Crepetocarpon

Na, Yuling, Blanchard, Jane & Wang, Hongshan, 2019, Fruits, seeds and flowers from the Puryear clay pit (middle Eocene Cockfield Formation), western Tennessee, USA, Palaeontologia Electronica (a 49) 23 (3), pp. 1-57 : 24

Crepetocarpon perkinsii (Berry) Dilcher and Manchester, 1988

Figure 27

1988 Crepetocarpon perkinsii (Berry) Dilcher and Manchester, figs. 1–10, 15–21, 24, 26–34, textfig. 1A, B; pp. 45–57.

1922 Monocarpellites perkinsi Berry , pl. 16, fig. 1–6, p. 16.

Description. Vertically compressed fruit ca. 1.8 cm x 1.4 cm (part) with eight radially arranged units around a ca. 2 mm diameter central column.

Number of specimens examined. 1. UF15820- 059480, 059480’.

Remarks. Dilcher and Manchester (1988) examined 75 specimens collected from the Richies Black (UF15828), Lawrence (UF15816), New Lawrence (UF15818), and Miller (UF15817) localities in Henry Co., Tennessee, and two specimens reported by Berry (1922), also from Henry Co., Tennessee. Based on the striking similarities between the fruits of Crepetocarpon and extant Hippomane mancinella , they proposed that this fossil genus and species be assigned to the Euphorbiaceae (tribe Hippomaneae ). These similarities include fruits consisting of comparable number of carpels, anatropous ovules, and each locule containing one seed embedded in a fibrous endocarp which is in turn covered by a mesocarp and an epidermal exocarp, They established the fossil genus because of major differences between the fossil and extant Hippomane fruits in margins of the endocarp rays (smooth vs. scalloped), mesocarp parenchyma cells (thick-walled vs. thin-walled), number of locules, fruit size, and tegmen thickness (150 µm vs. 25 µm).

Figures

FIGURE 27. Crepetocarpon perkinsii (Berry) Dilcher and Manchester, 1988, UF15820-059480, compressed fruit with radiating ridges. Scale bar equals 2 mm.