Glandonia macrocarpa Griseb., 1858

Guesdon, Isabel Reis, Amorim, André Márcio & Meira, Renata Maria Strozi Alves, 2018, The hydrochorous Amazonian genus Glandonia (Malpighiaceae): new records, morphoanatomy updates and taxonomic contributions, Phytotaxa 345 (1), pp. 13-25 : 20-21

1. Glandonia macrocarpa Griseb. in Mart., Fl. bras. 12 (1): 24. 1858.

Type: — BRAZIL. Amazonas. Manaus, Rio Negro , December-March 1850–1851, Spruce 1090 (holotype M; isotypes G, GH, GOET, K, NY!, P!). ( Figures 1B ; 2A, B ; 3D, H, I, K, L ; 4A, F, H, K ; 5A–C )

Description —Trees, 12–20 m tall; branches glabrous. Leaf entire; lamina (10–)12–26 × (3–) 5–11 cm, strongly obovate, base cuneate, apex acuminate, margin flat or slightly revolute, papyraceous, adaxial and abaxial surfaces sparsely sericeous to glabrescent, abaxial surface with (0)2–4 basilaminar yellow glands, conspicuous, positioned laterally at the midrib, ca. 1.3 mm diameter, smaller inconspicuous glands present, 0.5–0.6 mm diameter, randomly distributed on the blade; petiole (7–)8–20(–26) mm, glabrous; stipules (8–) 10–20 mm long, glabrous. Inflorescence a raceme of cincinni, (13–) 17–28 cm long, appressed-tomentose, cincinni with 3–5 flowers; bracts ovate-linear, 3.5–6.4 mm long, eglandular; bracteoles ovate apex rounded to slightly acute, concave, abaxially sericeous, 1.5–4 mm long, bracteole gland creamy white, discoid-convex secretory surface. Floriferous peduncle ca. 1–2 mm long. Pedicel 10– 15 mm long, appressed-tomentose. Sepals 1.5–2 mm long beyond sepal glands, apex rounded, abaxially sericeous, sepal glands 2–3.5 mm long, white. Petals glabrous, outermost petal helmet-shaped, white, limb 5–6.5 × ca. 5.5 mm, denticulate, claw 4–6 mm long, reflexed; lateral petals white, limb 5–6.5 × 5–6.5 mm, sagittate, eglandular, margin entire, claw 4.5–6 mm long, reflexed; posterior petal yellow, limb ca. 6 × 5 mm, reflexed, sagittate, with 5–9, marginal glands on the proximal portion, ca. 1 × 0.4 mm, claw 4–5 mm long, erect. Filaments 1–1.5 mm long, densely hirsute just above of the insertion of the anther; anthers 4.3–5.5 mm long. Ovary ca. 1.5 mm long, pyramidal, glabrous; styles three, 5–5.5 mm long, subequal, glabrous, 0.5–1 mm bent at apex toward the center of flower. Fruits (1.8–)1.9–2.8 × 0.7–1.8 cm, cylindrical, becoming truncate-conoid, with 17–20 longitudinal grooves, forming rounded projections at the base, styles persistent.

Specimens examined— BRAZIL. AMAZONAS: Manaus , BR 17 Km 21, 28 December 1955 (bud, fl), Coelho & F. Mello s.n. ( INPA 3230 ) ; ibid., BR 17 Km 17, 14 December 1955 (bud, fl), D. Coelho s.n. ( INPA 3118 ) ; ibid., 28 December 1955 (fl), Luis e Francisco s.n. ( IAN 110940 ) ; ibid., Cachoeira baixa do Tarumã, 18 November 1955 (bud), W. Rodrigues s.n. ( INPA 2934 ) ; ibid. 6 December 1955 (bud, fl), D. Coelho s.n. ( IAN 92214 ; INPA 3041 ) ; ibid., 07 November 1958 (bud, fl), s.n. ( INPA 6047 ) ; ibid., 26 December 1962 (bud, fl), W. Rodrigues et al. 4945 ( INPA) ; ibid., Estrada do Aleixo , 2 December 1942 (fl), A. Ducke 63 ( IAN, MG) ; ibid., Estrada dos Franceses, 28 November 1955 (bud), W. Rodrigues s.n. ( INPA 2979 ) ; ibid., Estrada Torquato Tapajós , 1 April 1975 (fr), A. Loureiro et al. s.n. ( INPA 48328 ) ; ibid., Igapó dos riachos, 2 November 1929 (bud), A. Ducke s.n. ( INPA 16283 ) ; ibid., Igarapé do Crespo , 13 February 1943 (fr), A. Ducke 1182 ( IAN) ; ibid., Igarapé do Goiabinha , 15 March 1958 (fr), Collector s.n. ( IAN 98780 ) ; ibid., 19 March 1958 (fr), s.c., s.n. ( INPA 622 ) ; ibid., Igarapé Santa Maria , 24 February 1956 (fr), J. Chagas & D. Coelho s.n. ( IAN 110956 ; INPA 3505 ) ; ibid., Ponta Negra , 11 February 1977 (fr), M. F. Silva et al. 2065 ( INPA) ; ibid. Reserva Adolpho Ducke , December 1901 (fr), s.c. 5956 ( MG) ; ibid., 7 April 1994 (fr), J. E. L. S. Ribeiro 1262 et al. ( INPA) ; ibid., 27 November 1997 (bud, fl), P. A. C. L. Assunção 725 et al. ( IAN; INPA) ; ibid., 18 January 2007 (bud, fl) ; ibid. I. R. Silva-Guesdon 16 ( INPA) ; ibid., 14 December 2014 (bud, fl), I. R. Silva-Guesdon 287 ( VIC) ; ibid., 20 December 2014 (bud, fl), ibid. I. R. Silva-Guesdon 288 ( VIC) ; ibid., Rio Preto , 30 January 1962 (fr), W. Rodrigues & J. Chagas 4168 ( INPA) ; ibid., Rio Cuieiras , 19 December 1961 (bud, fl), W. Rodrigues & B. Willson 3986 ( INPA) .

Notes on morphoanatomy— Field observations revealed that the leaf glands ( Fig. 3D ) and posterior petal ( Fig. 3K ) are yellow, while the bracteole gland is creamy white ( Fig. 3I ) and the sepal glands are white ( Fig. 3K, L ). The outline of the anticlinal walls is sinuous, and indument scars on the leaf surfaces ( Fig. 4A ) were observed. The anatomical study revealed small leaf glands thought the blade ( Fig. 3H ) that are difficult to see with the naked eye (as in Glandonia prancei , Fig. 4J ). The vascular system in the petiole is arranged as a concentric arc delimiting a central pith ( Fig. 4H ). The section of the bracteole glands revealed a convex secretory surface ( Fig 4K ). In addition, the posterior petal limb has bigger marginal glands than G. prancei and G. williamsii ( Fig. 5B, C ).

Distribution, habitat and conservation— This species is frequent in lowland (terra firme) from Manaus ( Fig. 1A ), mainly into the same conservation areas. According to IUCN (2012) criteria, Glandonia macrocarpa is Endangered (EN), with an EOO <2,000 km 2 and AOO = 16 km 2 (B1 + B2 subcriterias). During our study we found three voucher specimens from igapó in the upper Rio Negro, L. A. Maia, 571 (NY!, INPA), J. M. Poole, 1982 (NY!), M. L. Alencar 571 (NY!) that have been identified as G. macrocarpa . However, these specimens exhibit atypical characters such as elliptical leaf shape, with rounded base and conspicuous laminar leaf glands. Additional studies are needed to confirm the occurrence of G. macrocarpa across the Rio Negro basin.

Phenology— Glandonia macrocarpa has been collected in flower from November to January and in fruit from January to May.

Figures

FIGURE 1. A. Map showing the distribution of Glandonia macrocarpa (black triangles), G. prancei (black circles) and G. williamsii (black squares). B. Glandonia macrocarpa specimen (arrow) in terra firme forest. C. Glandonia williamsii specimen (arrow) in igapó. D. Hydrochorous fruit of G. prancei.

FIGURE 2. General view of Glandonia species: A and B Glandonia macrocarpa: A. Flowering branch, B. lateral and frontal view of fruit. C. Fruiting branch of G. williamsii. D. Fruiting branch of G. prancei. Drawing A from Guesdon 16 (INPA), B from Ducke 793 (INPA), C from Fróes 28782 (MG) and D from Prance et al. 20557 (INPA).

FIGURE 3. Vegetative and reproductive characters of Glandonia species: A. keel-shaped leaves of G. williamsii, B. and C. general view of leaves and inflorescence of G. prancei. Basilaminar leaf glands: D. Glandonia macrocarpa, E. Glandonia prancei and F. Glandonia williamsii. Laminar leaf glands: G. Glandonia williamsii and H. Glandonia macrocarpa. Floral glands: I. bracteole gland (BG) of G. macrocarpa, J. bracteole and sepal glands of G. prancei (BG and SG, respectively), black arrow: pedicel joint. K. Posterior petal in bud of G. macrocarpa, note the petal glands (arrow) L. Helmet-shaped petal (HP) and reflexed limb of posterior petal (PP) in G. macrocarpa.

FIGURE 4. Anatomical characters of Glandonia species. A. Adaxial surface of G. macrocarpa showing indument scars (black arrow). B. Abaxial surface of G. prancei showing a stoma (black arrow) and sinuous outline of the anticlinal epidermal wall. Abaxial surface of G. williamsii C. papillae covering a stoma (black arrow), D. papillose surface (SEM image), a stoma (white arrow). E. Transversal section of leaf of G. williamsii, papillae (white arrow), F. Sclereids in midrib of G. macrocarpa (black arrow). Diagrammatic schemas of petiolar vascular systems G. a curved arc with invaginated ends in G. prancei and H. a concentric arc delimiting a central pith in G. macrocarpa, dot-filled areas: phloem, striped areas: xylem. Leaf blade cleared I. in G. williamsii and J. in G. prancei, note the laminar gland (arrow). Transversal view of bracteole gland K. convex surface in G. macrocarpa, L. truncate surface in G. prancei. M–O. Sclereids on posterior petal of G. williamsii, N. Macrosclereids, O. Brachysclereids.

FIGURE 5. Morphoanatomical floral characters of Glandonia species. A–C: Glandonia macrocarpa: A. General view of the flowers, B. Posterior petal margin (SEM image) and C. Posterior petal cleared. D–F: Glandonia prancei: D. General view of the flowers, E. Posterior petal margin (SEM image) and F. Posterior petal cleared; G–I: Glandonia williamsii: G. General view of the flowers H. Posterior petal margin (SEM image) and I. Posterior petal cleared. PP: Posterior petal. SG: Sepal glands. BG: Bracteole gland.