Saranthe ustulata Petersen (1980: 165–166)

Funez, Luís Adriano, Hassemer, Gustavo & Trevisan, Rafael, 2016, Rediscovery, typification, and conservation assessment of Saranthe ustulata (Marantaceae), Phytotaxa 255 (1), pp. 91-98 : 92-96

Saranthe ustulata Petersen (1980: 165–166) , Fig. 1 .

Lectotype (designated here):—[illustration] Tab. XLVIII Fig. II in Petersen (1890).

Epitype (designated here):— BRAZIL. SANTA CATARINA: Apiúna : Ferrovia das Bromélias, 18 December 2014, L.A. Funez 3181 (epitype FURB 45758, Fig. 2 ; isoepitypes B, C, MBM) .

Description:—Plants 20–35 cm tall, short rhizome 1–6 cm long, 0.5 cm diameter, covered with cataphylls when young. Leaves homotropous,sheaths 7.3–17.0 cm long, apically short,sparsely covered by short trichomes, more dense adaxially and young leaves; petiole 0.1–15.6 cm long, pulvinus 0.5–1.4 cm, with a dense line of short trichomes adaxially, the rest glabrous; leaf blades narrowly oblong to elliptic, 7.3–15.4 × 3.2–6.4 cm, apically acute, abrupt acuminated, basally attenuate, glabrous in both faces. Terminal synflorescence 3–5 cm long, subtended by a non foliaceous bract 2.5–3.5 × 0.6–1.0 cm, lanceolate, apex with a pedicellate tuberculate black protuberance. Partial inflorescences 2–3, with 3–5 bracts each, deciduous or not, can be persistent in fruiting; rachis flexuous with well-marked scars; basic component of inflorescence with one pair of flowers; bracts ellipsoid 1.4–1.7 × 0.6–0.8 cm, glabrous, apically acute, papery to membranaceous, pale pinkish in vivo, stramineous in sicco, margins entire, subtending a brachyblastic cymule, internal bracts elliptic lanceolate 1.3 × 0.4 cm, membranous hyaline, apex acute. Flowers 1.0– 1.2 cm, whitish, sepals 3.1 × 0.2–0.3 cm, lanceolate, apically acute, glabrous; corolla tube ca. 2–3 mm, glabrous, corolla lobes 6–7 × 2–3 mm, oblong, apex rounded ended in a dark rough apiculus (in sicco), external staminodes 2, subequal, spatulate, ca. 6–7 × 3–4 mm; cucullate staminode 4 × 2 mm, with distal appendix lobed ca. 1 mm; callose staminode 6 × 3 mm, petaloid apex, bilobed, one lobe rounded and the other acute, callus laterally distal, stamen 3.5 mm with petaloid appendage ca. 2 × 1 mm, style ca. 3 mm, circinate, stigma funnel-shaped, apical portion with pollen plate. Ovary dense pilose, 2.0 × 1.5 mm, fruit capsule 7–12 × 3–4 mm, pilose.

Distribution:—This species is endemic to the Atlantic rainforest in Apiúna municipality, eastern Santa Caterina, southern Brazil ( Fig. 3 ). The no longer extant holotype, a collection by J.F.T. Müller, is recorded from Blumenau municipality; however, Blumenau used to include a much larger area during the nineteenth century ( IBGE 2014), including what is Apiúna municipality today. Therefore, it is probable that Müller’s plants were also collected in Apiúna.

Habitat:— Saranthe ustulata inhabits the understory of forests and trail edges ( Figure 1 ), and although restricted to a single location, it is locally abundant.

Conservation Status:—Critically endangered (CR—B2a,b[iii]). The area of occupancy (AoO) of this species is less than 10 km 2 and only one population is known. In addition, the intense deforestation in this region is usually followed by plantations of Pinus spp. and Eucalyptus spp. , which, besides the habitat occupation, also degrades the quality of adjacent forest. Future threats such as the construction of a hydroelectric plant, which is already planned, would also most certainly bring this species to extinction.

Phenology: —Flowering from October to December; fruiting from November to February.

Notes:— Saranthe ustulata was described by Petersen (1890), based on material collected by Johann Friedrich Theodor Müller during the nineteenth century around Blumenau municipality (southern Brazil). The author cited in the protologue also one illustration “ Tabula nostra XLVIII Fig. II”, that is consequently original material for the name (art. 9.3 of the ICN, McNeill et al. 2012). We searched for the original material in B, G, K, NY and R herbaria, where the plants collected by Johann F.T. Müller are known to have been deposited ( Vegter 1976), but we were not able to trace any cited or uncited specimens belonging to the original material. Accordingly, we designate the illustration in Petersen (1890, Tab. XLVIII Fig. II) as the lectotype of the name S. ustulata (art. 9.12 of the ICN). Considering that the selected lectotype could be ambiguos, it seems appropriate to select an interpretative type (epitype, art. 9.8 of the ICN, McNeill et al. 2012) in order to preserve the correct application of the name. The specimen selected as epitype ( Figure 2 ), collected by L.A. Funez in Ferrovia das Bromélias (Apiúna, Santa Catarina, Brazil), is housed in FURB herbarium, and duplicates are in B, C and MBM.

Few individuals were observed in reproductive stage or had old inflorescences. After flowering, most of infrutescences bend toward the soil, some being completely under litter. There are no evidences that the plant buries the fruits, yet the burial caused by leached litter and soil is plausible. This can prevent or reduce predation of fruits and seeds, but restricts dispersion, what could explain a restrict distribution ( Krapovickas & Gregory 1994). Although incipient, the knowledge about seed dispersal in Marantaceae suggests that most are disperse by birds or ants ( Horvitz & Corff 1993, Anderson 1998). Characteristics of Saranthe ustulata , like small, colorless fruits and presence of a pale oil rich aril in the seeds, points to a myrmecochorous syndrome, with a dispersal distance of few centimeters to about 10 meters, depending on the ant species ( Horvitz 1981, Horvitz & Corff 1993). According to Horvitz & Corff (1993), the species of Marantaceae dispersed by ants tend to form denser clusters than those dispersed by birds, confirming our observations in the field.

Despite of the well documented flora of “Vale do Itajaí” ( Gasper et al. 2014) and the proximity to an extensive conservation unit, the “Parque Nacional da Serra do Itajaí” (PNSI), which had the herbaceous species recently surveyed ( Funez & Gasper 2014), this species had never been collected. In addition to Saranthe ustulata , the region between the middle and high “Itajaí Valley” is the habitat of many rare and endemic species, as Dyckia ibiramensis Reitz (1962: 104–106) , Myrceugenia hamoniana ( Mattos 1963: 1–2) Sobral (2010: 53–54) , Nothoscordum ibiramense Ravenna (1990: 5) , Raulinoa echinata Cowan (1960: 90–91) and Solanum matadori Smith & Downs (1964: 432) ( Hassemer et al. 2015). We thus reinforce the critical importance of protecting the remaining forest fragments in this area in order to protect these critically endangered species, and also many still undescribed.

Key to the species of Saranthe in the South region of Brazil (largely based on Vieira et al. 2012)

1. Axillary inflorescence, bracts pilose or glabrous, apically acute with ciliate margins ....................................................... S. eichleri

- Terminal inflorescence, bracts glabrous or pilose only in basal portion, apically acute or rounded, with hyaline margins..............2

2. Plants 70–130 cm tall, bracts apically rounded, partial inflorescence with 14–22 bracts, petiole 30–43 cm long..... S. leptostachya

- Plants 25–30 cm tall, bracts apically acute, partial inflorescence with 3–5 bracts, petiole 0.1–15.6 cm long.................... S. ustulata

Figures

FIGURE 1. Saranthe ustulata. A. Inflorescence and flower in lateral view; B. Bracts and flower in frontal view; C. Synflorescence at plant basis; D. Habit.

FIGURE 2. Image of the epitype of Saranthe ustulata (FURB 45758).

FIGURE 3. Location of the known population of Saranthe ustulata, in Santa Catarina, Brazil.