Iriartella stenocarpa Burret

Authority

Henderson, A. 1990. Arecaceae. Part I. Introduction and the Iriarteinae. Fl. Neotrop. Monogr. 53: 1-100. (Published by NYBG Press)

Family

Arecaceae

Scientific Name

Iriartella stenocarpa Burret

Type

Type. Peru. Loreto: Mouth of Río Napo nr. Río Amazonas, Mar 1931, Hopp 1110 (holotype, B).

Synonyms

Iriartea stenocarpa (Burret) J.F.Macbr., Iriartella ferreyrae H.E.Moore

Description

Species Description - Stems cespitose, rarely solitary, erect or leaning, forming loose to dense clusters of up to ten main stems, to 3 m tall, to 2 cm diam., red-brown to brown, upper part sparsely covered with short stiff trichomes, lower part glabrous and with lenticels, with nodes prominent and internodes 25 cm apart, stems developing from base of other stems or on the ends of long black rhizomes; stilt roots few, nearly vertical, closely spaced, sparsely spiny, often poorly developed and not apparent, branched at or below ground level, 20 cm x 3 mm. Leaves 3-5, pinnate, rarely entire, spreading; sheaths forming a loose crownshaft, 11.5-18 cm long, 1 cm diam., brownish, densely reddish-brown- or whitish-tomentose and sometimes with scattered to dense dark brown hairs to 2 mm long; petiole ridged, terete, 10-19 cm long, 4 mm diam., same tomentum as sheath but lacking long hairs; rachis ridged and densely brown-tomentose adaxially, rounded and densely white-tomentose abaxially, 18-50 cm long; pinnae 5-8 per side, entire, alternate, rhombic-cuneate to almost linear in outline, proximal margins entire for half their length, distal margins entire for one third their length, then both margins praemorse, glabrous adaxially and abaxially, or occasionally moderately to densely covered in simple hairs with swollen bases; proximal pinna 6-11 x 1-4 cm; middle pinna 14-33 x 2.5-10 cm; apical pinna deeply bifid, 3.3-18 x 14-24 cm; veins radiating from base, to four main ones per pinna, prominent abaxially. Inflorescence to 50 cm long in bud, erect and interfoliar in bud, becoming pendulous at anthesis, and infrafoliar in fruit; peduncle dorsiventrally compressed, to 45 cm long, densely brown-tomentose; prophyll inserted near base of peduncle, papyraceous, 4-11 cm long, ancipitous, densely brown-tomentose; peduncular bracts 2-3, inserted 1-7 cm apart, with same tomentum as prophyll; rachis 1-8 cm long, rachillae 3-20, simple, 4.5-20 cm long, adnate to rachis for 1-2 cm, sparsely brown-tomentose, especially near base, green, subtended by an acute bract; triads spirally arranged, 2-4 mm apart; flowers in triads, towards end of rachillae paired or solitary staminate, green at anthesis; staminate flowers 3-3.5 mm long; sepals widely ovate, 1 mm long, 1.7-2 mm wide, very briefly connate below, imbricate and free above, gibbous; petals ovate, 3.2-3.5 x 1 mm; stamens six; filaments very short and thick; anthers basifixed, orange; pistillode lacking; pollen with reticulate exine; pistillate flowers 1.5-1.7 mm long; sepals free or very briefly connate below, widely ovate, imbricate, 1 x 1.5 mm; petals widely ovate, imbricate 1 x 1.5 mm; staminodes six, small and dentiform, three opposite sepals, three opposite petals; ovary trilocular, triovulate, usually one ovule developing, glabrous, irregularly shaped; stigmas three, sessile, reflexed at anthesis; fruit ellipsoid, 0.9-1.5 x 0.5-0.7 cm, stigmatic scar basal; epicarp glabrous, orange at maturity and splitting irregularly; mesocarp 1 mm thick, white; seed ellipsoid, 10 x 7 mm; raphe branches anastomosing, hilum rounded, embryo apical; endosperm homogeneous, eophyll entire, becoming minutely bifid.

Discussion

When Burret (1931) described Iriartella steno-carpa, from Peruvian material collected at the mouth of the Río Napo, he did not see staminate flowers. Later, Moore (1963) placed I. stenocarpa in synonymy under I. setigera, and described I. ferreyrae from southern Peru. Moore distinguished his new species by its free staminate sepals, not realizing that all Peruvian material of Iriartella has this character. The correct name for Peruvian material is therefore I. stenocarpa. It is curious that Moore made such an oversight, since he himself collected material of Iriartella at staminate anthesis near Iquitos, and other collections with staminate flowers were available for study at that time. The type locality of I. stenocarpa is approximately 70 km from Iquitos. There are a few fruiting perianths on the type specimen, and on these the staminodes can clearly be seen. Although there are no more recent collections from the type locality, there is little doubt that the material collected by Hopp is the same species as that occurring near Iquitos.

Common Names

Camomila, casha ponita, Paxiúbinha do macaco

Distribution

Amazonian Peru and adjacent Brazil (Acre) and Colombia (Amazonas), in lowland forest below 500 m (Fig. 27).

Colombia South America| Amazonas Colombia South America| Peru South America| Loreto Peru South America| Pasco Peru South America| Ucayali Peru South America| Brazil South America| Acre Brazil South America|