Lanfrancia subglobosa E.REID et M.CHANDLER, 1933

Manchester, Steven R. & Collinson, Margaret E., 2022, Mastixioid Fruits (Cornales) From The Early Eocene London Clay Flora: Morphology, Anatomy And Nomenclatural Revision, Fossil Imprint 78 (1), pp. 310-328 : 321

Lanfrancia subglobosa E.REID et M.CHANDLER, 1933

Text-fig. 8a–o

R e m a r k s. Lanfrancia was distinguished by Reid and Chandler (1933) from Exbeckettia (then Beckettia ) in lacking the large wedges of parenchymatous tissue between locules. In addition, the fruits of Lanfrancia do not show the obvious pair of ovular traces adjacent to each locule – a difference from extant and fossil Mastixia , as well as from Exbeckettia and Eomastixia . Three to five layers of horizontal fibres line the U- to V- or C-shaped locules of Lanfrancia (e.g., Textfig. 8k, m), but the remainder of the endocarp is formed by rounded sclereids as seen in transverse section ( Text-fig. 8j–m ) and longitudinal section ( Text-fig. 8n, o ).

Reid and Chandler (1933) noted the similarity of Lanfrancia to Eomastixia , but considered that it differed by having more locules. Later this difference was negated as Chandler (1962) showed that 3- and more-loculed fruits of Eomastixia occur at the type locality ( Manchester and Collinson 2019). Reid and Chandler also noted a possible difference in mode of germination. The Lanfrancia specimens were observed to fall apart into pyrenes, rather than staying together and germinating by valves – a feature they acknowledged could be due to their pyritic preservation, differing from the carbonaceous preservation of the type material of Eomastixia . Lanfrancia corresponds to Eomastixia in the fibrous composition of the septa and dorsal infold regions, the closed dorsal infolds (with little or no intrusion of mesocarp). Whereas Eomastixia includes resin cavities ( Collinson et al. 2012, Manchester and Collinson 2019), we have not observed these in Lanfrancia .

Figures

Text-fig. 8. Lanfrancia subglobosa E.REID et M.CHANDLER. a–c, e–g: Holotype V. 23014. a: reflected light. b, c: Surface renderings from micro-CT data. a, b: Lateral views with dorsal surface of locule facing forward and locule casts protruding in upper part. c: Apical view. d: Fruit showing two locule casts the dorsal surfaces of which face to the left and the right, V. 30417(1). e–g:Successive digital transverse sections showing four u to v to c-shaped locules from micro-CT data. h: Physical transverse section of specimen in (d). i–k: Physical transverse section, V. 30419 from Herne Bay, blue lines in K indicating limits of fibre layer lining the locule. l: Detail from (h), showing sclerenchyma composing the septa and central axis. m: Transverse section, enlargement from (i), showing anatomy of tissues adjacent to the dorsal infold. Blue lines indicate limits of the fibre layer lining the locule. n: Part of (m) recut, tangential section transecting the dorsal infold (central), both limbs of the locule cast, and peripheral parts of the pericarp on either side. o: Detail from (n), showing anatomy of the infold. Scale bars 5mm in (a–h) (a–g share the same bar), 3mm in (i), 1mm in (j–m), 0.5mm in (n), 0.2mm in (o).