Bactris ptariana Steyerm., Fieldiana, Bot. 28: 77 (1951)

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Distribution

Map uses TDWG level 3 distributions (https://github.com/tdwg/wgsrpd)
Guyana present (World Checklist of Arecaceae)B
Venezuela present (World Checklist of Arecaceae)B
Venezuela (Bolívar) and Guyana; (Henderson, A.J., Bactris (Palmae) in Flora Neotropica Monographs 79. 2000)A

Habitat

  • In open areas near forest margins or in forest, or dwarf forest, usually on white sandsoils (wallaba forest in Guyana), at 10-1980 m elevation. (Henderson, A.J., Bactris (Palmae) in Flora Neotropica Monographs 79. 2000)A

Discussion

  • Bactris ptariana is diagnosed by its clustered, black, pilose leaf spines, rachillae densely covered with short, brown or white, flexuous trichomes, and obovoid fruis. It is so similar to Bactris balanophora, especially in its clustered, pilose leaf spines, rachillae densely covered with trichomes, and fruit with adherent endocarp fibers, that it is hard to imagine they are not related, or even conspecific (although placed indifferent clades by Sanders, 1991). Specimens from higher elevations (1000-2000 m) in Bolívar, Venezuela differ from the lowland specimens from Guyana in their plicate, linear pinnae that are densely spinulose abaxially, and their larger inflorescences. As far as can be judged from the specimens available, this variation is continuous with elevation. (Henderson, A.J., Bactris (Palmae) in Flora Neotropica Monographs 79. 2000)A

Common Name

  • Guyana: maswa. (Henderson, A.J., Bactris (Palmae) in Flora Neotropica Monographs 79. 2000)A

Description

  • Stems solitary or cespitose, 2-3(-9) m tall, 3-5(-10) cm diam., spiny on internodes.
    Leaves 5-9; leafspines distinctly clustered, black, somewhat flattened, pilose except at base, spinulose, 1-3 cm long, dense on sheath and on lateral surfaces of petiole, fewer on rachis; sheath 20-76 cm long; ocrea not seen; petiole 15-40(-80) cm long; rachis 1-2 m long; pinnae 15-47 per side, irregularly arranged in clusters but spreading in more or less the same plane, linear or linear lanceolate, acuminate, sometimes strongly plicate, sparsely to densely spinulose abaxially; middle pinnae 44-65 x 2.5- 5 cm (the apical pinna wider than the others).
    Inflorescences infrafoliar, borne among the persistent leaf bases; peduncle 11-24 cm long, recurved, spiny; prophyll 7-12 cm long; peduncular bract 12-48 cm long, sparsely to densely covered with appressed, black spines to 1 cm long; rachis 2-5 cm long; rachillae 12-25, 6-17 cm long, at anthesis densely covered with short, brown or white, flexuous trichomes; triads irregularly aranged almost to apex of rachillae among paired or solitary staminate flowers; staminate flowers 3-4 mm long; sepal lobes ca. 1 mm long; petals 3-4 mm long; stamens 6; pistillode absent; pistillate flowers 3-3.5 mm long; calyx annular,0.5 mm long, glabrous or pilose; corolla cupular, 2-2.5 mm long, densely spinulose; staminodes absent; fruits 0.7-1 x 0.6- 0.8 cm, obovoid, rostrate, bright orange or red, rarely minutely spinulose; mesocarp starchy; endocarp turbinate, the sterile pores slightly displaced longitudinally; endocarp fibers absent or present and adherent to endocarp; fruiting perianth with obscure calyx and lobed, tomentose corolla, without staminodial ring. (Henderson, A.J., Bactris (Palmae) in Flora Neotropica Monographs 79. 2000)A

Materials Examined

  • VENEZUELA. BOLÍVAR: El Dorado, Santa Elena, Río Cauí, 1200-1400 m, 10 Mar 1975, Bogner 1061 (BH); Río Tehuanen, between Kavanayén and Ptari-tepuí, 1240 m, 13 Aug 1970, Moore et al. 9699 (BH); Cerro Venamo, 1395-1400 m, 14 Apr 1960, Steyermark & Nilsson 161 (NY), 31 Dec 1963, Steyermark et al. 92478 (BH). Steyermark et al. 92778 (NY); Carraotepuí, 1675-1980 m. 5-6 Dec 1944, Steyermark 60869 (NY); Meseta del Jaua, 4°41'N, 64°13'W, 11-12 Feb 1974, Steyermark et al. 108925 (BH, K).
    GUYANA. Mabura region, Pibiri, 5°1'N, 58°37'W, 6 Apr 1993, Ek et al. 801 (NY), 21 Jul 1993, Ek et al. 860 (NY); Potaro rd., 21 Apr 1952, Forest Department 3349 (NY); Potaro-Siparuni region, Kaietur Falls National Park, 5°10'N, 59°29'W, 420-450 m, 5 May 1989, Gillespie et al. 1262 (NY, US), 500 m, 17 Apr 1988, Hahn et al. 4703 (NY, US), 17 Apr 1988, Hahn et al. 4729 (CAY, NY, US); Demerara-Mahaica Region, from Timehri Airport to Kuru Kuru Creek, 6°25'N, 58°15'W, 10-30 m, Hahn et al. 3858 (NY); Kartabo, 6°21'N, 58°50'W, 22 Jan 1989, Hahn & Tiwari 5130 (NY, US); Upper Demerara region. Mabura Hill, 5°25'N, 58°40'W, 50 m, 21 Apr 1989, Hahn 5810 (NY); Region U. Takutu-U. Essequibo, SE Kanuku Mtns., Makaprima, 3°10'N, 59°16'W, 28 Oct 1991, Hoffman & Gopaul 450 (NY, US); Rupununi Distr., Kanuku Mtns., 3°9'N, 59°7'W, 2 Feb 1994, Jansen-Jacobs et al. 3537 (NY, U); Potaro-Siparuni Region, Kaieteur Falls National Park, 5°10'N, 59°29'W, 12 Jul 1993, Kelloff et al. 9/5 (NY); P'napma survey line, 4°40'N, 58°40'W, 21 Sep 1990, McDowell 3306 (NY); Potaro Siparuni region, Ciong valley, 9 km N of Kato Village, 4°42'N, 59°5'W, 1 Jun 1995, Mutchnick 1454 (NY); 4°34'N, 58°44'W, 21 Apr 1992, Pennington et al. 367 (U); Mabura Hill, 5°25'N, 58°40'W, 19 Nov 1986, Pipoly & Boyan 8848(NY); Mt. Ayanganna, Upper Mazaruni River basin, 700-800 m, 4 Aug 1960, Tillett 45037 (NY). (Henderson, A.J., Bactris (Palmae) in Flora Neotropica Monographs 79. 2000)A

Bibliography

    A. Henderson, A.J., Bactris (Palmae) in Flora Neotropica Monographs 79. 2000
    B. World Checklist of Arecaceae