Juglandicarya simplicarpa, Manchester, 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 : 172-173

Juglandicarya simplicarpa MANCHESTER

1987 Juglandicarya simplicarpa MANCHESTER p. 14, fig. 4.

Juglandicarya simplicarpa MANCHESTER fruits are known from several localities in the Rocky Mountains region. These are molds and casts of a relatively large, wingless nut 14 to 20 mm in equatorial diameter. The locule casts show typical juglandaceous morphology, but have only a primary septum without a secondary septum or other intrusions. These casts and molds resemble the permineralized fruit of Juglandicarya cantia REID et CHANDLER from the London Clay flora, but the internal anatomy of that fruit type has not been documented to show whether it is more closely related to Carya or to Juglans . Based on the common co-occurrence with Caryapollenites pollen ( Nichols and Ott 1978), and apparent absence of Juglans like pollen, we infer that these fruits may have belonged to the Hicorieae tribe of Juglandaceae ( Manchester 1987).

“ Carya ” antiquorum NEWBERRY

Newberry’s hickory, “ Carya ” antiquorum NEWBERRY (1898) , was based on leaflets recovered from a site at the mouth of the Yellowstone River. The original type specimens are accepted as representing Juglandaceae , but most of those included in the species by Brown (1962) and those described by Hickey (1977) have been shown to represent Aesculus hickeyi MANCHESTER, with palmately, rather than pinnately, compound foliage ( Manchester 2001). The syntypes of “ C. ” antiquorum , isolated leaflets originally depicted with drawings, were illustrated photographically by Manchester (2001, fig. 5A, B, E) for contrast with leaflets of Aesculus . Another specimen from a site near the type locality, with rachis bearing paired scars of detached lateral leaflets, indicates that this species was imparapinnate ( Manchester 2001, fig. 5C, D). The more precise affinities of Newberry’s “ C. ” antiquorum have not been determined. The leaflets lack gland impressions thus distinguishing them from Cyclocarya hispida , but this could be a preservational difference from site to site. There is a good possibility that “ Carya ” antiquorum coincides with the plant that produced Juglandicarya simplicarpa fruits.

The generic and familial assignments of “ Juglans ” berryana (KNOWLTON) R. W. BROWN and “ Juglans ” taurina R. W. BROWN and are questionable. The first of these was initially described by Knowlton (1924), as Dryophyllum berryana KNOWLTON and as Magnolia angustifolia NEWBERRY (based on counterpart impressions of the same leaf specimen). “ J. ” taurina has asymmetrical broad-ovate, entire-margined laminae with well-impressed transverse tertiary veins and appear to represent leaflets, but in the absence of additional diagnostic characters, it is not possible to rule out affinities with numerous other families having compound leaves.

? Rosaceae

Brown (1962) recognized four species of Prunus , i.e., P. coloradensis KNOWLTON , P. careyhurstia R. W. BROWN , P. maclearnii BERRY , and P. perita R. W. BROWN , and one species of fruit, Prunus corrugis R. W. BROWN. As stated by Wolfe (1977) “ Brown (1962) has attributed some leaves from the Rocky Mountain Paleocene to Prunus , but none of these leaves has the acropetiolar glands or glandular teeth characteristic of Prunus . ” There are many extant species of Prunus that do not display the acropetiolar glands, but without that character, it is difficult to distinguish this genus from others in the Rosaceae and other families, which leaves these identifications in some question. The fruits called Prunus corrugis R. W. BROWN were subsequently shown to represent Icacinaceae and were transferred to Icacinicaryites corruga by Pigg et al. (2008). A new fossil genus, Prunites , was established based on one of Brown’s species, resulting in the new combination, Prunities maclearnii (BERRY) MCIVER et BASINGER. McIver and Basinger (1993) agreed that it is close to extant Prunus , but noted the details of fine venation and fruits are not known.

Ulmaceae

Ulmus- like leaves were assigned by Brown (1962) to three different genera and species: Planera microphylla NEWBERRY , Ulmus rhamnifolia WARD and Zelkova planeroides (WARD) R. W. BROWN. The familial assignment is believed to be correct because of the distinctive combination of characters including asymmetrical lamina, short thick petioles, blunt, simple to doubly compound, non-glandular teeth, and percurrent tertiary venation. It is puzzling, however, that no fruits of Ulmaceae have been identified in association with these leaves at any of the Paleocene sites in North America or Asia ( Manchester 1989, and subsequent observations). The fruits that Brown attributed to Ulmus rhamnifolia were subsequently shown to represent Polygonaceae and later identified as Polygonocarpum curtisii MANCHESTER et O’LEARY ( Brown 1962, pl. 24, fig. 17) and Podopterus antiqua MANCHESTER et O’LEARY ( Brown 1962, pl. 24, fig. 18).