Protomimosoidea buchananensis Crepet and Taylor, 1986

Blanchard, J, Wang, H & Dilcher, D, 2016, Fruits, seeds and flowers from the Bovay and Bolden clay pits (early Eocene Tallahatta Formation, Claiborne Group), northern Mississippi, USA, Palaeontologia Electronica 19 (3), pp. 1-59 : 9-12

Protomimosoidea buchananensis Crepet and Taylor, 1986

( Figures 5 , 6 , 7 )

* 1986 Protomimosoidea buchananensis Crepet and Taylor , p. 555, figs. 1-22.

v. 2013 Protomimosoidea buchananensis Crepet and Taylor ; Wang, Blanchard, and Dilcher, p. 15, fig. 12.

Description. Flowers ca 3–4 mm long and 2–4 mm wide (excluding filaments and pedicel) with up to 10 stamens. Filaments exserted, up to 5 mm long and often of unequal length. Anthers ca 0.75–1 mm long and 0.5 mm wide. Perianth parts usually three, triangular, ca 2 mm long, and 1 mm wide, attached to the rim of the receptacle. Receptacle ca 2 mm wide and 1 mm long. Pedicel ca 0.3 mm wide and up to 6 mm long.

Number of specimens examined. 4. UF15737- 026430, 027593, 060709.

Remarks. Flowers of Protomimosoidea buchananensis Crepet and Taylor, 1986 are common from the Warman, Puryear and Buchanan localities of the Claiborne Group in Tennessee ( Crepet, 1979; Crepet and Taylor, 1985, 1986; Wang et al., 2013). Compared with flowers from other Claiborne localities, specimens from the Bovay locality are better preserved and they are probably more mature than those described from the Warman locality. One complete flower ( Figure 5 ) has 10 stamens, five of which have shorter filaments that are only 67% of the length of the other five stamens.

Berry (1916b, p. 322, plate 96, figures 1-5) described a similar flower from a locality 2.4 km west of Grand Junction in Fayette County, Tennessee. He suggested that this specimen, assigned to Combretanthites eocenica , is closely related to the Combretaceae rather than the Mimosoideae because of its inferior ovary. If, however, the ovary is superior within a hypanthium, Berry’s specimen could belong in Protomimosoidea . Crepet and Taylor (1986) did not include Berry’s specimen in their study of primitive mimosoid flowers. Unfortunately, we are unable to locate the specimen described by

BLANCHARD, WANG, & DILCHER: FOSSIL PLANTS FROM MISSISSIPPI

Berry (1916b) to further confirm or reject its assignment to the Combretaceae .

Figures

FIGURE 5. Protomimosoidea buchananensis Crepet and Taylor, 1986, UF15737-026430. Flower showing at least three valvate petals, 10 stamens, and dorsifixed anthers. Note two stamens with missing anthers (indi- cated by arrows). Scale bar equals 0.5 mm.

FIGURE 6. Protomimosoidea buchananensis Crepet and Taylor, 1986, UF15737-060709. Specimen showing three petals and five stamens. Scale bar equals 0.5 mm.

FIGURE 7. Protomimosoidea buchananensis Crepet and Taylor, 1986: 1) UF15737-027593. Two flowers with attached anthers. Note long pedicel. Scale bar equals 2 mm; 2) Enlargement of Figure 7.1 (indicated by upper arrow) to show anther. Scale bar equals 1 mm; 3) Enlargement of Figure 7.1 (indicated by left arrow) to show anthers and filaments. Scale bar equals 1 mm.