Rinorea cogolloi Hoyos-Gómez, 2024

Hoyos-Gómez, Saúl E., Callejas Posada, Ricardo & Wahlert, Gregory A., 2024, Seven new species of Rinorea (Violaceae) from the Neotropics, PhytoKeys 242, pp. 241-271 : 241-271

5. Rinorea cogolloi Hoyos-Gómez sp. nov.

Type.

Colombia. Dept. Antioquia: Mpio. de San Luis, Cañón del Río Claro , sector norte, margen izquierda, 5 ° 53 ' N, 74 ° 39 ' W, 340–500 m elev., 24 Dec 1983, A. Cogollo 1075 (holotype: HUA [ 032011 ]!; isotypes: COL [ 299700 ]!, MO [acc. 3737288 ; barcode MO- 1590440 ]!) .

Description.

Rinorea cogolloi is similar to R. hirsuta by the elliptic lamina with ferruginous trichomes and lacking domatia, but it differs by the asymmetrical lamina base (vs. lamina base symmetrical in R. hirsuta ), inflorescence thyrsoid (vs. inflorescence racemose), petals 2–3 × 0.7–1.3 mm (vs. 4–4.3 × 1.5–1.8 mm), stamens 1.7–2 mm long (vs. 3–3.3 mm long), dorsal gland pubescent (vs. dorsal gland glabrous), seeds pubescent (vs. glabrous) and capsule asymmetrical and pilose (vs. capsule symmetrical and velutinous).

Shrubs or trees 2–6 m tall, terminal branchlets pubescent with erect ferruginous trichomes 0.4–0.6 mm long. Leaves opposite, petiolate; petiole 1.9–5 mm, pubescent with erect ferruginous trichomes 0.3–0.4 mm long; stipules deciduous, free, lanceolate, membranous, 1.9–2.5 × 0.7–1 mm, pubescent with appressed ferruginous trichomes 0.2–0.3 mm long, margin ciliolate; lamina elliptic, 7–17 × 2.5–7 cm long, herbaceous, adaxially pubescent on mid-vein with erect ferruginous trichomes 0.2–0.3 mm long, abaxially pubescent with erect ferruginous trichomes 0.4–0.5 mm long, with 5–8 major secondary vein pairs, semi-craspedodromous, secondary veins with regular spacing and angled to the mid-vein, base rounded, asymmetrical, margin crenate, apex acuminate, acumen 0.5–1 cm long, mucronate, leaf domatia absent. Inflorescence axillary, lateral or terminal, thrysoid, 4–8 cm long, 0.5–1 cm diam., axis pubescent with erect ferruginous trichomes 0.2–0.3 mm long; cymules 3–5 flowered; common peduncule 1–1.5 mm, pubescent with erect ferruginous trichomes 0.2 mm long; pedicels 0.5–1 mm, articulated at the base, pubescent with erect ferruginous trichomes 0.2 mm long; bractlets alternate, persistent below articulation, ca. 0.5 × 0.5 mm, herbaceous, costa pubescent with appressed ferruginous trichomes 0.2 mm long, margin ciliolate; peduncle bracts persistent, broadly triangular, 1–1.5 × 1–1.5 mm, herbaceous, costa pubescent with appressed ferruginous trichomes 0.3–0.4 mm long; margin ciliolate. Flowers 2.5–2.8 × 2.5–2.8 mm, sepals subequal in size and shape, triangular, 1–1.5 × 0.5–0.7 mm, pubescent with appressed ferruginous trichomes 0.2 mm long, margin ciliolate; petals elliptic, 2–3 × 0.7–1.3 mm long, pubescent with appressed ferruginous trichomes 0.2 mm long, margin ciliolate, cream to yellow in vivo, brown when dry; stamens 1.7–2 mm long, filaments free, glabrous, 0.9–1 mm, dorsal gland covering the filament, pubescent with spreading ferruginous trichomes 0.2 mm long; anthers elliptic, 0.6–1 × 0.4–0.6 mm, pubescent with spreading ferruginous trichomes 0.2 mm long, apex obtuse, connective 0.6–0.7 mm, pubescent with appressed ferruginous trichomes 0.2 mm long, dorsal connective scale lanceolate, 1.2–1.6 × 0.7–0.9 mm, scarious, margin subentire, orange-brown; ovary globose, 1–1.5 mm diam., pubescent with erect ferruginous trichomes 0.3–0.5 mm long; style erect subclavate, filiform, 1.5–1.8 × 0.1 mm, stigma acute. Fruit an asymmetrical, subligneous capsule dehiscent along three sutures, ellipsoid, 0.8–1.5 × 0.5–0.6 cm, apex acuminate, veined, pubescent with erect ferruginous trichomes 0.2–0.3 mm long, green when fresh, brown when dry. Seeds one per valve, globose, 5–7 mm diam., with maculae, pubescent with erect ferruginous trichomes 0.3 mm long, brown when dry. (Fig. 8 )

Distribution and habitat.

Rinorea cogolloi is narrowly distributed in Antioquia Department, Colombia, an area that coincides with the Biogeographical Province of Magdalena in the Pacific Dominion (sensu Morrone 2014). The species grows in lowland tropical rainforests in a region characterised by a karstic topography, occurring at elevations of 30– 500 m. (Fig. 9 )

Etymology.

Rinorea cogolloi is named in honour of Professor Alvaro Cogollo who has made contributions to the knowledge of Magnoliaceae taxonomy and the flora of Colombia, especially the middle Magdalena River Valley, where the species is endemic.

Phenology.

The species flowers between August and December; fruiting specimens were collected in February and August through October.

Conservation status.

Rinorea cogolloi has a geographic range in the form of an EOO of 1,641 km 2 and AOO of 32 km 2. It is currently known from eight locations outside of protected areas. The region, underlain by karstic rocks, is heavily impacted by limestone extraction for concrete production and uncontrolled deforestation for grazing, agriculture and logging. Another location in north-eastern Antioquia Department is threatened with gold mining and deforestation. Given the high demand for cement products, the generally poor management of forest resources in the area and the number of locations, we project a continuing decline in the extent and quality of habitat for the species. Rinorea cogolloi is preliminarily assigned to the “ Vulnerable ” category [ VU B 1 + B 2 ab (iii)] in accordance with the IUCN Red List Categories and Criteria ( IUCN 2012).

Notes.

Hekking (1988) noted the aberrant lamina pubescence of several specimens of Rinorea lindeniana (e. g. A. Cogollo 786, 1075, 1483). Rinorea cogolloi and R. lindeniana share several characteristics, such as leaf venation architecture and asymmetrical lamina bases, but R. cogolloi is readily separated from R. lindeniana by the densely pubescent indument on the abaxial lamina surface (vs. the abaxial lamina surface pilose to glabrescent in R. lindeniana ). Rinorea cogolloi occurs sympatrically with R. galeanoae-bernalii (see below), but R. cogolloi has densely pubescent indument on the abaxial lamina surface (vs. abaxial lamina surface glabrescent in R. galeanoae-bernalii ), pubescent fruit with spreading, erect ferruginous trichomes 0.3–0.4 mm long (vs. densely tomentose fruit) and the seeds pubescent with erect ferruginous trichomes 0.3 mm long (vs. seeds glabrous). Rinorea cogolloi and R. hirsuta have been confused by the similarity of the leaves and indumenta, but they can be differentiated by the asymmetrical lamina base, thyrsoid inflorescence, dorsal gland pubescent, pubescent seeds and capsule asymmetrical and pilose. In addition, these two species have different distributions, with R. cogolloi occurring in the Magdalena Province and R. hirsuta restricted to the Chocó-Darien Province (sensu Morrone (2014)). Rinorea cogolloi is also similar to R. pubiflora var. pubiflora , but it can be differentiated by its valves containing one seed (vs. valves containing three seeds in R. pubiflora ) and the thyrsoid inflorescence (vs. racemose inflorescence). Table 2 highlights the key morphological differences amongst these five species.

Additional specimens examined.

Colombia. Dept. Antioquia. Mpio. de Caucasia: Vda. la Arenosa , km 45 vía al Bagre , Finca la Natalia , 7 ° 47 ' 46 " N, 74 ° 53 ' 9 " W, 70–100 m elev., 26 Aug 2022 (st), S. E. Hoyos-Gómez et al. 5184 ( HUA, UBDC) ; ibid., 7 ° 47 ' 59 " N, 74 ° 52 ' 45 " W, 80 m elev., 10 Nov 2022 (fr), M. Montoya M 9004 ( HUA) ; Mpio. de Nechí: Vda. El Catorce, entre la mina el 14 y la roca del camino , 8 ° 94 ' 60 " N, 74 ° 46 ' 14 " W, 30–40 m elev., 6 Mar 2010 (fl), W. Rodríguez 6599 ( COL, MEDEL) ; Mpio. de Puerto Triunfo: alrededores de la Gruta “ El Condor , ” 5 ° 56 ' N, 74 ° 50 ' W, 12 Oct 1983 (fl, fr), A. Cogollo 786 ( COL, HUA, MO) ; ibid., 22 Oct 1989 (fr), J. G. Ramírez 4263 ( JAUM) ; Río Claro carretera al Cairo , 17 Sep 1982 (fl, fr), E. Rentería 2722 ( JAUM, MO) . Mpio. de Sonsón: vereda Jerusalén , 5 ° 55 ' 00 " N, 74 ° 51 ' 00 " W, 200 m elev., 24 Dec 2010 (st), S. E. Hoyos-Gómez et al. 1145 ( HUA, JAUM, MO) ; ibid., 5 ° 55 ' 00 " N, 74 ° 51 ' 00 " W, 200 m elev., 24 Dec 2010 (fl), S. E. Hoyos-Gómez et al. 1152 ( HUA, JAUM) ; ibid., 5 ° 55 ' 00 " N, 74 ° 51 ' 00 " W, 200 m elev., 24 Dec 2019 (fl), S. E. Hoyos-Gómez & G. A. Wahlert 3780 ( HUA, JAUM) ; ibid., 5 ° 53 ' 30 " N, 74 ° 50 ' 58 " W, 200 m elev., 23 Sep 2018 (fl, fr), J. P. Tobón et al. 2798 ( HUA, JAUM) ; vereda Jerusalén , 5 ° 53 ' 30 " N, 74 ° 50 ' 58 " W, 380 m elev., 23 Sep 2018 (fr), J. P. Tobón et al. 2799 ( HUA, JAUM) ; ibid., 5 ° 53 ' 39 " N, 74 ° 51 ' 08 " W, 380 m elev., 24 Sep 2018 (fl, fr), J. P. Tobón et al. 2803 ( HUA, JAUM) ; ibid., 5 ° 53 ' 25 " N, 74 ° 50 ' 50 " W, 24 Sep 2018 (fl, fr), J. P. Tobón et al. 2806 ( HUA, JAUM) ; ibid., 5 ° 53 ' 44.1 " N, 74 ° 51 ' 18 " W, 1 Feb 2019 (fr), J. P. Tobón et al. 2897 ( JAUM) ; vereda Jerusalén, Reserva Natural Cañón del Río Claro, “ El Refugio ”, margen derecha, 5 ° 53.759 ' N, 74 ° 51.219 ' W, Apr 2013 (fr), L. Cano et al. 43 ( HUA) ; corregimiento Jerusalén, vía Medellín-Bogotá, predios de Sumicol , cuenca del Río Claro , en cercanías de la torre de energía T 66 , 5.915756 ° N, 74.849186 ° W, 4 Aug 2020 (fl, fr). J. M. Velez et al. 7388 ( MEDEL, COL) ; ibid., 5.916104 ° N, 74.849473 ° W, 17 Sep 2020 (fl), J. M. Velez et al. 7511 ( JAUM) ; ibid., 5.916182 ° N, 74.850481 ° W, 16 Feb 2021 (fr). J. M. Velez et al. 7604 ( JAUM) .

Figures

Figure 8. Rinorea cogolloi Hoyos-Gómez A habit B detail of leaf pubescent, abaxial surface C leaf architecture D infructescence E cymule with flowers F sepals, abaxial surface G petals, abaxial surface H stamens, showing adaxial and abaxial surfaces I gynoecium J infructescence K detail of fruit showing one seed per valve L seed. (A – L: A. Cogollo 786 [MO]).

Figure 9. Distribution of Rinorea cogolloi (squares), R. galeanoae-bernalii (bolts), R. hirsuta (triangles).