Virola alvaroperezii D. Santam., 2022

Santamaria-Aguilar, Daniel & Lagomarsino, Laura P., 2022, New Species of Virola (Myristicaceae) from South America, PhytoKeys 197, pp. 81-148 : 81

2. Virola alvaroperezii D. Santam. sp. nov.

Type.

Ecuador. Carchi: Tulcan Cantón, Parroquia Tobar Donoso, Reserva Indigena Awa , Centro El Baboso , 00°53'N, 078°25'W, 1800 m, 17-27 Aug 1992 (♀ fl and fr), G. Tipaz, M. Tirado, C. Aulestia, N. Gale & P. Ortiz 1789 (holotype: MO-2 sheets! [flowers: accession 05005569, barcode MO-1528199; fruits: accession 05005570, barcode MO-1528198]; isotypes: QCNE [n.v.]). Fig. 7

Diagnosis.

Virola alvaroperezii is more similar to V. macrocarpa and V. otobifolia from Colombia, Panama, respectively. All these species have relatively large leaf blades and fruits, with lateral veins that are well separated and the abaxial leaf surface covered with stellate, sessile trichomes. Morphologically, it differs from V. macrocarpa and V. otobifolia by the abaxial leaf surface densely pubescent (vs. sparsely pubescent). Additionally, it differs from V. macrocarpa in having lateral veins that are more separated ([2-] 2.4-2.7 cm apart vs. 0.8-1.5 cm apart), and large fruits (4.3-4.5 × 3-3.6 cm vs. 2.7-3.3 × 2-2.3 cm). It differs from V. otobifolia by its wide fruit (3-3.6 cm vs. [1.9-] 2.3-2.9) and thin pericarp (2.8 mm vs. [2.7-] 3-4.7 mm).

Tree 30-40 m × 60-70 cm diameter, inner bark and exudate not described. Twigs 0.37-0.4 cm thick, terete to slightly compressed, inconspicuously pubescent, trichomes dendritic, sessile, ferruginous, without lenticels. Leaves young terminal bud not seen; petiole 1.5-2 × 0.34-0.5 cm, terete to slightly canaliculate, sometimes slightly winged, tomentose to tomentulose, the trichomes dendritic; leaf blades 26-28.5 × 12.1-14 cm, widely elliptic; adaxial surface of mature leaves drying brown to brown-olivaceous, the surface smooth, sometimes shiny, glabrous; abaxial surface drying dark brown-reddish to brown-whitish, densely pubescent, the trichomes stellate, ca. 0.1 mm diameter, sessile, the central part of the trichome dark reddish or colorless, the branches brown-reddish or colorless; lateral veins ca. 15, ca. 3 veins per 5 cm, spaced (2-) 2.4-2.7 cm, adaxially the same color as the leaf surface or slightly darker, flat to slightly raised, abaxially brown to blackish, raised, glabrescent above, densely pubescent to the sides, arcuate-ascending distally, slightly anastomosing near the margin and without forming a marked intramarginal vein; tertiary veins lightly visible on both sides, but especially below; midvein adaxially flat to slightly elevated, abaxially raised, rounded, glabrescent to tomentose; base obtuse, not revolute, flat; margin flat; apex absent. Staminate inflorescence and flowers unknown. Pistillate inflorescence ca. 4.2 cm long, axes flattened, tomentose, with trichomes dendritic, ferruginous; peduncle ca. 1.2-1.7 × 0.3-0.35 cm; main axes with 5 ramifications; bracts not seen. Pistillate flowers in terminal fascicles of 2-3 flowers, on a receptacle ca. 6 mm wide; perianth ca. 6 mm long, lanceolate, fleshy, brown when fresh, connate by ca. 3-3.2 mm long, external surface densely pubescent with ferruginous and dendritic trichomes, internal surface pubescent (especially on the lobes); lobes 3, ca. 2.8 × 1.2-1.5 mm and ca. 0.5-0.6 mm thick, without resinous punctuations when rehydrated; gynoecium ca. 2.5-3.1 × 1.5-1.6 mm, conical to subglobose, densely pubescent, the trichomes ferruginous; stigma 2-lobed, ca. 0.5 × 0.3 mm, erect, flat seen from above, drying blackish, slightly wavy at the margins. Infructescence ca. 4.5 cm long, with 1 or 4 fruits in immature infructescence, peduncle ca. 1.5 × 0.8 cm. Fruits 4.3-4.5 × 3-3.6 cm, brown when fresh (probably by the indument), ellipsoid, shortly stipitate, densely tomentose, the trichomes dendritic, sessile, ferruginous, not falling to the touch like dust, the surface rugose, the line of dehiscence smooth to faintly carinate, the base obtuse to truncate, the apex obtuse; pericarp 2.8 mm thick; pedicel 0.6-1 cm long. Seed ca. 2.7 × 1.6 cm, the testa dark brown to blackish when dry, sulcate; aril described once as red when fresh, dark brown when dry, the texture dry and thin, laciniate almost to the base, in narrow bands distally.

Distinctive characters.

Virola alvaroperezii is a distinctive species characterized by generally large, wide leaf blades with well-separated lateral veins that are abaxially covered with dense pubescence of stellate, sessile trichomes (Fig. 4B ) and large fruits (4.3-4.5 × 3-3.6 cm) with thick pericarp (2.8 mm) (Fig. 6B ). It is also distinctive for being a large tree (30-40 m tall).

Etymology.

It is a great pleasure to dedicate this new species to the Ecuadoran botanist Álvaro Javier Pérez Castañeda. He is an excellent botanist, collector and expert of the flora of Ecuador, especially the flora of Yasuní. Among other contributions, he has described at least 26 from different angiosperm families (e.g., Pérez et al. 2013; Torke and Pérez 2013; Kawasaki and Pérez 2015, 2016) and is coauthor of Árboles emblemáticos de Yasuní, Ecuador ( Pérez et al. 2014) and the treatment of Myrtaceae for the Flora of Ecuador ( Kawasaki et al. 2019). Pérez Castañeda collected specimens of some of the Virola species described here.

Distribution.

Virola alvaroperezii is know from Carchi and Esmeraldas provinces in Ecuador (Fig. 18A ). It grows in primary vegetation in premontane rain and very wet forest from (500-) 1600-1800 m.

Phenology.

Only a single studied specimen of Virola alvaroperezii has pistillate flowers; it was collected in August. Staminate flowers were not observed in the studied material. Fruits were collected in August and September.

Common name and uses.

Guangare macho (Ecuador; C. Aulestia & M. Aulestia 1017).

Preliminary conservation status.

Virola alvaroperezii is Endangered following IUCN criteria B1a and B2a. It is known from three localities, has an EOO of 966 km2, and an AOO of 12 km2. Further justifying this status, this new species occurs in a region of very high rates of deforestation due to agricultural pressures ( Kleemann et al. 2022). The only specimens of V. alvaroperezii that we were able to verify were collected on the Awá Reserve, and this species may be locally protected by sustainable forestry practices by the Awá indigenous community ( Oviedo 2006).

Discussion.

Herbarium specimens of Virola alvaroperezii have been confused with another montane species, V. macrocarpa from Colombia (1100 m elevation). It could be confused with another Colombian species, V. cogolloi (840-1500 m elevation), which is formally described here, as well with V. otobifolia D. Santam., recently described from Panama (50-850 m elevation) ( Santamaría-Aguilar et al. 2019). All these species have relatively large leaf blades and fruits, with lateral veins that are well separated and the abaxial leaf surface covered with stellate, sessile trichomes. Differences among the three species are summarized in Table 2 .

Notes.

The holotype deposited at Missouri Botanical Garden (MO) represents a single collection mounted on two sheets that are clearly labeled (i.e., "Sheet 1 of 2" and "Sheet 2 of 2") as being parts of the same specimen (ICN Art. 8.3; Turland et al. 2018); one of the sheets carries pistillate flowers (MO-05005569) and the other, fruits (MO-05005570).

Leaf size and the number of lateral veins may be higher than presented here, as most of the material examined had broken leaves.

The collection C. Aulestia & M. Aulestia 1017 (MO) from Esmeraldas Province, Ecuador bears a fruit (possibly immature) that is smaller (ca. 3.7 × 2.6 cm) with thinner pericarp (ca. 2 mm) than other specimens of V. alvaroperezii . However, it otherwise matches very well including in its leaf morphology, tall tree habit, and occurrence Río Mira basin; for this reason, it is included in the concept we have adopted, although the fruit measurement is not included in the description.

The fruit specimen H. Vargas et al. 4603 (MO, QCNE [image!]), also from Esmeraldas Province, Ecuador, could not be confirmed to the species. It is similar to V. alvaroperezii in its leaf morphology (e.g. size, pubescence and trichomes, lateral vein spacing); however, its fruits are rounded and smaller (ca. 3.2-3.3 × 2.6-2.7 mm) with a conspicuous carina.

The two collections of V. macrocarpa from Carchi Province that are cited in Flora of Ecuador ( Jaramillo et al. 2004) correspond to this new species.

Specimens examined.

Ecuador. Carchi: Tulcán cantón, Reserva Indígena Awá, Comunidad El Baboso , 12 km al norte de Lita, 00°53'N, 078°20'W, 1600 m, 20 Sep 1991 (fr), D. Rubio et al. 2205 (MO!, QCNE [n.v.]) . Esmeraldas: Reserva Etnica Awá, Parroquia Ricaurte, Centro Pambilar , 01°08'N, 078°36'W, 500 m, 21 Jan 1993 (fr), C. Aulestia & M. Aulestia 1017 (MO!, QCNE [n.v.]) .

Figures

Figure 3. Fruit morphology of Virola, note shape, pericarp, indument, and arils. Also see the green color of pericarp, and the minutely pubescent, falling easily as dust (A-D, F), and the yellow pericarp (J-M) A Virola sp B V. allenii C V. elongata D V. otobifolia E Virola sp F V. sebifera G Virola sp H Virola sp I V. surinamensis J V. fosteri K V. cf. nobilis L V. laevigata M V. koschnyi N V. chrysocarpa. Photos by Reinaldo Aguilar (B, F, K, L, M, N), Christopher Davidson (A, C, G), Robin Foster (E, H), Alwyn H. Gentry (D), Manuel Morales (J), Luiz O. A. Teixeira (I).

Figure 4. Comparation of pattern of the lateral veins and trichomes on abaxial leaf surface (below) of the newly described species of Virola and species that are morphologically similar A Virola aguarunana (C. Diaz et al. 7700 A, MO) B V. alvaroperezii (G. Tipaz et al. 1789, MO) C V. bombuscaroensis (J. Homeier 4507, MO) D V. calimensis (M. Monsalve 1769, MO) E V. calophylla (J. E. L. da S. Ribeiro et al. 1138, MO) F V. calophylloidea (C. C. Berg et al. P 18793, MO) G V. cogolloi (A. Cogollo et al. 4198, MO) H V. excisa (C. E. Ceron & F. Hurtado 4147, MO) I V. obovata (R. Vasquez & N. Jaramillo 3822, MO; below from A. [H.] Gentry & J. Revilla 20448, MO) J V. macrocarpa (A. E. Lawrence 675, K below A. E. Lawrence 675, MO) K V. parkeri (A. Monteagudo et al. 10761, MO; below from M. Huaman et al. 334, MO) L V. peruviana (W. H. Lewis et al. 10074, MO) M V. sebifera (R. Aguilar 2171, MO) N V. tuckerae (A. Cogollo et al. 4147, MO) O V. yasuniana (H. Vargas & J. Cerda 678, MO). Scale bars: 1 cm.

Figure 6. Comparison of fruits of newly described Virola species, with those species that are morphologically similar to them, noting the shape, indument, a pericarp thickness A V. aguarunana (C. Diaz et al. 7195, MO) B V. alvaroperezii (D. Rubio et al. 2205, MO) C V. bombuscaroensis (J. Homeier 4507, MO) D V. calimensis (M. Monsalve 158, MO) E V. calophylla (J. J. Pipoly 15614, MO) F V. calophylloidea (S. R. Lowrie et al. 54, MO) G V. cogolloi (D. Cardenas & E. Alvarez 3239, MO) H V. macrocarpa (A. E. Lawrance 675, MO) I V. excisa (W. Palacios 3186, MO) J V. obovata (R. Vasquez & N. Jaramillo 3822, MO) K V. peruviana (D. N. Smith & V. Garcia 13841, MO). L V. parkeri (A. Monteagudo et al. 10761, MO) M V. yasuniana (A. Perez & W. Santillan 4361, MO; right and below from V. Zak & S. Espinoza 5149, MO) N V. tuckerae (A. Cogollo et al. 3924, COL). Scale bars: 1 cm.

Figure 7. Virola alvaroperezii A branch with pistillate inflorescence B lateral view of pistillate perianth (right), as well as a medial section (left) showing the internal side and gynoecium C medial sections of gynoecium, with enlargement of trichomes (right) and stigma (top) D lateral view of gynoecium after perianth has fallen E leaf blade with infructescence F abaxial surface of leaf blade showing the midvein with enlargement of trichomes G fruit with detail of indument (right). Drawn by Bobbi Angell based on G. Tipaz et al. 1789 (A-B MO- 05005569), and G. Tipaz et al. 1789 (C-G MO- 05005570).

Figure 18. Geographic distribution of the new species of Virola.