Carpolithes sp. 2

Tiffney, Bruce H. & Manchester, Steven R., 2022, The Early Middle Eocene Wagon Bed Carpoflora Of Central Wyoming, U. S. A., Fossil Imprint 78 (1), pp. 51-79 : 67

Carpolithes sp. 2

Text-fig. 8f–j

M a t e r i a l. One specimen, chalcedony cast, USNM

PAL 772367.

D e s c r i p t i o n. Disseminule narrowly ovate to ovate in lateral view, nearly circular in cross section, 9.6 mm in length, 5.6 by 5.7 mm in cross section. The broad basal end has a central point of attachment, lateral to which on one side is a distinct structure consisting of two parallel smooth lineations flanking a wider, raised, central zone of elongate cells ( Text-fig. 8f ). This extends approximately 40 % of the length of the structure before being obliterated by erosion of the surface. A very faint single line occurs on the opposing margin of the structure, extending about 50 % of the length of the structure before similarly being eradicated by erosion of the surface of the object.

D i s c u s s i o n. The basal scar and particularly the well-developed lineation on one side suggest that this could be interpreted as a seed with a lateral vascular strand or raphe. However, the apical end of the seed is badly eroded so that the full path of the raphe-like structure cannot be traced. There is a similarity in form and size to the seeds of Nuphar SM. ( Nymphaeaceae SALISB. ), but details of the cellular structure and operculum are not available to confirm its identity.

Figures

Text-fig. 8. Carpolithes (a–t). a–e: Carpolithes sp. 1. USNM PAL 772366. Scale bar = 1cm. a: Lateral view of endocarp, note two longitudinal ridges. b: Lateral view of endocarp rotated 90° from (a), note singlelateral ridge in center, a, b reflected light, palladium coated. c: Lateral view, Micro-CT scan surface rendering. d: View of rounded end of the endocarp, reflected light, palladium coated. e: View of the opposite (pointed) end of the endocarp, note split; reflected light, palladium coated. f–j: Carpolithes sp. 2. USNM PAL 772367. Scale bar = 5mm. f: Lateral view, base down; note raphe-like structure (arrow), reflected light, palladium coated. g: Lateral view, the raphe-like structure extending vertically from the base. h: Lateral view, rotated 90° from (g). i: Lateral view, the opposite face to that in (h). j: Basal view, raphe-like structure running from the center to the right of the image. g–j: CT scan surface renderings. k–o: Carpolithes sp. 3 USNM PAL 772368. Scale bar = 5mm. k: Ventral view of the specimen, note flared apical extension, reflected light, uncoated. l: Dorsal view illustrating the flared apical extension, rotated 180o from (k). m: Lateral view rotated 90° from that in (l). n: Apical view, the apical extension with central pore (arrow) and a clear lineation running down the side to the top of the image. o: Basal view. l–o: Micro-CT scan surface renderings. p–t: Carpolithes sp. 4. USNM PAL 772369. Scale bar = 3mm. p: Basal view illustrating the concentric rings of radiating possible cells surrounding a central depression. q: Lateral view, base down, note possible cellular pattern. r: Lateral view, rotated 180° from (q), base down; p–r: reflected light, palladium coated. s, t: Basal and lateral views, micro-CT scan surface renderings.