Maclura

• Authority

  Berg, Cornelius C. 2001. Moreae, Artocarpeae, and (Moraceae): With introductions to the family and and with additions and corrections to Flora Neotropica Monograph 7. Fl. Neotrop. Monogr. 83: 1-346. (Published by NYBG Press)

• Family

  Moraceae

• Scientific Name

  Maclura Nutt.

• Type

  Lectotype, Kaastra, Acta Bot. Neerl. 21: 661. 1972. Sloane, Hist. Jamaica 2: t. 158

• Synonyms

  Morus tinctoria L., Broussonetia tinctoria (L.) Kunth, Fusticus tinctoria Raf., Chlorophora tinctoria (L.) Gaudich. ex Benth.

• Description

  Genus Description - Tree, to 30 m tall, or shrub, especially if juvenile armed with axillary, solitary, or sometimes paired thorns to 3.5 cm long, straight and slender, bearing minute scale-leaves at the base. Leafy twigs 0.5-4 mm thick, sparsely to densely puberulous to hirtellous or almost glabrous. Lamina elliptic to oblong, sometimes to subcordiform to suborbicular or to lanceolate, 1.5-15(-20) × 0.8-7(-8.5) cm, broadest at or below the middle, often distinctly inequilateral, chartaceous; apex acuminate or (sub)acute; base obtuse truncate to cordate (or to subacute); margin subentire to coarsely crenate- to serrate-dentate, or if juvenile, then sometimes lobate to lacerate; upper surface hirtellous to puberulous on the whole surface or only on the lower part of the midrib; lower surface (very) sparsely to densely puberulous, hirtellous, or tomentose on the veins; venation plane above, prominent or the smaller veins plane beneath; lateral veins 5-10(-17) pairs; tertiary venation reticulate; petiole 0.2-1.5(-2) cm long, sparsely to densely puberulous to hirtellous or subglabrous; stipules fused, ovate to triangular, 0.2-1 cm long, white-puberulous to subsericeous, caducous. Staminate inflorescences: peduncle 0.2-2 cm long, densely puberulous to tomentellous; spike 2-13 cm long, 0.2-0.4 cm diam., ± interrupted and with an abaxial sterile strip; flowers crowded; tepals (3-)4, almost free, ca. 1 mm long, densely puberulous; stamens (3-)4; filaments ca. 2 mm long; anthers ca. 0.6-0.8 × 0.6-0.8 mm; pistillode flat, ca. 1 mm long, apiculate; bracts elliptic, with 2 embedded yellow dye-containing "glands." Pistillate inflorescences in the leaf axils; peduncle 0.1-1 (-2) cm long, puberulous to short-velutinous; head (subglobose, 0.3-0.6 cm diam.; tepals almost free, 1-1.5 mm long, ± cucullate and conduplicate, normally with 2 embedded yellow dye-containing "glands," the upper parts densely puberulous, sometimes partly with uncinate hairs; ovary ca. 1 mm long; stigma 1, 3-10(-18) mm long, sometimes the second stigma developed, to 3 mm long; bracts 1-2 mm long, cucullate to subpeltate, ± swollen due to 2 embedded yellow dye-containing "glands," the upper part puberulous. Infructescences globose to ellipsoid, ca. 1-1.5 cm diam.; fruiting perianth ca. 3 mm long; fruit lens-shaped, ca. 3.5 mm long; cotyledons plane, not enveloping the slightly curved radicle; bracts usually strongly swollen, to 3.5 mm long.

• Discussion

  The number of infraspecific names created, as by Bureau (1873), already indicates that the species is very variable. It is particularly so in the shape and size of the lamina, the indumentum, and the presence and length of the thorns. The variation is to a large extent related to the stage of development; juvenile and adult stages show condiderable differences. Juvenile specimens often have lobate laminas (pinnately lobate or in particular in subsp. mora trilobate, sometimes to laciniate in subsp. tinctoria) and numerous long thorns. In adult specimens the lamina is normally entire and the thorns short and often few. Juvenile features may be retained. In the reproductive parts of the plant, variation is conspicuous in the length of the staminate inflorescences, the diameter of pistillate inflorescences, and in the length of the style. The characteristic yellow dye-containing "glands" are not consistently present in the bracts and tepals of the pistillate flowers. They occasionally occur in the tepals of staminate flowers.

  The pattern in the variation only justifies recognition of two infraspecific entities at the subspecies level. The two subspecies are largely allopatric, showing marginal overlap of their ranges of distribution.