Sinningia hoehnei Chautems, A.P. Fontana & Rossini, 2019

Chautems, Alain, Valquíria F. Dutra,, Fontana, André P., Peixoto, Mauro, Perret, Mathieu & Rossini, Josiene, 2019, Three new species of Sinningia (Gesneriaceae) endemic to Espírito Santo, Brazil, Candollea 74 (1), pp. 33-42 : 37-39

Sinningia hoehnei Chautems, A.P. Fontana & Rossini , spec. nova

( Fig. 2 B–C, 4).

Holotypus: BRAZIL. Espírito Santo: Castelo , [20°32'34"S 41°16'42"W], 29.V.2012, fl., A.P. Fontana & R.P. Fontana 7421 ( MBML-48993 !; iso-: CEPEC, G [ G00426964 ]!, K, NY [ NY01404566 ] image seen, RB-631055 image seen, SPF) .

Flowers of this species resemble those of Sinningia barbata (Nees & Mart.) G. Nicholson , but differ by ovate leaf blade (vs elliptic-obovate), pedicel 1,5– 3 cm long (vs 5–8 cm long), corolla laterally and ventrally inflated for most of its length (vs corolla with the basal portion tubular and strongly bent downward and then ventrally inflated), slightly constricted at mouth (vs noticeably constricted), throat yellow with vinaceous streaks (vs plain white or cream, rarely with vinaceous dotted lines), pubescent outside (vs hirsute).

Herb rupicolous or terrestrial, arising from perennial tuber, 1– 2 × 1– 3 cm in diam. Stems erect, 25–40 cm tall, usually unbranched, green, glabrescent, internodes 3– 6 cm long. Leaves 4–8 pairs, decussate, isophyllous, petiole 1.5–5.5 cm long, green, slightly vinaceous at the apex, puberulous, blade ovate 4,5–10 × 2.1–6 cm, light green adaxially, sparsely pubescent with uni- and multicellular trichomes, pale green abaxially, glabrescent, base obtuse, apex acute, margin crenate-denticulate, 5–8 pairs of veins. Inflorescence a frondose florescence with cymes reduced to 1 flower in the axils of the 2–3 large and upper leaf pairs. Flowers borne on erect pedicels, 1.5–3.2 cm long, light green, puberulous. Calyx campanulate, fused at base for 3–4 mm, 1.4–2.3 × 0.7–1.3 cm, broadly ovate, subcordate at base and forming a wing at their junction, acuminate at the apex, green, puberulous abaxially, glabrous adaxially. Corolla obliquely inserted in the calyx , tubular-campanulate, ventricose, 3.2–4 cm long, outside white and finely pubescent, tube at the very base forming a nectary chamber, c. 7 mm diam., then, briefly constricted to around 5 mm in diam., widening ventrally and laterally to about 2 cm at the widest section, around the middle, dorsally forming 2 longitudinal grooves, throat yellow with fine vinaceous streaks ventrally, ventral lobe pale purple, lateral lobes purplish around the base. Stamens 4, included, filaments 1.4–1.7 cm long, white, puberulous, anthers coherent by their apex and side, forming a rectangle, pollen white; nectary formed by five separate glands, c. 1 mm long; ovary conical, whitish, puberulous, style inserted, up to 1.5–1.7 cm long, white, puberulous, stigma stomatomorphic. Fruit a semi-fleshy capsule, 1.3–1.6 cm long, greenish outside, dehiscent, the two valves opening 180° at maturity, cream inside, seeds fusiform to prolate, dark brown.

Etymology. – The name refers to the Brazilian botanist F.C. Hoehne (1882–1959) who dedicated part of his career to the study of Brazilian Gesneriaceae . An illustration of the species, misidentified as Sinningia barbata , was published as table 238 in his Iconografia das Gesneriáceae do Brasil (HOEHNE, 1970). This book was organized and published after Hoehnes’s death by A.R & C.B. Teixeira, based on notes and documents left at the “Instituto de Botânica” in São Paulo.

Distribution and ecology. – The species was found in a unique locality in the southern part of the state of Espírito Santo, on the side of the road ES- 379 in a stretch connecting the cities of Castelo and Muniz Freire. Sinningia hoehnei was recorded in a fragment of Seasonal Semi-deciduous Forest at around 330 m above sea level ( Fig. 1 ). Plants were observed in a population of less than 50 individuals that did not exceed 5 m ² of occupation area. They were growing as saxicolous, living on a thin layer of organic matter, among herbs like Commelina sp., Pitcairnia flammea Lindl. , under trees, with the most frequent species being Tabernaemontana hystrix Steud. , Ramisia brasiliensis Oliv. , Gallesia integrifolia (Spreng.) Harms and Anadenanthera colubrina var. cebil (Griseb.) Altschul.

Phenology. – Flowers were observed in May and also in November-December (in cultivation). Fruits were registered reaching maturity in May and February (in cultivation).

Conservation status. – The new species has been observed and collected in a single locality, i.e. EOO <100 km ², and AAO <10 km ² along an unpaved road. Projects of improving and paving this section of road ES-379 were scheduled in 2014. Nevertheless, those projects seem so far paralyzed. Therefore, the locality remains strongly at risk of being destroyed. Sinningia hoehnei is assigned a preliminary assessment as “Critically Endangered” [CR B2ab(iii)] using the IUCN Red List ( IUCN, 2012).

Notes. – Clearly, this species is morphologically related to S. barbata , which was confirmed by preliminary phylogenetic analysis (M. Perret, unpubl. data). We present in Table 1 the main morphological differences between S. hoehnei and S. barbata .

Material of this species was introduced in cultivation under the provisional name Sinningia sp. “Castelo”.

Paratypi. – BRAZIL. Espírito Santo: Castelo, Rodovia ES-379, 29.V.2013, fl., L. Kollmann & A.P. Fontana 12720 ( MBML-46244 ); Alegre , Reeve [Rive], 9.XII.1924, J. Vidal 72 ( R-2094 ) .

Figures

Fig. 2. – Photographs of Sinningia Nees. A. Sinningia flammea Chautems & Rossini; B–C. Sinningia hoehnei Chautems, A.P. Fontana & Rossini; D. Sinningia stapelioides Chautems & M. Peixoto. [Pictures: A–C: A. P. Fontana; D: M. Peixoto]

Fig. 1. – Distribution map of Sinningia flammea Chautems & Rossini (triangles), S. hoehnei Chautems, A.P. Fontana & Rossini (squares) and S. stapelioides Chautems & M. Peixoto (star).