Dicotylophyllum silberlingii, Wolfe & Tanai, 1987

Manchester, Steven R., 2014, Revisions To Roland Brown’S North American Paleocene Flora, Acta Musei Nationalis Pragae Series B 70 (3 - 4), pp. 153-210 : 177-178

Dicotylophyllum silberlingii

(R. W. BROWN) J. WOLFE et TANAI

Acer silberlingii R. W. BROWN (1962, p. 76 . pl. 46, fig. 7) was transferred to Dicotylophyllum silberlingii by Wolfe and Tanai (1987). According to those authors, “ The single specimen of “ Acer” silberlingii has intercostal venation comprised of many admedially oriented tertiary veins, some camptodromous secondary veins, narrowly arcuate dental sinuses, and veins that enter teeth have strong lateral bracing veins. The specimen is clearly not Acer , but we are unable to suggest a valid familial assignment.” ( Wolfe and Tanai 1987, p. 211 –212). From another upper Paleocene locality, however, Scott Wing (pers. comm., 2014), has observed this leaf species in close association with schizocarpic fruits that do indeed represent Acer —leading to the suggestion that the possible affinity of these leaves to Acer needs to be reconsidered.

Porosia verrucosa (LESQUERUEX) HICKEY emend. MANCHESTER et KODRUL

1878 Carpites verrucosus LESQUEREUX p. 305, Pl. 10, fig. 9 (basionym)

1962 Hydromystria expansa (HEER) HANTKE in Brown 1962 (part); p. 52, Pl. 16, figs 1, 3, 10, only

1977 Porosia verrucosa (LESQUEREUX) HICKEY 1977, p. 114 , pl. 54, figs 1, 3, 4 (not 2).

2014 Porosia verrucosa (LESQUEREUX) HICKEY emend MANCHESTER et KODRUL 2014 p. 82–83, Pl. 1–5.

Porosia verrucosa is a distinctive fruit type that existed from the Campanian to the Eocene; it was particularly common in the Paleocene of western North America and Far Eastern Russia ( Hickey 1977; Manchester and Kodrul 2014). The fruits were borne in schizocarpic pairs on stout pedicels with hypgynous perianth scar and bore numerous prominent circular cavities within the wall of each endocarp. The affinities are still uncertain although general similarities with Rutaceae have been noted ( Manchester and Kodrul 2014). Brown (1962) included these remains, along with leaves now treated separately as Limnobiophyllum , in his concept of Hydromystria expansa (HEER) HANTKE. Although considered at that time to be float leaves of an aquatic plant, the internal structure revealed in permineralized specimens, confirms that Porosia were unilocular, single-seeded fruits ( Manchester and Kodrul 2014).