Mansoa gentryi M.M.Silva-Castro, 2016

Silva-Castro, Milene Maria Da & Queiroz, Luciano Paganucci De, 2016, Five new species of Mansoa DC. (Bignoniaceae) from South America, Phytotaxa 258 (1), pp. 49-62 : 50-53

Mansoa gentryi M.M.Silva-Castro , sp. nov. ( Fig. 1 )

Similar to Mansoa alliacea ( Lamarck 1785: 421) Gentry (1979: 772) in its short inflorescences, from which it differs by the linearflattened fruit, 38–40 cm long, with an acuminate apex (vs. oblong-cylindrical fruit, 8.5–9 cm long, with a rounded apex in M. alliacea ), and by the leaflets with a nectary field between the main and secondary veins on the abaxial surface (vs. leaflets without nectaries in M. alliacea ).

Type:— PERU. San Martin: Mariscal Caceres, Tocache Nuevo, remnant gallery forest along Rio Huallaga, 10 March 1979, A. Gentry 25477A (holotype MO 27433312!, isotypes MO, NY!).

Lianas with galic odor; branches non-viscid, cylindrical to subquadrangular, glabrous to puberulous, interpetiolar areas with field of patteliform nectaries, bark striated; prophylls of the axillary buds 3–7 mm long, lanceolate, glabrous to puberulous. Leaves 2-foliolate; petiole 2–2.4 cm long, glabrous to puberulous; petiolules 1.5–3 cm long, glabrous to puberulous, with indentations or wrinkles at the apex; leaflets 14–21 × 8–14 cm, chartaceous, elliptic, apex acute to rounded, occasionally mucronulate, margins entire, revolute, base cuneate to slightly attenuate, 3-nerved, concolorous, adaxial and abaxial surfaces lepidote, with patteliform nectaries at the axil of main veins near the leaflet base; tendrils trifurcate. Racemes axillary, lax, few-flowered, the main axis 3–8 cm long, cylindrical. Calyx 6–6.4 × 8–8.5 mm, light green, coriaceous, campanulate, truncate, venation not prominent, veins not extending above the calyx rim, puberulous, without nectaries; corolla 7–7.3 × 3–3.5 cm, purple with whitish tube, membranous, tubular-campanulate, externally glabrous at the basal third and pubescent at the mid-apical region, lobes with a rounded apex; stamens included, dorsal filaments 2.5–2.7 cm long, ventral filaments 2–2.2 cm long, connective not elongated, glabrous, thecae 5–5.2 mm long; staminode 5.5–6 mm long; nectariferous disk ca. 1.3 mm long, 3–3.6 mm diam., annular; ovary 9–9.3 × 2–2.3 mm, cylindrical, lepidote, 2-series of ovules per locule, style 2.5–2.7 cm long, stigma 4.5–5 mm long, lanceolate. Capsule (immature) 38–40 × 2.8–3 cm, linear, subcylindrical, apex acuminate, margins entire, base truncate; valves coriaceous to woody, not striated, not verrucose, lepidote, veins prominent, forming 1 midrib; calyx not persistent. Seeds not seen.

Distribution:—This species is only known from riparian forests of Peru, where it occurs in the Departments of Huánuco, Loreto, Madre de Dios, Pasco and San Martin ( Fig. 2A ).

Phenology:—This species was collected in flower in January, March, and June. Fruiting specimens were collected from June to August.

Conservation status:—Data Deficient (DD) ( IUCN 2012). Better assessment in its natural environment is still required. The most recent herbarium material was collected more than 20 years ago.

Etymology:—This species is named after Alwyn H. Gentry, who played a key role in the advancement of our knowledge of the Bignoniaceae systematics.

Notes:— Mansoa gentryi shares several morphological features with Mansoa alliacea such as the chartaceous, elliptic leaflets and short inflorescences. As such, herbarium specimens of M. gentryi were usually identified as M. alliacea . A.H. Gentry was the first taxonomist to note that this plant could be a new species, having attached the following note to the specimen J. Schunke V. 3362 (NY): “ Mansoa sp. nov. aff. alliaceum. ” Mansoa gentryi differs from M. alliacea by the longer fruits (38–40 cm long) with an acuminate apex (vs. fruits 8.5–9 cm long, with a rounded apex in M. alliacea ) and by the nectaries found on the axils of the abaxial veins of leaflets (vs. leaflets without nectaries in M. alliacea ). Mansoa gentryi is also characterized by the leaflets with entire and revolute margins, truncate calyx, purple corolla, non-elongated, glabrous and linear stamen connective, and subcylindrical capsule with a raised midrib, and strong garlic odor.

Additional specimens examined (paratypes):— PERU: Amazonas: Lugar Aintami, Orilla de Cenepa , 19 January 1973, R. Kayap 186 (NY) ; Huánuco: Pachitea, Honoria, Bosque Nacional de Iparia : Región de “bosque seco tropical” a lo largo del RíoPachite a cerca del campamento Miel de Abeja (1 km arriba do pueblo de Tournavista o unos 20 km arriba da confluência con el Río Ucayali), 300–400 m, caminho a Ayamiría a 3 km de Miel de Abeja , 20 January 1967, J. Schunke Vigo 1551 (G, MO, NY) ; Loreto: Alto Amazonas, Río Pastaza, una hora arriba de la boca del Lago Rimachi , ambas margenes, 25 January 1979, C. Diaz & J. Ruiz 911 (INPA, MO, NY) ; Tall Forest at Pucallpa , 1 December 1965, J. Schunke Vigo 985 (MO, NY) ; Pasco: Drainage of Rio Palcazu entre km 51 e 60 of new road in construction NW of Villa Rica toward Puerto Bermudez , 700 m, wet tropical forest in steep foothills, 4 March 1982, A. Gentry & D. Smith 36043 (MO, NY) ; San Martin: Mariscal Caceres , 21 August 1969, J. Schunke Vigo 3362 (NY) .

Figures

FIGURE 1. Mansoa gentryi.A. flowering branch. B. detail of the interpetiolar field with patelliform nectaries. C. abaxial leaflet surface showing the position of nectaries (dots). D. petiole apex. E. calyx. F. open corolla showing the included androecium. G. detail of the connective. H. pistil. I. ovary cross-section showing 2-series of ovules per locule. J. immature capsule.K. cross-section of capsule. (Drawn by Ivan Farias Castro; A–I from R. Kayap 186; J–K from A. Gentry 25477A).

FIGURE 2. Distribution range of the newly described species of Mansoa. A. Mansoa gentryi. B. Mansoa ivanii. C. Mansoa longicalyx. D. Mansoa minensis. E. Mansoa paganuccii.