Joffrea

Name

Joffrea

Rank

Genus

Authors (Pub.)

Crane P. R. Stockey R. A.  

Publication

Growth and reproductive biology of Joffrea speirsii gen. et sp. nov., a Cercidiphyllum-like plant from the Late Paleocene of Alberta, Canada [1985/4]

Journal

Canadian Journal of Botany

Volume

63

Issue

2

Page number

341

Year

1985

Parent Taxon

[Family] Cercidiphyllaceae

Fossil Status

shoots (with infructescences)

Type

Joffrea speirsii

Diagnosis

Vegetative axes with long and short shoots. Short shoots alternate or subopposite with diamond-shaped leaf scars 2-5 mm high, 5-6 mm wide, each with a central, circular, vascular bundle scar. Short shoot leaves opposite and decussate. Leaves petiolate; petiole long with expanded base. Lamina simple, elliptic, ovate or obovate, length to width ratio 1 :0.75- 1.25. Apex obtuse to rounded; base rounded, truncate or cordate, with lamina often shortly decurrent down the petiole. Margin crenate; crenations generally most prominent in upper two-thirds of leaf. Major venation actinodromous, midrib flanked by one or two pairs of lateral primary veins. Inner primary veins always prominent, extending into upper half of lamina. Outer primary veins always weakly developed, usually confined to basal third of leaf. First strong secondary veins branching from niidrib at about midpoint of leaf. Inner primary veins producing strong secondary veins towards margin. Secondary veins from niidrib and outer secondary veins from inner primaries forming angular brochidodromous loops; loops of higher order veins produced closer to margin. Areoles well developed, polygonal, with branched freely ending veinlets. Margin with glands at tips of crenations; glands projecting slightly from margin but predominantly set within lamina of leaf; each gland supplied by a median vein from brochidodromous loops near margin and two lateral weakly developed veins that run parallel with apical and basal margins of the crenation and converge toward base of gland. Pistillate inflorescences unisexual; no indication of stamens or perianth. Inflorescences produced from axillary buds at apex of short shoots, surrounded at base by bud scales, each bearing approximately 40 carpels spaced every 1-5 nim on short side branches around a central axis. Side branches 1.5-3 mm long bearing one or two carpels; each carpel or pair of carpels, borne on a short stalk 1-2 mm long. Junction between carpel stalk and side branch of main inflorescence axis marked by a distinct joint. Carpels narrowly ellipsoidal, occasionally narrowly obovoid; ventral surface straight to slightly convex, dorsal surface convex, straight, or slightly concave. Ventral surface with a single longitudinal suture. Apex with an abaxially coiled or recurved style. Body of carpel, excluding stalk and style, 9- 1 I mm long, 3-4 mm wide. Each carpel with three main vascular strands, one on either side of the ventral suture, the other medial and dorsal. Ventral and dorsal strands connected by a weakly developed system of anastomosing lateral vascular strands. Ovules anatropous. Main axis of mature infructescences 2-3.5 mm thick, follicles more widely spaced (every 6- 1 1 mm) than carpels of pistillate inflorescences. Body of mature follicles 18-30 mm long, 5- 10 mm wide. Follicle wall thick, consisting of an outer layer with longitudinal fibrous ribs and an inner layer of closely spaced transverse fibers. Follicles producing numerous flattened, winged seeds, 3.5-8.0 mm long and 1.5-3.5 mm wide. Seeds crescent shaped, one edge convex, the other straight or concave. Seed surface finely striated; with seed body positioned close to convex margin at proximal end of wing; body elliptical, 2-3.5 mm long, 0.5- 1 mm wide, occasionally obovate, and pointed at micropylar end. Raphe arising close to seed body but following straight or concave margin into wing; turning abruptly before entering chalaza of seed body. Germination epigeal, producing a pair of broadly ovate to oblong cotyledons. Cotyledons with a rounded apex, 2.0-4.0 mm long, 1.5-3.0 mm wide; venation pinnate and camptodromous. Seedling leaves ovate, apex acute to rounded; base obtuse, margin sparsely crenate with glandular teeth.