Grias peruviana Miers

  • Family

    Lecythidaceae (Magnoliophyta)

  • Scientific Name

    Grias peruviana Miers

  • Primary Citation

    Trans. Linn. Soc. London 30: 301. 1874

  • Common Names

    huevos de burro, huevos de toro

  • Description

    Author : Xavier Cornejo & Scott A. Mori

    Type: Peru. San Martín: prope Tarapoto, Río de Ventana, 1855-56 (fl, immature fr); R. Spruce 4541 (lectotype, K, designated by S. A. Mori in Prance & Mori, Fl. Neotrop. 21: 203 (1979); isolectotype, BM).

    Description: Pachycaul, understory to canopy, many branched trees, to 30 m x 50 cm, the trunk cylindrical, not buttressed. Bark smooth. Stems glabrous, the leaf-bearing ones 6-12 mm in diam. Leaves: petioles lacking to 115 x 2-8 mm, semicircular or subterete in cross section, glabrous; blades elliptic or oblanceolate, 20-120 X 8-35 cm, coriaceous, glabrous, often with inconspicuous reddish papillae or punctate abaxially, the base attenuate, cuneate or obtuse, the margins entire or serrulate, obscurely revolute, the apex acuminate; venation brochidodromous, the secondary veins in 11-50 pairs, the tertiary veins weakly percurrent, the higher order venation plane and difficult to see. Inflorescences cauline and ramiflorous, of 1 to several racemes arising from warty outgrowths, with 1 to 15 flowers, the rachises glabrous to densely pubescent, 5-115 mm long; pedicels 8-70 mm long, glabrous to densely pubescent, subtended by a single triangular to ovate bract, 1-3 x 2-4 mm. Flower buds ovate, mature flowers 3.5-7 cm diam.; hypanthium glabrous to densely pubescent; calyx completely enclosing bud, then usually apiculate, with circumscissle dehiscence and forming a rim 3-4 mm wide or splitting into 2-4 irregular lobes at anthesis; petals oblong or elliptic, rarely obovate, 17-30 x 10-25 mm, usually yellow, infrequently white, spreading and flat at anthesis; androecium obloid, the staminal tube 2-9 mm high, divided into 2 chambers, arching from base to apex abaxially, the lower chamber straight adaxially, the upper chamber slanting outward, with 93-171 stamens, the filaments constricted at apex, the outermost 6-15 mm long, the connectives absent, the anthers suborbicular, 0.6-1 mm long, with lateral dehiscence; ovary 4-locular, with 1-4 ovules per locule, glabrous and ± convexl at summit, the nectary disk absent, the style 0.5-1mm long or sometimes absent. Fruits elliptic, fusiform, or obovate, greenish-brown to brown, 7.5-13 x 5-7 cm, with 8 longitudinal ribs (dry), the mesocarp yellow to orange, 4-15 mm thick. Seeds 50-100 x 25-50 mm.

    Common names: Ecuador: Apái (Shuar), apay (Shuar), aguacate de monte (Spanish), aguacatillo (Spanish), guengawe (Huaorani), huevo de chivo (Spanish; Bonifaz & Cornejo, 2004), huevos de burro (Spanish: Cornejo 8422), huevos de toro (Spanish: Cornejo 8422), jagua de choque (Spanish/indigenous), jagüillo (indigenous), kuapiu (indigenous), llanero (Spanish), mango sacha (Quicha/Spanish), membrillo (Spanish), pacó (indigenous), pacora (indigenous), pure gugj (indigenous), sachamangua (indigenous), sapote de perro (Spanish), t soda (Colorado), vengaka (Huaorani), wa ga la puchi (Cayapa), ya ambo fino poca (Cayapa). Peru: apaí, apan (Aguaruna jivaro), mancoa (indigenous), nakunuk (Aguaruna jivaro), sacha mango, sacha mangua, sachamangua (Aguaruna).

    Distribution: West of the Andes in northwestern Ecuador and east of the Andes from Ecuador south to Cuzco Department in Peru. This species may also occur in the state of Amazonas, western Brazil. The disjunct distribution in Ecuador, with populations west and east of the Andes, may be the result of fruit dispersal by man (Prance & Mori, 1979).

    Ecology: Grias peruviana is usually an understory or less frequently a canopy tree in well drained soils of moist and wet forests. It is persistent in secondary habitats and sometimes left as a solitary tree in pastures.

    Phenology: Flowers and fruits have been collected throughout the year. However, it is most likely that there are different patterns of flowering and fruiting in different localities.

    Pollination: Jette Knudsen and Bertil Ståhl (pers. comm. to S. A. Mori, 2009) report that the Cerro Samama population of this species have flowers that emit a fruity scent and are often visited by small beetles, mainly of the Staphylinidae.

    Dispersal: Once fallen to the ground, the seeds are carried away by peccaries (Tajassu spp.), pacas (guantas in Spanish, Cuniculus paca), and agoutis (guatusas in Spanish, Dasyprocta spp.).

    Predation: Based on observations reported on labels, the fruits are eaten by squirrels (Sciurus granatensis) while still attached to the tree trunk (Cornejo & Bonifaz 4796) and, once fallen to the ground, they are preyed on by pacas (guantas in Spanish, Cuniculus paca) (Cornejo & Bonifaz 824, 7104). Chuck Peters (pers. comm., 2012) has also observed that squirrels srcatch the fruits as they are beginning to ripen tin order to determine if they are ready to eat. Then one day he observed that squirrels had consumed the pulp and the seeds were no longer present. Thus, it has been established that the fruit pulp is eaten by mammals, but it still has not been established if the seeds are preyed upon or if they are dispersed.

    Field characters: Grias peruviana is characterized by the relatively long, slender petioles; cauline inflorescences that are nearly fasciculate or in racemes up to 12 cm long; slender; long, slender pedicels; buds completely enclosed by the calyx; a calyx with either circumscissile dehiscence and leaving a calycine rim or splitting irregularly and leaving irregular calyx-lobes; and yellow petals and androecia.

    Taxonomic notes: Collections of Grias peruviana from the Huallaga river basin of Peru have larger more gradually tapered leaves than those from further north. As there is no morphological or geographical discontinuity between collections from the two regions this variation has been interpreted as clinal (Prance & Mori, 1979). The presence of this species both east and west of the Andes should be further investigated to determine if this species has been introduced from one side of the Andes to the other by humans.

    Conservation: This species has healthy populations which produce abundant and viable seeds, even in disturbed and open areas; therefore we regard it as a species of Least Concern (LC).

    Uses: The mesocarp of the fruit has been reported to be edible (Freire & Naranjo 403). The leaf blades are used to wrap and cook rats by the Awá Indians (Tipaz 1536). The wood is boiled in water and the resulting decoction is drunk to give strength (Kvist 40220, 40121) and used against fever (Freire & Naranjo 403). The decoction of bark is also used as a contraceptive, but large doses may cause sterility (Limbach 105). The seeds are used to treat dysentery (Jimpikit RBAE2000). The inner part of the seed is macerated, squeezed, and the extracted juice is used for rectal cleansing, and, according to Cornejo & Macas 8422, also for treating baldness. The seeds are are boiled and the decoction is used as a drink to eliminate parasites (Mendoza & Vega 93).

    Etymology: The epithet refers to Peru, the country where the type collection was gathered.

    Source: Mori in Prance, G.T. & S. A. Mori. 1979. Fl. Neotrop. 21, Lecythidaceae-Part I: 203-204.

    Acknowledgements: We are grateful to J. Sanz Biset, J. Clark, and B. Stahl for allowing us to use their images to illustrate the characters of this species.

  • Floras and Monographs

    Grias peruviana Miers: [Article] Prance, Ghillean T. & Mori, S. A. 1979. Lecythidaceae - Part I. The actinomorphic-flowered New World Lecythidaceae (Asteranthos, Gustavia, Grias, Allantoma & Cariniana). Fl. Neotrop. Monogr. 21: 1-270.

  • Narratives

    SEMs of pollen grains of Grias peruviana. Photos by X. Cornejo and J. Muller.