Rinorea callejasii 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

1. Rinorea callejasii Hoyos-Gómez sp. nov.

Type.

Panamá. Prov. Colón: forested slopes of Cerro El Jefe , near large coffee finca, 9 ° 14 ' 02 " N, 79 ° 22 ' 30 " W, 700–1000 m elev., 24 Jan 1970, R. L. Wilbur et al. 11327 (holotype: MO [acc. 2027894 ; barcode MO- 554811 ]!; isotypes: F [cat. 1694605 ]!, GH!, NY [barcode 04112199 ]!, US [cat. 2640360 ; barcode 03009254 ]!) .

Description.

Rinorea callejasii is most similar to R. pubiflora var. pubiflora s. s. by the lamina with symmetrical bases and bearing domatia, filaments free and fruit symmetrical, but it differs by the branchlets densely pubescent with ferruginous trichomes (vs. branchlets glabrescent in R. pubiflora var. pubiflora s. s.), primary and secondary veins on the abaxial lamina surface densely villous with ferruginous trichomes (vs. primary and secondary veins on the abaxial lamina surface glabrescent), fruit 1.5–2 cm long with 2 ovules per carpel (vs. fruit 2–3.5 cm long with 3 ovules per carpel) and the seeds glabrous (vs. seeds pubescent).

Shrubs or trees 2–12 m tall, terminal branchlets pubescent with erect ferruginous trichomes 0.4–0.5 mm long. Leaves opposite, petiolate; petioles 2–10 mm long, pubescent with erect ferruginous trichomes 0.2–0.3 mm long; stipules deciduous, free, elliptic, 1.6–4.8 × 0.8–1.3 mm, pubescent with appressed ferruginous trichomes 0.5 mm long; lamina elliptic, 4.6–15 × 2–6.5 cm, adaxial surface pilose on the mid-vein and secondary veins with erect ferruginous trichomes 0.4–0.5 mm long, abaxially pubescent on the mid-vein, trichomes on the secondary and tertiary veins, trichomes 0.3–0.5 mm long, erect, ferruginous, base cuneate, symmetrical, margin subserrate, apex acuminate, acumen 0.7–1.2 cm long, mucronate; with 8–10 major secondary vein pairs, major secondary veins eucamptodromous becoming brochidodromous distally, with regular spacing and uniform angle of the major secondary vein; major secondary attachment to mid-vein decurrent, leaf domatia present. Inflorescence axillary, terminal or subterminal, racemose, 3–5 cm long, 0.7–1.5 cm diam., axis pubescent with erect ferruginous trichomes 0.3–0.5 mm long; pedicels 1.8–3.6 mm long, pubescent with erect golden trichomes 0.3–0.5 mm long, articulated near the base; peduncle bracts deciduous, narrowly triangular, 1.5–1.8 × 1.5–1.8 mm, herbaceous, pubescent along the costa with appressed golden trichomes 0.3–0.5 mm long, margin ciliolate; bractlets persistent below articulation, subopposite, 1 × 1 mm. Flowers 3–3.6 × 3–3.4 mm; sepals subequal, triangular, 1.3–2 × 1.4–1.6 mm, 5 - to 9 - veined, pubescent along the costa with appressed golden trichomes 0.3 mm long, margin ciliolate, apex apiculate; petals lanceolate, 3.4–3.8 × 0.7–1.4 mm, pubescent along the costa with appressed golden trichomes 0.3–0.4 mm long, margin entire, apex acute, white; stamens 2.9–3.3 mm long, all filaments free, dorsal gland pilose with spreading golden trichomes 0.2–0.3 mm long covering lower half of the filament, anthers elliptic, 1.1–1.4 × 0.3–0.5 mm, apex rounded, connective 0.7–0.8 mm long, dorsal connective scale conspicuous, lateral as well as apical, lanceolate, 2.2–2.5 × 0.8–1 mm, margin entire, orange-brown; ovary globose, 0.8–1 × 0.9–1 mm, pubescent with erect, golden trichomes 0.4–0.5 mm long; style erect, filiform, 2–2.3 × ca. 0.1 mm, pubescent proximally with appressed golden trichomes 0.2–0.3 mm long, stigma undifferentiated. Fruit a symmetrical, subligneous capsule dehiscent along three sutures, ellipsoid, 1.5–2 × 0.5–0.6 cm, apex acuminate, pubescent with erect golden trichomes 0.2–0.3 mm long, green in vivo, brown when dry. Seeds two per valve, globose, 4–5 mm diam., glabrous, with maculae, brown when dry. (Fig. 1 )

Distribution and habitat.

Rinorea callejasii is restricted to the Caribbean coast of Colón and San Blas Provinces, Panama and the Pacific coast of Chocó Department, Colombia, a region belonging to the biogeographic Province of Chocó-Darien in the Pacific Dominion (sensu Morrone (2014)). It occurs in lowland humid rainforests at elevations of 30– 500 m. (Fig. 2 )

Etymology.

Rinorea callejasii honours Dr. Ricardo Callejas Posada, Professor of Biology at Universidad de Antioquia, Medellín, Colombia. Prof. Callejas has made many contributions to the taxonomic knowledge of the Piperaceae and expanded the understanding of the diverse flora of Colombia, especially in the Department of Antioquia. He was the major advisor of SEHG.

Phenology.

The species flowers January through March; specimens in fruit were collected in March and May.

Conservation status.

Rinorea callejasii has a geographic range in the form of an EOO of 40,729 km 2 and AOO of 52 km 2. In Panama, it is represented by two locations within Chagres National Park and one location in Soberanía National Park. Outside of the protected areas, where the species exists at nine locations, it is threatened by the exploitation of natural resources, mineral extraction and energy development. In Colombia, it is represented by two locations, both outside protected areas. The species does not meet the criteria necessary to assign a threatened status. However, given ongoing habitat disturbance, it is likely that the species will qualify in the near future for a threatened status and, thus, it is preliminarily assessed with a status of “ Near Threatened ” ( NT).

Notes.

Rinorea pubiflora , as circumscribed by Hekking (1988), was morphologically variable across its large distribution in the Neotropics. He recognised a variety of R. pubiflora : var. grandifolia (Eichler) Hekking , which was further divided into two forms: f. grandifolia and f. andersonii (Sandwith ex Hekking) Hekking. Rinorea callejasii is a segregate of R. pubiflora var. pubiflora s. s. In attempting to explain the morphologically divergent specimens of var. pubiflora from Panama (e. g. G. C. de Nevers et al. 5075), Hekking (1988) invoked a scenario of hybridisation between R. squamata S. F. Blake and var. pubiflora. However, our analysis of morphological divergence and biogeographic distribution suggest that R. callejasii is a separately evolving lineage from the nominate species (sensu De Queiroz (2008)) and deserving of recognition as a new taxon at the rank of species.

Rinorea callejasii is sympatric with four other taxa of Rinorea . Rinorea squamata and R. hirsuta Hekking can be differentiated by their single glabrous seed per valve (vs. two glabrous seeds per valve in R. callejasii ). Rinorea dasyadena is distinguished by its two pubescent seeds per valve and asymmetrical lamina base (vs. two glabrous seeds and symmetrical lamina base). Rinorea lindeniana var. fernandeziana can be separated by its one pubescent seed per valve (vs. two glabrous seeds per valve).

Additional specimens examined.

Colombia. Dept. Chocó. Mpio. de San José del Palmar: Hoya del río San Juan , 04 ° 36 ' N, 76 ° 54 ' W, 7 Apr 1979 (fr), E. Forero et al. 4780 ( COL, MO, US) ; Mpio. Bahía Solano: hills behind Bahía Solano , 6 ° 13 ' 14 " N, 77 ° 24 ' 27 " W, 0–250 m elev., 5 Jan 1973 (fl), A. H. Gentry & E. Forero 7245 ( COL, F, MO, U) . Panamá. Prov. Colón: Santa Rita Ridge lumber road , 23 Feb 1968 (fl), M. D. Correa-A. & R. L. Dressler 765 ( MO, NY, US) ; Santa Rita Ridge, 9 ° 19 ' N, 79 ° 39 ' W – 9 ° 24 ' N, 79 ° 48 ' W, 1 Mar 1971 (fl), T. B. Croat 13831 ( MO) ; El Llano-Cartí Road, 10 miles from Inter-American Highway near El Llano , 9 ° 17 ' 45 " N, 78 ° 56 ' 15 " W, 330 m elev., 28 Mar 1976 (fl, fr), T. B. Croat 33754 ( COL, MO) ; El Llano-Cartí Road, 5–6 miles N of Inter-American Highway at El Llano , 09 ° 15 ' 30 " N, 78 ° 55 ' 50 " W, 350–375 m elev., 7 May 1976 (fl), T. B. Croat 34788 ( COL, MO) ; El Llano-Cartí Road, km 26.5, trail NE from road , [coordinates on original label: 9 ° 19 ' N, 78 ° 55 ' W; corrected to 9 ° 22 ' N, 78 ° 58 ' W], 175 m elev., 9 Mar 1985 (fl), G. C. de Nevers et al. 5075 ( MBM, MO) ; Santa Rita Ridge road, 4 miles from Transisthmian Highway to Agua Clara weather station , 9 ° 21 ' N, 79 ° 42 ' W, 11 Dec 1973 (fl), R. L. Dressler et al. 8846 ( MO) ; Santa Rita Ridge road, 4 miles from Transisthmian Highway to Agua Clara weather station , 9 ° 21 ' N, 79 ° 42 ' W, 500 m elev., 11 Dec 1973 (fl), A. H. Gentry et al. 8846 ( MO, COL) ; along road into Santa Rita, E of Agua Clara , 9 ° 07 ' 10 " N, 79 ° 42 ' 02 " W, 4 Mar 1973 (fl), H. Kennedy 2741 ( MO) ; Santa Rita Ridge , 9 ° 20 ' N, 79 ° 45 ' W, 13 May 1986 (fl), G. D. McPherson 9168 ( MG, MO) ; 12.7 km from Inter-American Highway , 350 m elev., 15 Feb 1975 (fr), S. A. Mori 4694 ( COL) ; Santa Rita Ridge Road , 17 km from Boyd-Roosevelt Hwy , 9 ° 22 ' N, 79 ° 40 ' W, 450 m elev., 14 Mar 1975 (fl), S. A. Mori et al. 5041 ( COL, MO) ; El Llano-Cartí Road, 20.7 km north from Inter-American Hwy , 9 ° 17 ' 58 " N, 78 ° 55 ' 58 " W, 20 Mar 1975, S. A. Mori & J. A. Kallunki 5115 ( COL, MO) ; 9 km from Inter-American Highway, 9 ° 15 ' 50 " N, 78 ° 55 ' 51 " W, 350 m eelv, 22 Mar 1975 (fr), S. A. Mori 5154 ( COL, MO) ; upper Río Piedras headwaters, along trail from end to Santa Rita Ridge road, ca. 11 km SW of Cerro Braja , 9 ° 25 ' N, 79 ° 35 ' W, 4 May 1981 (fr), K. J. Sytsma et al. 4311 ( MO) . Prov. San Blas: El Llano-Cartí Road, 7 miles on Interamerican Highway , 9 ° 15 ' N, 79 ° 00 ' W, 550 m elev., 14 Mar 1985 (fr), G. D. McPherson 6851 ( MO) .

Figures

Figure 1. Rinorea callejasii Hoyos-Gómez A habit B detail of young twig with pubescence C detail leaf showing domatia, abaxial surface D leaf architecture E inflorescence F flower G sepals, abaxial surface H petals, abaxial surface I stamens, adaxial surface J gynoecium K infructescence L fruit, showing two seeds per valve M seed. (A – J: M. D. Correa 765 [MO]; K – M: G. D. McPherson 6851 [MO]).

Figure 2. Distribution of R. pubiflora f. grandifolia (triangles), R. pubiflora var. pubiflora (pentagons), R. pubiflora f. andersonii (stars), Rinorea callejasii (asterisks).