Crassivitisemen

Name

Crassivitisemen

Rank

Genus

Authors (Pub.)

Collinson M. E. Manchester S. R. Wilde V.  

Publication

Fossil fruits and seeds of the Middle Eocene Messel biota, Germany [2012/6]

Journal

Abhandlungen [herausgegeben von] der Senckenbergischen Naturforschenden Gesellschaft

Volume

570

Page number

55

Year

2012

Parent Taxon

[Family] Vitaceae

Fossil Status

fruits (with seeds)

Type

Crassivitisemen wildei

Diagnosis

Fruit single-seeded, obovoid, bilaterally symmetrical, narrowly rounded basally, broadly rounded apically, but with a central apical depression giving a cordate appearance, 16–23 mm long, 11.5–13 mm wide, 6.5–8 mm thick. Fruit relatively irregularly rugulate to verrucate with a median longitudinal rib (vascular strand) on one face and a rounded basal scar. Pericarp 1.5 mm thick, composed of somewhat spongy tissue (but not much compacted in preservation due to rigid cell walls) of isodiametric cells. Epicarp a thin outer cuticle with isodiametric cells, hexagonal in surface view, 30–40 μm diameter. Epicarp surface slightly shiny and with slightly raised outer periclinal walls appearing like small papillae when well preserved. Mesocarp with thick outer layer of open thin-walled parenchymatous tissue and thinner inner layer of more compact tissue. Seed oval to pyriform in ventral or dorsal view, large, 11–14 mm long, 7–9 mm wide, dorsiventral thickness uncertain because of compression of the fossils. Apical notch and beak not prominent. Ventral surface smooth; ventral infolds linear, parallel to slightly divergent from each other, and about one-half to two-thirds of the full seed length. Dorsal surface rugose, with 7–8 pairs of ridges radiating out from the edge of the elongate oval chalaza. Chalaza located at the centre of the dorsal surface elongate, and about one-third of the full seed length. Chalaza-apex and base grooves present, linear. Seed coat very thick (1.2 mm), composed of nearly isodiametric cells aligned in anticlinal rows.