Panopsis pearcei Rusby

  • Authority

    Prance, Ghillean T., et al. 2007. Proteaceae. Fl. Neotrop. Monogr. 100: 1-218. (Published by NYBG Press)

  • Family

    Proteaceae

  • Scientific Name

    Panopsis pearcei Rusby

  • Type

    Type. Bolivia. Tipuana-Guanai, 1200-1500 m, Dec 1892 (fl), Bang 2237 (lectotype, designated here, NY; isolectotypes, BM, E, F [2 sheets], G, GH, K, MICH, MO, NY).

  • Description

    Species Description - Tree. Twig indumentum densely tomentose to pilose, the hairs somewhat appressed, light brown to ferruginous, glabrescent; bark brown, at times suffused red or dark gray; lenticels absent or present and few to many, small, enlarging to 1 mm long, circular to elliptic, plane becoming raised peripherally, granular, gray through orange-brown to rufous. Axillary buds small, usually solitary (rarely two or three stacked), ferruginous- to rufous-villous. Leaves subcoriaceous, decussate or subopposite-decussate, spiral or occasionally in verticils of four, indumentum dense, sericeous above, less dense and shorter beneath, becoming close-appressed short-pilose, glabrescent; the hairs pale yellow to ferruginous. Petioles 0.7-2 cm × 1-2 mm (3 mm at base), flat to semiterete, the indumentum closely appressed, densely-sericeous, to sparsely short-pilose, longer and denser above, few long hairs interspersed occasionally, golden to ferruginous to gray. Lamina 3.5-16 × 1.5-5.7 cm, elliptic, narrowly elliptic, oblong or oblanceolate; base symmetrical, less commonly eccentric, cuneate, sometimes slightly decurrent, rarely obtuse; apex acute to obtuse sometimes minutely mucronate; margin thinly revolute; venation conspicuous to obscure, slightly raised above, brochidodromous, forming two or three marginal veins (as one merges with leaf margin, another becomes predominant); midrib plane to raised at base becoming slightly grooved beyond base; lateral veins 7-9(-11 rarely) pairs, leaving midrib at 40-50(-60)°, arcing immediately. Primary axis of inflorescence unbranched or branched, 4.5-13.5 cm × 1-1.5 mm; (1-)3-8(-12) lateral inflorescences at 1-7 nodes, 2.5-10 cm × 0.5-1 mm, verticillately or spirally arranged, well spaced, accessory branching common; indumentum ferruginous- to rufous-tomentose. Common bracts 0.5-0.8(-1.5) mm long, ferruginous- to rufous-tomentose. Pedicels 1.5-4.8(-6.0) × 0.2-0.7 mm, indumentum short-tomentose, not closely appressed, ferruginous-rufous. Flowers 3-5 mm long, the perianth indumentum short-sericeous, closely appressed, ferruginous to rufous; free part of filaments 2-3 mm long, adnate 0.3-0.6 mm from base of perianth parts; anthers 0.6-1 × 0.3-0.5 mm, oblong to elliptic; hypogynous nectary 0.5 mm long, shallow-lobed; ovary hairs reaching 1-1.5 mm from base, occasionally few hairs continue up style, orange-red to red-brown; style 0.30.4 mm wide at midlength, not clavate to clavate. Fruit pedicel 3-4 × 2 mm. Fruit 2.1-2.5 cm long, 1.9-2.8 cm wide, subglobose, the apical scar slightly to markedly offset from line of fruit axis, surface smooth, the indumentum short, closely appressed, bright brown sericeous, glabrescent; pericarp 2 mm thick; outer mesocarp very thin, granular, orange-brown; mid mesocarp 1.5-1.8 mm thick, pale brown, mucilage/resin strands present (dried, hardened dark red-brown resin marking positions); inner mesocarp very thin, black. Seed coat thin, chartaceous, dark brown. Seed fleshy, subglobose, 1.8 cm long, 2.3 cm wide. Field characters. Tree or shrub, 5-15 m tall, with gray bark. Flowers yellowish-white or white, fragrant; anthers white; ovary hirsute. Fruit described as being a large, hard nut, or a drupe with one or two unwinged seeds.

  • Discussion

    One of the three specimens of Bang 2237 of Panopsis pearcei at NY has been chosen as the lectotype in preference to duplicates kept at other herbaria, because this specimen was most likely to have been that used by Rusby in writing the protologue.

    Panopsis pearcei Meisner ex Rusby has been resurrected from P. rubescens var. sprucei and separated from P. rubescens (Pohl) Rusby altogether. The two species are remarkably close vegetatively, except that the petioles are generally slightly longer, the angle at which the lateral veins leave the midrib is usually more acute, with the veins arcing immediately on leaving the midrib, and the marginal vein consists of series of loops instead of one continuous loop. The inflorescence structure shows equal variability in P pearcei as in P. rubescens, but the indumentum of P. pearcei is generally redder. Pedicels of P pearcei are usually shorter and support shorter flowers; and the shallow-lobed hypogynous nectary is at the lowest end of the size range for P. rubescens, while the stamens are adnate nearer to the base of the perianth parts.

    Panopsis sprucei Meisner ex Rusby was based on the collection Spruce 1817, as it is, according to Rusby’s protologue, “the same as Spruce’s no. 1817 and very near P. rubescens Pohl.” The other specimen that Rusby mentions, Bang 1686, was collected in 1892 and so was not available to Meisner, who died in 1874. Meisner published the name Andriapetalum sprucei in 1856, basing his description on Spruce 1817, which makes Rusby’s name illegitimate. Thus, the reference to Meisner as manuscript author of P sprucei is incorrect, as Rusby was in fact making a new combination. The name P. sprucei Meisner ex Rusby must become a synonym of the name P. rubescens (Pohl) Rusby, and a new name found for the species in question. Rusby described another new species in 1907, P. pearcei, which we believe to be the same as the Bang (1656) collection mentioned in the description of P. sprucei, and presumably what Rusby based his description on. Therefore, P. pearcei is the name adopted here, the type being Bang 2237.

    The mature fruiting specimen of Panopsis pearcei (Dorr et al 6708) is glabrous, indehiscent, subglobose, and very different from the flattened, commonly elliptic, dehiscent form of the mature P. rubescens fruit in which the indumentum is maintained. For such fundamental differences in fruit structure, it is remarkable that the species should be so similar vegetatively.

    A specimen collected in the Sierra de la Macarena of Meta, Colombia (Philipson et al. 1883) is considered to be most closely related to Panopsis pearcei. The floral morphology is comparable but for its less intense orange-brown tomentum on all parts of the inflorescence. Vegetative morphology differs to a greater extent: the petioles are longer, the lamina base narrowly attenuate and markedly revolute, venation of the underside of the leaf inconspicuous and barely raised, and the reticulation more intricate. These differences are not great enough to justify making a new species of it, and obviously fruiting material is of utmost importance. The plant lies within the altitudinal range of P. pearcei but is outside the present geographical range, which extends as far north as southern Ecuador. More material will better define the status of this specimen.

    The two specimens from Ecuador and Peru have broader leaves than the Bolivian group, but for the moment, there is insufficient information to split P. pearcei further.

    Phenology. Flowering in Jan, Apr, Aug, Oct, and Dec; fruiting in Dec (mature fruits) and Jan (imm. fruits).

  • Distribution

    Found in Bolivia, Peru, and Ecuador at 800-2780 m alt. At one locality, said to be growing in high montane forest with Podocarpus disturbed by logging; at another, in jalca vegetation with grasses.

    La Paz Bolivia South America| Loja Ecuador South America| Zamora-Chinchipe Ecuador South America| Cajamarca Peru South America| Yungas Bolivia South America|