Ulmus affinis

Denk, Thomas, Sami, Marco, Teodoridis, Vasilis & Martinetto, Edoardo, 2022, The Late Early Pleistocene Flora Of Oriolo, Faenza (Italy): Assembly Of The Modern Forest Biome, Fossil Imprint 78 (1), pp. 217-262 : 230-232

Ulmus affinis A.MASSAL., 1853

Text-fig. 6f–l

1853 Ulmus affinis A.MASSAL., p. 19.

1854 Ulmus affinis A.MASSAL.; Massallongo, p. 19, pl. 4, fig. 8.

1858 Ulmus affinis A.MASSAL.; Massallongo, p. 41.

1859 Ulmus affinis A.MASSAL.; Massallongo and Scarabelli, p. 212.

1859 Ulmus braunii HEER ; Massalongo and Scarabelli, p. 211, pl. 21, fig. 10.

2001 Ulmus cf. pyramidalis GÖPP. ; Martinetto and Sami, p. 17, fig. 7.

2003 Ulmus affinis A.MASSAL.; Martinetto, p. 102, pl. 8, figs 2–4 (not fig. 1 = U. pyramidalis GÖPP. ).

M a t e r i a l. MSF 637, 705, 717, 718, 719, 720, 721,

722, 723, 724, 725, 726, 786.

D e s c r i p t i o n. Leaf simple, petiolate, lamina elliptical, elliptical-lanceolate, commonly asymmetrical, lamina 19– 64 mm long, 14–34 mm wide, length to width ratio ca. 2/1 to>4/1, apex acute, acuminate, base strongly asymmetrical, acute to cordate-auriculate, secondary venation craspedodromous, usually at least some secondary veins splitting halfway or close to lamina margin, margin serrate, teeth double serrate, the secondary tooth commonly inconspicuous.

R e m a r k s. Ulmus leaves are very common in the late Cenozoic of Europe, and their taxonomy has been confusing. In the nineteenth century, numerous fossil-species were established (e.g., Göppert 1855). The leaves from Oriolo agree well with Unger’s type U. longifolia UNGER, 1847 . This taxon is problematic, as the name U. longifolia UNGER is illegitimate (younger homonym). The same name had previously been used for the modern species U. longifolia RAF., 1838 . To solve this problem, Knobloch (1969) included U. longifolia in Ulmus pyramidalis GÖPP., 1855 . However, in the emended description of U. pyramidalis , the leaf base is described as weakly asymmetric, and the original specimens of Göppert’s (1855) U. pyramidalis have a symmetrical lamina with a symmetrical or weakly asymmetrical leaf base. The base is described as rounded or cuneate, rarely asymmetric by Hably and Zastawniak (2001), who consider the most characteristic features of U. pyramidalis the densely spaced secondary veins, particularly in the upper part of the lamina, and the regular shape. Hence, in our opinion, U. longifolia UNGER nom. illeg. considerably differs from U. pyramidalis and should not be synonymised with the latter. The former would need a replacement name and a new taxonomic, geographic, and stratigraphic circumscription.

The similarity of U. affinis with U. longifolia was also noticed by Massalongo (1854) and Massalongo in Massalongo and Scarabelli (1859: 213). In the latter work, Massalongo noted that some specimens of Ulmus braunii HEER from Öhningen should be included within U. affinis , and that the name U. braunii possibly would need to be treated as junior synonym of U. affinis . He further was uncertain as to how to distinguish the specimens from Sośnica (Schossnitz), figured by Göppert (1855) as U. longifolia , from Ulmus affinis . In the present investigation, we include in U. affinis Messinian material from Senigallia, Pliocene material from Northwestern Italy ( Martinetto 2003), and the present late Early Pleistocene material (App. I, Text-fig.A1 ). More work is needed to resolve the question of whether the lineage leading to U. affinis from Oriolo dated back to the Late Miocene (as in the concept of the present study), or whether it dated back to the Early Miocene ( U. longifolia of Bílina).

According to Webenau (1995), the shape of leaves traditionally assigned to U. longifolia has no analogues in the current European flora, and the living species with the most similar leaves are U. castaneifolia HEMSL., 1891 , and U. lancifolia ROXB., 1814 , both from East Asia. Ulmus lancifolia , although somewhat similar in shape (elongate apex, narrow leaves), differs by its evergreen foliage, simpleserrate margin, and weakly asymmetrical leaf base (App. I, Text-fig. A2 ). Leaves with a distinctly asymmetrical leaf base and elliptic-lanceolate shape are found in a clade of western Eurasian species of sect. Ulmus ( Wiegrefe et al. 1994) : Ulmus glabra HUDS., 1762 , U. minor MILL., 1768 , and their hybrids, e.g., U. × hollandica MILL., 1768 (App. I, Text-fig. A2 ), as well as in the Caucasian U. elliptica K.KOCH, 1849 .

Figures

Text-fig. 6. a: cf. Rubus sp., leaflet Oriolo MSF 676. b, c: cf. Sorbus. b: Oriolo MSF 821. c: MSF 677. d: Spiraea aff. cana Oriolo MSF 944. e: Rhamnus aff. cathartica Oriolo MSF 909. f–l: Ulmus affinis. f: Oriolo MSF 717. g: Oriolo MSF 725. h: Oriolo MSF 724. i: Oriolo MSF 721. j: Oriolo MSF 723. k: Oriolo MSF 637. l: Oriolo MSF 722. m: Zelkova zelkovifolia Oriolo 28 MSF 633. Scale bars 10 mm (a–f, m), 50 mm (g–l).

Text-fig. 1. a: Po Plain and foothills of the Northern Apennine in Northern Italy (inset) with the location of Oriolo (black star) and other Earlyand Middle Pleistoceneplant localities, Enza and Stirone. Red lines indicate the frontal thrust arcs (modified from Martinetto et al. 2015). b: The “La Salita” section, Oriolo and chronology of the two “Sabbie gialle” cycles based on large mammals and palaeomagnetic correlation (modified from Toniato et al. 2017; IMMS 2020* [Italian Mediterranean Marine Stages] updated from Cohen and Gibbars 2020; GTS 2021* [Global Time Scale] updated from Head et al. 2021). c: Quarry “La Salita”, Oriolo, in 1987. Main unconformities (U) separating the two “Sabbie gialle” cycles and terrestrial deposits on top are shown. Leaf symbols indicate the positions of some of the layers rich in fossil leaves (photo by G. B. Vai, modified). d: Surroundings of Faenza with the location of Oriolo and adjacent coeval sites yielding plant macrofossils.

Text-fig. 2. a, b: Pinus aff. peuce cones. a: Oriolo, MSF 643. b: Tebano, MSF 1021. c: Abies aff. alba cone scale, Oriolo MSF 988. d, e: Tsuga chiarugii cones. d: Oriolo MSF 638. e: Oriolo MSF 979. f, h: Bambusa lugdunensis leaves and leafy axis. f: Oriolo MSF 937. h: Oriolo MSF 651. g: Modern leaf of Yushania for comparison (NMNS Cleared Leaf Database specimen U1347). i: Phragmites sp. Oriolo MSF n.n. Scale bars 50 mm (a, b, h, i), 10 mm (c–g).