Bursa Roding 1798
Creators: name: Sanders, Malcolm T.
name: Merle, Didier
name: Puillandre, Nicolas
Publisher: name: Zenodo
Year: 2019
Subjects: Biodiversity
Taxonomy
Animalia
Mollusca
Gastropoda
Littorinimorpha
Bursidae
Bursa

description: TACKLING BURSA IN THE FOSSIL RECORD
As currently understood, Bursa Röding, 1798 is very morphologically variable, so variable in fact that Beu (1998: 143) gave the broad generic description that “ Bursa is a large genus containing species with short to tall spires, weak to coarse sculpture, heavy and thick to light, thin shells, with varices variable in position […] and with or without a red colour area on the parietal lip”. One conclusion may be that Bursa is a “trash” genus, and exists only to classify species that do not fit anywhere else (this status was confirmed by Castelin et al. 2012 [Fig. 4] and Strong et al. 2018). Being paraphyletic (or polyphyletic), such genera are an impediment for every systematist aiming to describe biodiversity in its historical dimension (Faurby et al. 2016).
To our knowledge there are 14 recognized extinct species of Bursidae, two-thirds of them referred to Bursa (Bursa amphitrites Maury, 1917, B. chipolana Schmelz, 1997, Ranella grateloupi d’Orbigny, 1852, Apollon inaequicrenatus Cossmann & Peyrot, 1924, B. sangirana Beu, 2005, R. tuberosa Grateloup, 1833, B. victrix Dall, 1916, R. morrisi d’Archiac & Haime, 1853 and B. landaui Harzhauser, 2009) and the rest to Marsupina Dall, 1904 (Bursa chira Olsson, 1930, Bursa (Marsupina) freya Olsson, 1932, Bursa chira var. yasila Olsson, 1930, Marsupina judensis Beu, 2010, and Gyrineum strongi Jordan, 1936).
Following Beu’s (1988, 2010) opinion we consider Marsupina freya, M. judensis and M. strongi to be correctly attributed to the extant genus Marsupina.
As we want Bursa to be monophyletic, based on the phylogeny of Castelin et al. (2012) and considering the position of the type species of the genus (B. bufonia (Gmelin, 1791)), we end up with a narrower definition of Bursa; it contains only B. bufonia and B. lamarckii (Deshayes, 1853), to which we can add B. luteostoma (Pease, 1861), B. rosa (Perry, 1811) and B. tuberosissima (Reeve, 1844), on the basis of their tubular and elongated posterior siphonal canal.
None of the fossil species mentioned above are closely similar to Bursa bufonia and none of them are type species of a previously published name that could be resurrected. So we are left with two options: either erect new genera (as few as possible) or propose phylogenetic hypotheses linking fossils with extant species (preferably type species).
Bursa sangirana Beu, 2005 (Fig. 5E), from the late Pliocene Kalibeng layers (Sangiran, central Java), has a low spire with a warty ornamentation. Its posterior siphonal canal is short; it is very reminiscent of Bursa rhodostoma (G. B. Sowerby II, 1835) (Fig. 3F) and is probably closely related to it. Both species may be included in the separate genus Lampadopsis Jousseaume, 1881 for which B. rhodostoma is the type species. The resurrection of this genus was suggested recently by Strong et al. (2018).
Bursa landaui Harzhauser, 2009 (Fig. 4C, D): this slender shell is only known by two external molds from the Aquitanian of Ras Tipuli, Lindi Bay, Tanzania. It has a very fine granulose ornamentation and a weakly expressed shoulder, slightly reminiscent of Bursa granularis (Röding, 1798) (Fig. 3G) and similar to Bursa condita (Fig. 3A). This may be an indication of the close relationship of the three species, for which there are two or possibly three available generic names: Colubrellina Fischer, 1884 and Dulcerana Oyama, 1964. Bufonariella Thiele, 1929 is possibly another available name considering the close resemblance of its type species, Bursa scrobilator (Linnaeus, 1758), to B. granularis.
Bursa victrix Dall, 1916: this species is only known from a poorly preserved external mold (USNM 166728) from the late Oligocene of Mascot Point, Flint River, Georgia, United States. The almost evenly inflated whorl profile, with a slightly protruding shoulder angle formed by a row of rounded nodules at approximately the upper third of the whorl height on the spire, the numerous lower rows of nodules extending down over the anterior canal, and the deeply buttressed abapertural face of the varix on the ultimate whorl are all characters in common with Bursa corrugata (Perry, 1811) (Fig. 3D). We follow Beu’s (2010) opinion, keeping it as a species separate from B. corrugata pending the discovery of better-preserved specimens.
Among the remaining extinct bursid species, two are strikingly similar: Marsupina chira (Olsson, 1930) and M. yasila (Olsson, 1930), for which we propose a new genus, Olssonia n. gen.
In the same fashion, Bursa amphitrites Maury, 1917, B. grateloupi (d’Orbigny, 1842), B. inaequicrenata (Coss- mann & Peyrot, 1923), B. tuberosa (Grateloup, 1833), Bursa chipolana Schmelz, 1997, and Ranella morrisi d’Archiac & Haime, 1853 are here attributed to a new genus: Aquitanobursa n. gen. These new genera are described below.
Bursa s.s.
tenuigranosa rubeta ranelloides latitudo rhodostoma granularis lamarckii bufonia gnorima nobilis perelegans quirihorai fijiensis fosteri awatii
Tutufa Tutufa Bursa Bursa Bursa Bursa Bursa Bursa Bursina Bursina Bufonaria Bursa Bursa Bursa Bursa
description: Published as part of Sanders, Malcolm T., Merle, Didier & Puillandre, Nicolas, 2019, A review of fossil Bursidae and their use for phylogeny calibration, pp. 247-265 in Geodiversitas 41 (5) on pages 252-254, DOI: 10.5252/geodiversitas2019v41a5, http://zenodo.org/record/3699932