), A. (T.) subcrenulifera (Lower Miocene) and A. (T.) bungae are newly described from Victoria, Australia and five other species and subspecies are redescribed.