Picramnia hirsuta W.W.Thomas

  • Authority

    Thomas, Wm. Wayt. 1988. A Conspectus of Mexican and Central American Picramnia (Simaroubaceae). Brittonia. 40 (1): 89-105.

  • Family

    Picramniaceae

  • Scientific Name

    Picramnia hirsuta W.W.Thomas

  • Description

    Latin Diagnosis - Arbuscula (0.7) 2-7 m, P. matudai simulans sed plerumque hirsuta et foliola chartacea. Folia (9) 11-23-foliolata; rachis cum petiolo (13) 17-35 cm longa; foliolum terminale ellipticum, anguste ellipticum, obovatum, vel oblanceolatum, 7.5-15 x 2.3-6.4 (7.4) cm; foliola lateralia distalia elliptica vel anguste elliptica, 6-15 x 1.5-5.5 cm; racemus florifer 15-60 cm longus; corolla marronino- magentea.

    Species Description - Small tree or treelet, (0.7) 2-7 m tall, occasionally scandent, young stems densely hirsute, the hairs 1-3 mm long. Leaves imparipinnately compound, with (9) 11- 23 leaflets, those directly subtending inflorescence sometimes smaller and with fewer leaflets, all parts hirsute; rachis including petiole (13) 17-35 cm long, the petiole 1.5-7 cm long, 1-2.5 mm wide near basal leaflets; petiolules 1.5-5 mm long, 0.6-1.8 mm wide, hirsute, disarticulating easily when dried; leaflets char- taceous to membranous, adaxially sparsely hirsute and dark olive-green, abaxially hirsute and pale or sometimes slightly glaucous, the midrib and secondary veins usually +/- raised abaxially; terminal leaflet largest, elliptic to narrowly so or ob- ovate to oblanceolate, 7.5-15 x 2.3-6.4 (7.4) cm, the base cuneate or occasionally rounded, the apex acuminate to attenuate; lateral leaflets decreasing in size (par- ticularly in length) towards base of leaf, the base cuneate to rounded, symmetric to somewhat oblique, the apex acuminate to attenuate; distal lateral leaflets elliptic to narrowly so, 6-15 x 1.5-5.5 cm. Staminate inflorescence terminal to subter- minal, racemose, pendent, ca 20-60 cm long, 0.7-1 mm wide at start of flowering portion, hirsute, with ca 75-150 glomerules of flowers, flowers lacking or few on basal third; glomerules usually clustered, globose, ca 1 mm in diam, castaneous to brown, each subtended by a slender bristle-like bract 2-3 mm long; staminate flowers: pedicels ca 0.7 mm long; sepals 3 (4), ovate, 1.5-1.7 x 0.8-1.2 mm, acute, glabrous to sparsely hirsute medially, the apex acute to rounded; petals 3 (4), narrowly obovate, 2.3-2.6 x 0.5-0.6 mm, incurved or slightly cucullate, glabrous, maroon-magenta, the apex +/- rounded; stamens 3 (4), without inter- staminal nectaries, the filaments 2.7-3.2 mm long, the anthers bilobed, ca 0.5 x 0.4 mm; ovary vestigial, virtually absent. Pistillate inflorescence racemose, pen- dent, ca 15-60 cm long, 1-1.5 mm wide near basal flowers, hirsute, with ca 30- 100 flowers, each flower subtended by a bristle-like bract 0.5-1 mm long; pistillate flowers: pedicels 1-2 mm long; sepals 3-4, ovate, 0.9-1.1 x 0.6-0.8 mm, hirsute to sparsely so or rarely glabrous, apex acute to rounded; petals 3-4, elliptic to narrowly so, 1.5-1.6 x 0.4-0.6 mm, glabrous, maroon-magenta, the apex acute; staminodia 3-4, antepetalous, cylindric, 0.5-0.6 mm long; ovary urceolate, 1- 1.5 x 1-1.3 mm when stigmas receptive, pale hirsute; locules 2 (3); stigma branches 2, vitually sessile on apex of ovary, recurved, wine-red, each arm 0.6-1.3 mm long. Infructescence racemose, pendent, ca 20-75 cm long, 1.5-2 mm wide near basal flowers and somewhat narrower basally, hirsute, up to 30 fruits maturing; pedicels 4-7 mm long, hirsute, articulated at base; sepals 3-4, similar to pistillate sepals, divergent to reflexed; berries 2-locular, with 1-2 seeds developing, broadly ellipsoid to orbicular or broadly obovoid, mature berries 1-1.3 (1.7) x 0.6-1 cm, sparsely hirsute to glabrate, red to orange or salmon, becoming black when mature.

  • Discussion

    TYPE: MEXICO. Oaxaca: MPio. MATIAS ROMERO, lomas al S del Rio Verde, 11.5 km al S del Asseradero La Floresta (abandonado), +/- 24 km al S de Esmeralda, lomerio con suelos prof., selva de Terminalia, Dialium, Calophyllum, Sterculia mexicana, Pouteria neglecta, Pterocarpus, etc.; arbolito de 3 m, fruto rojizo, con came color mamey-anaranjada, 1701 'N, 94º48'W, 250 m, 18 Apr 1984, T. Wendt, G. Schatz & A. Montero 4443 (HOLOTYPE: CHAPA; ISOTYPE: NY).

    Additional specimens examined: GUATEMALA. Izabal: between Escobas and Montania Escobas, across bay from Puerto Barrios, 13 Apr 1940, J. Steyermark 39259 (F), along Rio Bonita, 21 Dec 1941, J. Steyermark 41717 (F); Quezaltenango: between Finca Pirreneos and Finca Soledad, lower S-facing slopes of Volcan Santa Maria, between Santa Maria de Jesus and Calahuache, 5 Jan 1940, J. Steyermark 33531 (F), same general area but along great barranco between Finca Pirreneos and San Juan Patzulin, 6 Jan 1940, J. Steyermark 33641 (F); San Marcos: above Finca El Porvenir, up Loma Bandera Shac on lower S-facing slope of Volcan Tajumulco, 9 Mar 1940, J. Steyermark 37337 (F, NY), 37322 (F), same general area but above Finca El Porvenir on "Todos Santos Chiquitos," 7 Mar 1940, J. Steyermark 37083 (F), Sierra Madre Mts about 8-10 km W of San Marcos, outer slopes of Tajumulco Volcano, 31 Dec-i Jan 1964/65, L. 0. Williams et al. 26923 (F). MEXICO. Chiapas: Mpio. BERRIOZABAL, 13 km NNW of Berriozabal on rd. to El Cairo and Finca El Suspiro, 900 m, 24 May 1985, W. W. Thomas & J. L. Villasefior 3629 (MEXU, NY), 2 Nov 1971, D. E. Breedlove & A. R. Smith 21676 (MICH, MO, NY), 1 Jan 1973, D. E. Breedlove 31240 (ENCB, MICH, MO); Oaxaca: MPIO. STA. MARiA CHIMALAPA, to La Floresta, 30 km S of rd. from Palomares to Uxpanapa, then SE of La Esmeralda on logging rd. to Rio Verde, in hills between Arroyo Humaca and Rio Verde, 300 m, W. W. Thomas et al. 3565 (CHAPA, NY); MPIO. MATiAS ROMERO, 6.2 km S on old rd. to Rio Azul which meets rd. from Boca del Monte to La Laguna 7.6 km W of La Esmeralda, 150 m, W. W. Thomas et al. 3581 (CHAPA, NY), 7.2 km al 0 de Esmeralda, en la terraceria La Laguna-Sarabia, luego 2.6 km al S por camino, 200 m, 9 Mar 1982, T. Wendt et al. 3636 (CHAPA, NY); Veracruz: MPIO. CATEMACO, Cumbre de Bastonal, 640 m, 15 Jan 1974, Refugio Cedillo Trigos y Fernando P. 18 (ENCB), Camino Bastonal a Santa Martha, 1000 m, A. G6mez-Pompa et al. 5390 (F), Rumbo al Poblado del Bastonal a 10 km del Poblado de Tebanca, 600 m, J. Ismael C. 1407 (ENCB), Chochovi, 500 m, F. Ventura A. 5868 (ENCB), 8 km (by air) NE of Catemaco, at highest point on road from Catemaco to Sontecomapan, 5 km N of junction with road around Laguna Catemaco, 500-550 m, M. Nee & J. L Caldaza 22534 (F); Mpio. HIDALGOTITLAN, Benito Juarez segundo, 100 m, G. Castillo C. 362 (F); MPIO. MINATITLAN, loma grande al S de Pob. 11, ?27 km al E de La Laguna, pendientes N del loma, cerca de la cafiada atras (al S) de las primeras lomitas, 320 m, 14 Apr 1984, T. Wendt et al. 4405 (CHAPA, NY), Zona de Uxpanapa, 13.7 km E of La Laguna, then 6.5 km N of dirt rd. to Belisario Dominguez, 130 m, 19 Apr 1985, W. W. Thomas et al. 3549 (NY); Faldas de Vilgia, 570 m, 23 Jan 1974, F. Ponce 63 (ENCB).

    Picramnia hirsuta appears to be restricted to rainforests near the Isthmus of Tehuantepec, Mexico, ranging from Catemaco, Veracruz, to the Uxpanapa region of Oaxaca and Veracruz with one collection from north-central Chiapas and several from adjacent Guatemala. This distribution corresponds in large part to a zone of high precipitation described by Wendt and Lott (1985) as ". . . extending from extreme southeastern Veracruz and adjacent Oaxaca through southern Tabasco to northern Chiapas, but not reaching Guatemala." The species normally occurs at elevations of 100 m to 1500 m in lowland or montane rain forests with one specimen from Guatemala collected at 2300 m elevation. With the exception of one specimen collected at 100 m, the Guatemalan collections are all montane from elevations of over 1300 m. At those elevations the rainfall may be com- parable to that found in the Uxpanapa region of Mexico. The rainfall or at least the mesic environment of the habitat may be more critical than the actual elevation at which the plants are found. In the Uxpanapa region, the plants occur on deep soils, possibly associated with limestone.

    This species can be distinguished by its hirsute indument and its large leaves with numerous, large, chartaceous leaflets. It is most similar to Picramnia matudai Lundell with which it shares the unusual character of maroon-magenta petals. While the Mexican collections are all quite hirsute, giving the species its name, the Guatemalan collections are less so. They are nevertheless strongly pubescent and have the large leaves and chartaceous leaflets characteristic of the species.