Callistemonites indicus Bande, R.C.Mehrotra et U.Prakash

Plant Fossil Names Registry Number: PFN001608

Act LSID: urn:lsid:plantfossilnames.org:act:1608

Authors: M. B. Bande, R. C. Mehrotra & U. Prakash

Rank: species

Genus: Callistemonites Bande, R.C.Mehrotra et U.Prakash

Reference: Bande, M. B., Mehrotra, R. C. & Prakash, U. (1986): Occurrence of Australian element in the Deccan Intertrappean flora of India. – The Palaeobotanist 35(1): 1–12., link

Page of description: 9

Illustrations or figures: figs 20-22

Name is type for

Types

Original diagnosis/description

Incomplete spike-like infructescence, 4–12 cm in length and 1–2 cn in diameter, made up of 6–34, small fruits. Fruits spirally arranged, ovoid in shape measuring 8/4 mm in size and enclosed by persistent, cup-shaped perianth. Each fruit has a circular to truncate opening at the apex measuring 2–3 mm in diameter.

Emended diagnosis

Emended by Manchester, Kapgate and Smith in Smith et al. (2021: Int. J. Pl. Sci. 182(2): 102):
Fruits elongate, 9.0 cm long, and ca. 1.5 cm in diameter. Seeds arranged in longitudinal rows mostly oriented with their hilar scars protruding toward the central axis of the fruit (fig. 8A–8C), from which we infer axile placentation, with ca. 12 seeds per vertical row. Seeds ellipsoidal, 4–6 mm in diameter, 6–7 mm long, smooth (fig. 8D), elliptical to subcircular in transverse view (fig. 8A–8C), truncate at the hilar end with a prominent hilar rim, tapered and rounded at the chalazal end (fig. 8D). The hilum is operculate, 2–3mmin diameter, situated centrally (fig. 8D, 8E). The seed coat is moderately thick, 0.25 mm (fig. 8F). Most of the seeds are exposed with false external surfaces, that is, as smooth, rounded internal molds of the embryo cavity, with the surrounding seed coat fractured away except where still embedded in the underlying chert (fig. 8C, 8F). However, a few of the permineralized seeds have retained the seed coat over the surface (fig. 8D, upper and lower left). The conical protrusion seen at the apex of the embryo cavity molds (e.g., fig. 8C, 8E) contrasts with the flattened or truncate surfaces in the corresponding locations of seeds with intact seed coats (fig. 8D, upper left and central). That conical protrusion is interpreted as the infilling of the base of the operculum and its apical tip as the micropylar position. A circular crest that surrounds the hilum is interpreted as a hilar rim (fig. 8C–8E). Internal structure of the seeds is not well preserved, but longitudinally fractured examples (fig. 8D, central and right) show that the chalazal end was tapered and rounded.

Etymology

The species has been named as Callistemonites indicus indicating its occurrence in the Indian strata.

Stratigraphy

Paleogene
Deccan Intertrappean beds, early Tertiary

Locality

India
Ghughua (23° 7' N 80° 37' E) near Shahpura, Madhya Pradesh