Gaylussacia itambensis G.O. Romão & V.C. Souza, 2025

Romão, Gerson Oliveira, Sampaio, Ariadne De Araújo, Oliveira, Reyjane Patrícia De & Souza, Vinicius Castro, 2025, A new species of Gaylussacia (Ericaceae) from the Espinhaço Range, southeastern Brazil, Phytotaxa 705 (3), pp. 269-278 : 270-274

Gaylussacia itambensis G.O. Romão & V.C. Souza , sp. nov.

Type:— BRAZIL. MINAS GERAIS. Santo Antônio do Itambé, summit of the Pico do Itambé , 2250 m elev., 10 February 1972 (fl., fr.), W.R. Anderson, M. Stieber, and J.H. Kirkbride Jr. 35778 (holotype UEC 30958 !, isotypes ESA 52260 !, L 246619 [ L.2593970 ]!, NY 994735 !, UB 1632 )

( Figure 2 ).

Diagnosis:— Gaylussacia itambensis is characterized by mature defoliated branches, with persistent cataphylls only on the axillary buds, and leaves with a distinctly revolute margin. This combination of characters is unique within this genus. Gaylussacia itambensis is similar to G. caparoensis Sleumer (1967: 362) by its mature defoliated branches and persistent cataphylls on the axillary buds but differs by its usually elliptic to suborbicular or usually obovate leaves with distinctly revolute margin.

Description:— Subshrub or shrub, 0.5–0.8 (–1.5) m tall; base erect, fastigiate or sub-corymbose top, highly branched. Whitish non-glandular trichomes and minute clavate-glands present on branches, leaves, rachis, bracts, flowers, and fruits; glandular-trichomes absent. Branches rugose, densely hirsutulous to setose, glabrescent, rarely with nigrescent clavate-glands, sparsely scattered; branchlets densely foliated, mature branchlets sparsely foliated or defoliated, cataphylls persistent, 1.0–1.5 (–2.0) mm long, deltoid, glabrous or margin ciliate, apex with nigrescent thick and elongated apical-gland. Leaves alternate or subopposite; petiole robust, 2–3 mm long, hirsute to setose similarly as on the abaxial surface; lamina broadly elliptic to suborbicular or broadly obovate, 0.8–2.3 × 0.5–1.3 cm, length to width ratio 1.36–2.83, coriaceous, slightly discolored, base obtuse to occasionally rounded or rarely acute, margin subcrenulate near apex, occasionally with dense conical glands between crenulations, nigrescent, distinctly revolute, apex rounded to obtuse, mucronulate, with apical gland thickly globose or subglobose, not recurved, adaxial surface lustrous, glabrous or sparsely pubescent at base of midvein, with clavate glands, nigrescent, glands sparsely scattered, abaxial surface sparsely to subdensely hirsute to setose on midvein, with clavate glands, nigrescent, sparsely scattered, venation brochidodromous, veins impressed on adaxial surface, prominent on abaxial surface. Racemes subapical axillary, 4–10-flowered; basal bracts reddish, broadly ovate, 1.5–3.0 mm long, margin ciliate, apex with elongate apical-gland; rachis 1.3–2.8 cm long, densely tomentellous to setose, with nigrescent sparsely scattered clavate-glands; floral bract 1, green or pinkish to reddish, obovate to oblanceolate, 4.0– 6.5 mm long, margin sparsely ciliate, occasionally with clavate-glands; bracteoles 2, inserted at apex or near the apex of pedicel, lanceolate to setiform, 2–4 mm long, margin ciliate and glandular similarly as on bracts. Flowers congested; pedicel 5–8 mm long, tomentellous to setose and glandular similarly to rachis; hypanthium reddish, densely tomentellous to setose, with subdensely scattered clavate-glands; calyx pinkish or reddish, 1.0– 1.5 mm long, usually tomentellous to setose at base, with sparsely scattered clavate-glands mainly at margins of lobes, lobes broadly triangular, sparsely ciliate; corolla pinkish, urceolate, 5.0– 6.5 mm long, sparsely setose at angles externally, glabrous internally, lobes recurved; stamens 4.5–5.0 mm long, filaments 0.5–1.0 mm long, subdensely setose, anther granulate, tubules 2.5–3.0 mm long; disc glabrous; style included or rarely exserted, 6–7 mm long, glabrous, stigma pateriform, granulate or undulate. Fruit depressed-globose, green or red when immature, black or blackish when mature, 3.0– 5.5 mm diameter, costate, subdensely tomentellous to setose.

Etymology:— The epithet itambensis refers to the locality Serra do Itambé, to which the species is restricted.

Notes:— This species was treated as Gaylussacia aff. caparoensis by Romão (2011) and hand-written annotations by Sleumer in 1973 (on the label of the holotype). Gaylussacia itambensis is similar to G. caparoensis by its mature defoliated branches and the persistent cataphylls only on the axillary buds, but differ in leaf shape, size and length to width ratio, margin, and geographical distribution ( Table 1 ).

Three sections are recognized in Gaylussacia ( Hooker 1876, Sleumer 1967). Gaylussacia itambensis belongs to Gaylussacia sect. Gaylussacia . This section is characterized by an evergreen habit, presence of glands and glandular trichomes, filaments shorter or of the same length as the anthers, and is disjunct distributed in North America ( United States of America, Canada to Saint-Pierre et Miquelon) and South America, being absent in Central America ( Hooker 1876, Sleumer 1967), differing to species in other sections ( Torrey & Gray 1843, Gray 1848, Koch 1872).

There are two endemic species of Gaylussacia to PEPI, viz. G. itambensis (present study) and G. setosa Kinoshita-Gouvêa (1981: 127) , which differ mainly in the indumentum and corolla coloration. While G. setosa has ferruginous glandular trichomes on the branches, leaves, flowers and fruits, and a white corolla, in G. itambensis the glandular trichomes are absent and the corolla is pinkish.

Habitat, Distribution and Phenology:— Gaylussacia itambensis is endemic to the Serra do Itambé (including areas outside the limits of the PEPI), Espinhaço Range, Minas Gerais state, southeastern Brazil at elevations of (1,367–) 2,038 –2,250 m a.s.l. ( Figure 3 ). The species occurs occasionally in campos rupestres and campo limpo vegetation interspersed with wooded areas around rock outcrops and galery forests, preferably in shrubby vegetation, with mossy ground cover in organic soil overlying sandy soil on sandstone rocks. The species was collected with flowers in February, April, and July, and with fruits in February, March, and July.

Conservation status:— The calculated Area of Occupancy (AOO) was 2 km ² and the Extent of Occurrence (EOO) was 13.679 km ². As such, the new species fits the IUCN Red List criteria B1ab+B2ab(i,ii,iv), being assessed as Critically Endangered (CR) ( IUCN 2022). In order to conserve the biodiversity of this site and adjacent areas, on January 21, 1998, Pico do Itambé State Park was created through Decree No. 39,398 of the State Government of Minas Gerais (SEMAD 2004). The Park is located in an area considered of special biological importance for biodiversity conservation in Minas Gerais state ( Drummond et al. 2005) and recognized by UNESCO as a “World Biosphere Reserve” ( Pereira et al. 2015). Although several new species of amphibians ( Barata et al. 2013), lycophyta ( Øllgaard 2012), and angiosperms have been discovered in the Pico do Itambé area ( Candolle 1828, Ravenna 1974, Kinoshita-Gouvêa 1981, Irwin & Barneby 1982, Kral & Wanderley 1988, Souza & Elias 2001, Rapini 2002, Atkins 2005, Versieux & Leme 2007, Van den Berg 2008, Louzada & Versieux 2010), revealing that it is a region of great plant endemism, integrating the biologically rich Serra do Espinhaço. The flora of the Park still remains poorly documented, with only a taxonomic treatment of Verbenaceae ( Cardoso et al. 2020) and a checklist for Bromeliaceae ( Versieux 2008) .

The area of Pico do Itambé has been occupied for centuries by dairy farmers, who take advantage of the suitable, natural fields for pasture. Fire is frequently used to clean and reinvigorate these fields, particularly during the dry season, and this seems to be the major conservation problem affecting areas adjacent to the park (SEMAD 2004).

Paratypes:— BRAZIL. MINAS GERAIS. Santo Antônio do Itambé: Parque Estadual do Pico do Itambé , Pico do Itambé , 18.39868° S 43.34816° W, 1367–2038 m a.s.l., 02 March 2009 (fr.), F. Almeda et al. 9669 ( CAS 410644 !, UEC 170418 !) ; Pico do Itambé : 18°24’ S 43°21’ W, 2050 m a.s.l., 05 April 1982 (fl.), A. Furlan et al. CFCR 3063 ( SPF 23270 !, UEC 101256 !); to 18 km of municipality, 17 July 1987 (fl., fr.), C. Kameyama et al. CFCR 11270 ( SPF 63948 !).

Figures

FIGURE 2. Gaylussacia itambensis. A. habit; B. stamens in frontal, lateral and dorsal view; C. calyx; D. longitudinal section of flower; E. fruit (from the holotype). Illustrated by Márcio Stefanelli Lara.

FIGURE 3. Map of the geographical distribution Gaylussacia itambensis. A. Brazil; B. Minas Gerais state with PEPI indicated; C. PEPI details with points of occurrence of G. itambensis.