Mastixioid Fruits (Cornales) From The Early Eocene London Clay Flora: Morphology, Anatomy And Nomenclatural Revision Author Manchester, Steven R. Author Collinson, Margaret E. text Fossil Imprint 2022 2022-08-26 78 1 310 328 http://dx.doi.org/10.37520/fi.2022.013 journal article 10.37520/fi.2022.013 2533-4069 7167911 Mastixia cf. oregonensis (R.A.SCOTT) TIFFNEY et HAGGARD, 1996 Text-fig. 4a–i 1954 Mastixioidiocarpum oregonense R.A.SCOTT , p. 84, pl. 16, figs 16–18. 1994 Mastixioidiocarpum oregonense R.A.SCOTT ; Manchester , p. 43, text-fig. 10B, pl. 10, figs 4–11. 1996 Mastixia oregonensis (R.A.SCOTT) TIFFNEY et HAGGARD , p. 42, pl. 2, figs 1–3. R e m a r k s. Although the holotype that Reid and Chandler (1933) designated for Mastixia cantiensis belongs instead to Diplopanax (see above), some of the paratypes they identified to Mastixia cantiensis are readily distinguished from Diplopanax in having prominent endocarp sculpture and a pair of prominent ovular bundle canals in the endocarp adjacent to the germination valve margins. In particular, the specimens V. 22955 ( Reid and Chandler 1933 : pl. 25, fig. 4), V. 22960(1) ( Text-fig. 4a–c ), and V. 22963(2) ( Text-fig. 4e–f ) resemble the fossil genus Mastixioidiocarpum R.A.SCOTT , previously described from the Eocene Clarno Formation of Oregon , USA ( Scott 1954 , Manchester 1994 ). That fossil genus was subsumed into Mastixia by Tiffney and Haggard (1996) , who noted that the only difference from modern species of the genus is the more prominently sculptured endocarp. Tiffney and Haggard (1996) also attributed similar fruits from the late Eocene LaPorte flora of California to the extant genus. A clear distinction between the Oregon species and the London Clay specimens has not been seen, but the London Clay specimens typically show less prominent sculpture due to abrasion. We treat specimens of this kind as Mastixia cf. oregonensis . In Europe, such prominently sculptured fossil endocarps are present in some species of Eomastixia but are rare in Mastixia . Most similar are Mastixia thomsonii MAI from the Miocene of Konzendorf and Düren, Germany ( Mai 1970 ) and M. rattazzii MARTINETTO ( Martinetto 2011 ) from the Oligocene of Germany and Italy , respectively.