Otoba squamosa D. Santam., 2021

Santamaria-Aguilar, Daniel & Lagomarsino, Laura P., 2021, Two new species of Otoba (Myristicaceae) from Colombia, PhytoKeys 178, pp. 147-170 : 147

Otoba squamosa D. Santam. sp. nov. Fig. 7

Type.

Colombia. Antioquia: Urrao, Vereda Calles, Parque Nacional Natural "Las Orquídeas”, margen derecha Quebrada La Honda, 06°32'N, 076°19'W, 1330-1400 m, 08 May 1993 (fr), Á. Cogollo, R. Carmona, E. Álvarez 6197 (holotype: MO-05011088! [1500541]; isotypes: n.v.).

Diagnosis.

Otoba squamosa is similar to O. gordoniifolia from Colombia and Ecuador, and both species grow in montane forest in the Andes. However, it differs in its leaves with shorter petioles (1.7-2.7 [-3.8] vs. [3-] 5-7 cm long) and smaller lamina (6.7-14.5 vs. [13-] 24-34 cm long), staminate flowers with a perianth with a swollen ring (vs. without) and smaller anthers (0.5-0.7 vs. 0.7-1.5 mm long), pistillate flowers with a glabrous ovary (vs. pubescent), and fruits with thin pericarp (2.6-3 vs. 3-5 mm thick).

Description.

Tree 8-18 (-24) m tall × 11.9-34.7 cm diam., external and internal bark not described. Exudate hyaline, oxidizing reddish, only reported from in flowers and fruits. Twigs 0.13-0.27 cm thick, terete to slightly flattened laterally, the external bark brown to blackish, with malpighiaceous trichomes 0.2-0.6 mm long, brown to ferruginous, the indument denser in young parts. Young foliar bud 1.6-4.3 (-5.8) cm long, densely pubescent. Leaves: petiole 1.7-2.7 (-3.8) × 0.1-0.2 (-0.25) cm, canaliculate, very short-winged; lamina 6.7-14.5 × 3.4-6 (-8) cm, elliptic, rarely widely elliptic; adaxial side glabrous, usually drying dark brown to blackish, the surface muricate-reticulate; abaxial side usually drying pale to dark brown, the surface muricate, sparsely pubescent, with malpighiaceous trichomes 0.3-0.6 mm long, sessile, ferruginous, and scale-like trichomes ca. 0.1 diam. with the central part dark, contrasting with the lighter sides, crystals generally absent and if present very few; vernation line imprints 2 parallel lines, 0.7-1.5 (-1.8) cm from the margin, the panel area 1.8-2.5 (-3.4) cm wide (in the central portion), the same color as the surface; midvein flat on adaxial side, the same color as the surface or blackish, abaxially 0.5-0.9 mm wide, raised, a little darker than the surface; secondary veins brochidodromous, the loops 0.2-0.3 cm from the margin, lateral veins 13-17 per side, (3-) 4-6 veins per 3 cm, on adaxial side slightly caniculate, on abaxial side flat to slightly raised, not very conspicuous, arcuate distally, the marginal vein not visible on adaxial side, slightly visible on abaxial side; tertiary veins indistinct; base acute to cuneate, not revolute; margin entire, not revolute; apex acute, the acumen 0.3-0.9 cm long. Staminate inflorescence: axillary and/or ramiflorus, with 1-2 main axes, spiciform, these axes 2-7 cm × 0.6-1.2 mm, pubescent, the trichomes ferruginous, each axis compound with 2-5 fascicles of flowers, each fascicle with 3-6 flowers, alternate; bracts ca. 1.5-1.6 × 1 mm (observed in very young inflorescences), densely pubescent outside, the trichomes ferruginous; pedicel 1.3-4 mm long, pubescent; bracteoles absent. Staminate flowers: flower bud 2-3 × 1-1.5 mm; perianth 3.5-4.7 mm long, yellowish to yellowish-green (in fresh material), fleshy (hardening near the base by the ring), connate by 1-1.7 mm; lobes 3 (4), (2-) 2.5-3.4 × (0.9-) 1.4-2 mm, without resinous punctuations or lines, pubescent outside, the trichomes ferruginous, inside glabrous, smooth to lightly spongy, the apex in some flowers with a minutely inflexed-apiculate, the margin edges slightly turned inwards, slightly wavy; ring present, 0.1-0.4 mm wide, lobed, smooth, or sometimes spongy; filament column 1.5-2.1 mm long, usually cylindrical, slightly narrow towards the apex, fleshy, glabrous; anthers 3 (4), 0.5-0.7 mm long, free, lanceolate to oblong, apex slightly incurved. Pistillate inflorescence: axillary, 1.4-3.2 cm long, pubescent, the trichomes ferruginous, each axis compound with 1-2 fascicles of flowers, each fascicle with 2-3 flowers, alternate; bracts not seen; pedicel 3-4 mm long, pubescent; bracteoles absent. Pistillate flowers: flower bud 3-4 × ca. 2 mm; perianth 3-5 mm long, the color and texture as in the staminate flower, connate by 1-1.5 mm; lobes 3 (4), 2-3.5 × 2-2.5 mm, without resinous punctuations or lines, pubescent outside, the trichomes ferruginous, inside glabrous; ring present; gynoecium 2-3 × 1.5-2.3 mm, glabrous, ovary sessile to short-stalked, ca. 0.6 mm long; stigma 2-lipped, subsessile; stigmatic lips ca. 0.6 mm long. Infructescence probably with one fruit (fruits separated from the axis in all specimens observed); pedicel ca. 1-1.1 cm long. Fruits (2.5-) 3.4-3.6 × (1.9-) 2.8-3 cm, green, globose, the surface glabrous, rugose, sometimes with whitish to brownish lenticels, the line of dehiscence smooth, the base obtuse, and sometimes getting narrower towards the pedicel, apex obtuse or acute, the acumen 0.8-1 cm long; pericarp 2.6-3 mm thick; seed (2.1-) 2.5-2.9 × (1.7-) 2.3-2.4 cm, similar in shape to the fruit, whitish or brown (in dry material), gibbose at the apex or nearly so, the testa 0.4-0.6 mm thick; aril described once as white (D. Sánchez et al. 1529), brownish to white-yellowish in dry material, waxy to dry in texture.

Distinctive characters.

Otoba squamosa is recognized by a variety of leaf traits, including: squamate or scale-like indument mixed with malpighiaceous trichomes on the abaxial surface, lateral veins that are more or less conspicuous, forming a marginal vein, and vernation lines that parallel the midvein. Additionally, the staminate flowers have a perianth with swollen-lobed ring in the inner surface, a typically cylindrical filament column with lanceolate to oblong anthers and pistillate flowers that have a glabrous gynoecium. Finally, the fruits are relatively large, with thick pericarp.

Etymology.

The specific epithet refers to the squamate or scale-like indument that is present with more typical malpighiaceous trichomes on the abaxial surface of the leaf blades. The squamate or scale-like indument is not unique to this species; it is also present in most specimens of O. acuminata , O. glycycarpa , O. scottmorii , and O. vespertilio ; also Smith and Wodehouse (1938), they described for O. lehmannii (as Dialyanthera Lehmannii).

Common name.

None recorded.

Distribution.

Otoba squamosa is known from the Cordillera Occidental of Colombia, specifically in the municipalities of Frontino and Urrao in the Department of Antioquia (Fig. 4 ). It grows in premontane forest between 1330-1450 m.

Phenology.

Fertile herbarium specimens of Otoba squamosa have been collected with staminate flowers in May and December, with pistillate flowers in May, September, and December, and with fruits in March, May, September, October, and December.

Preliminary conservation status.

Otoba squamosa is Endangered following IUCN criteria B2a. Justifying this status, it is known from only two localities and has an AOO of 4 km2; there are too few verified localities to reasonably estimate the EOO. The Andean forests of the Antioquia Department of Colombia where it occurs are particularly at risk for deforestation ( González-Caro and Vásquez 2017).

Discussion.

The collections now identified as Otoba squamosa were previously included under the concept of O. gordoniifolia (Fig. 8 ), and identified as such in herbarium specimens and in the literature (e.g., Cogollo 2011). These species share similarities: both grow in montane forests and have the leaf blades with conspicuous vernation lines (Figs 7A, F , 8B ), long petioles (shorter in the new species), lanceolate to oblong anthers, and fruit with thick pericarp. However, Otoba squamosa differs in its smaller leaf blades with thinner petioles, staminate flowers with a shorter perianth with a swollen-lobed ring in the inner surface and smaller anthers, and pistillate flowers with glabrous ovaries. See Table 3 for a comparison of these distinguishing characteristics. In addition, O. squamosa 's leaf blades are less pubescent abaxially, the terminal young foliar bud is shorter, and petioles are shorterwinged.

Within Otoba , the swollen-lobed ring in the staminate perianth is shared between O. cyclobasis (and even gives this species its specific epithet; Jaramillo and Balslev 2001) and O. squamosa ; in addition to this feature, both species have glabrous ovaries. However, the new species has longer petioles (1.7-2.7 [-3.8] vs.1-1.5 cm) and leaves (6.7-14.5 vs. 3.4-6 [-8] cm), lanceolate to oblong anthers (vs. globose), and larger fruits ([2.5-] 3.4-3.6 vs. 1.5-2.5 cm long); further, O. squamosa grows at higher elevations (1330-1450 vs. 150-300 m).

In the "Key to the species (pistillate or fruiting plants)" from Jaramillo-Vivanco and Balslev (2020), Otoba squamosa matches the recently described O. vespertilio from Costa Rica and Panama, though it is clearly not conspecific. Otoba squamosa differs from O. vespertilio in its longer petioles (1.7-2.7 [-3.8] vs. 0.8-2 cm long), abaxially conspicuous vernation lines (vs. absent), staminate perianth with a swollen-lobed ring (vs. without), and larger fruits ([2.5-] 3.4-3.6 vs. 2.2-2.7 × 1.6-1.7 cm) with thicker pericarp (2.6-3 vs. 1.3-1.8 mm).

Notes.

The specimen [J.] Pipoly 17003 (MO nv), included in Jaramillo-Vivanco and Balslev (2020), was collected in the same area of the type and other material of O. squamosa cited here, and we suspect that it corresponds to this new species, though this specimen was not located in our study.

Specimens of O. squamosa , including the type, have been previously identified in herbaria as O. gordoniifolia , and duplicates may have been distributed under these names.

The following sterile specimens from MO were collected in the same locality as fertile material or nearby (Parque Nacional Natural "Las Orquídeas”, Sector Calles); because they were not fertile, they were not used in the description presented above, though we believe that they correspond to this new species: Á. Cogollo et al. 6069, 6132, 6169, 6298, 6344, 6642, 6644, 6657, 6683, 6684, 6869, 6926, 6929, 7109, 7180, 7221, 7237, 7238, 7259, 7262, 7268, 7269; and J. Pipoly et al. 16663, 17022, 17033, 17042, and 17076.

Specimens examined.

Colombia. Antioquia: Frontino, Corregimiento Nutibara, cuenca alta del Rio Cuevas , bosque al lado carretera a La Blanquita , 1100 m, 21 Sep. 1987 (♀ fl & fr), D. Sánchez et al. 1529 (MO); Urrao , Parque Nacional Natural "Las Orquídeas”, Sector Calles , margen derecha del Rio Calles , 06°32'N, 076°19'W, 1420 m, 25 Mar. 1988 (fr), Á. Cogollo et al. 2573 (MO); Vereda Calles, Parque Nacional Natural "Las Orquídeas”, margen derecha Quebrada La Honda , 06°32'N, 076°19'W, 1330-1400 m, 03 May 1993 (♂ fl), Á. Cogollo et al. 6074 (MO) ; ibid, 08 May 1993 (♂ fl), Á. Cogollo et al. 6190 (K-2 sheets [n.v.], MO) ; ibid, 08 May 1993 (♀ fl), Á. Cogollo et al. 6198 (MO) ; ibid, 11 May 1993 (♂ fl), Á. Cogollo et al. 6279 (MO, NY) ; ibid, 11 May 1993 (♂ fl), Á. Cogollo et al. 6300 (K n.v., MO); Vereda Calles, Parque Nacional Natural "Las Orquídeas”, margen derecha del Rio Calles , en el filo NW de la Cabana de Calles , 06°32'N, 076°19'W, 1450 m, 15 Oct. 1993 (fr), Á. Cogollo et al. 6918 (MO) ; ibid, 18 Oct. 1993 (fr), Á. Cogollo et al. 7107 (MO) ; ibid, 08 Dec. 1993 (fr), Á. Cogollo et al. 7959 (GH digital image, K [n.v.], MO, NY); Las Orquídeas, Vereda Calles, Parque Nacional Natural Las Orquideas , Quebrada Honda , 06°29'N, 076°14'W, 1300 m, 08 Dec. 1992 (fr), J. Pipoly et al. 16745 (MO) ; ibid, 1330 m, 08 Dec. 1992 (♀ fl), J. Pipoly et al. 16798 (MO) ; ibid, 10 Dec. 1992 (♂ fl), J. Pipoly et al. 16902 (MO) ; ibid, 1300 m, 11 Dec. 1992 (♂ fl), J. Pipoly et al. 17019 (K [n.v.], MO); Parque Nacional Natural Las Orquídeas, Vereda Calles , margen derecha del Rio Calles , 06°32'N, 076°19'W, 1350-1450 m, 05 Dec. 1993 (fl bud), J. Pipoly et al. 17721 (MO) .

The identification key below is modified from Jaramillo-Vivanco and Balslev 2020. Except where specified otherwise, the information comes from Smith 1950 |, measurements of the digital image of the holotype ¶, or measurements of herbarium specimens#. The key was difficult to build, in part because of current limited access to physical specimens during the COVID-19 pandemic and in part because we were not able to identify obvious characters to separate species in some cases (e.g., between O. gordoniifolia and O. lehmannii ). This may mean that the key is difficult to use, but we have decided to include it in case it is of use to some.

Figures

Figure 4. Geographic distribution of Otoba scottmorii (black circle) and O. squamosa (black triangle). The shaded map area corresponds to the department of Antioquia.

Figure 7. Otoba squamosa A staminate flowering branch, with detail of malpighiaceous trichomes on abaxial leaf surface (detail below right) B detail of staminate inflorescence C staminate flower, with detail of trichomes D open staminate flower E longitudinal section of staminate flower and androecium F pistillate flowering branch G portion of pistillate inflorescence, showing the perianth (left) and ovary after the perianth has fallen H ovary I closed and open fruit (left), showing the pericarp and aril. Illustration by Bobbi Angell. A. Cogollo et al. 6279 (MO) (A-D), J. Pipoly et al. 17019 (MO) (E), J. Pipoly et al. 16798 (G), A. Cogollo et al. 6197 (MO) (F, H, E).

Figure 8. Otoba gordoniifolia A leaf on adaxial side B leaf on abaxial side, illustrating long petioles and vernation lines C staminate inflorescence D staminate flower E pistillate flowers, note the pubescent ovary F immature fruits. Photos by Rudy Gelis taken in Ecuador (unvouchered).