Keraunea bullata Moonlight & D.B.O.S.Cardoso, 2023

Moonlight, Peter W. & Cardoso, Domingos Benicio Oliveira Silva, 2023, A taxonomic revision of Keraunea, including three new species and its phylogenetic realignment with Ehretiaceae (Boraginales), PhytoKeys 219, pp. 145-170 : 145

2. Keraunea bullata Moonlight & D.B.O.S.Cardoso sp. nov.

Fig. 4

Diagnosis.

Most similar to K. confusa with relatively broad leaves with brochidodromous venation but differing from it in smaller leaves (reaching 10 × 7.4 cm versus 18 × 12 cm) with a bullate texture (versus rugose) and by its tertiary veins, which are raised from the lower leaf surface (versus not raised).

Type.

Brazil. Bahia: Mun. Jequié, Bairro Suica , 13°51'S, 40°5'W, M.L. Guedes, D.M. Loureiro & D.L. Santana 9176 (holotype: ALCB [acc. #55929, ALCB075866, 3 sheets]) .

Description.

Scandent shrub or liana, to 2 m. Stems cylindrical, hollow, 2-5 mm in diameter, frequently branching, glabrescent to sparsely pubescent; internodes 2.9-8.2 cm long; side shoots 3.0-4.5 cm long, sericeous. Leaves of main stem unknown. Side shoots with 3-4 leaves, these progressively larger along the shoot; blades 4.2-10.5 × 2.4-7.4 cm, ovate to broadly ovate, velutinous-pubescent, the venation pinnate, brochidodromous, with 4-6 secondary veins; the base rounded to truncate, the margins entire, ciliate, the apex obtuse; petioles 8-19 mm long, straight, velutinous-pubescent. Inflorescence corymbose, with 2-6 flowers; free portion of the peduncle 4-6 mm long, 1.8-2.1 cm long, the remainder adnate to the bracteole, sericeous-pubescent; bracteoles 5.0-5.7 × 2.7-3.1 cm, inserted ca. ¼ of the way along the pedicel or rarely lacking, ovate, velutinous-pubescent, the venation as the leaves, the base short-rounded, the margins entire, ciliate, the apex attenuate. Flowers incompletely known, 5-merous. Calyx with the tube campanulate, ca. 1.5 mm long, the lobes ca. 1.5 × 10-12 mm, ensiform, sericeous-pubescent. Corolla unknown; androecium and gynoecium unknown. Fruit inserted on the accrescent bracteole; calyx persistent, expanding to 12 mm long.

Distribution.

Endemic to the state of Bahia (Fig. 2 ).

Habitat.

Keraunea bullata is a species of forests in the transition from humid forests in the coastal Mata Atlântica phytogeographic domain and seasonally dry forests in the inland Caatinga domain. This forest is described on labels as "Caatinga arborea" (Guedes et al. 9176) and (Mori et al. 11534) as growing on rocky soils. This area has a metamorphic bedrock (often called crystalline in the literature, de Queiroz et al. 2017) and is quite edaphically distinct from the karstic outcrops that are home to K. brasiliensis and K. confusa .

Conservation status.

Keraunea bullata is known from only three localities with a combined EOO of ca. 6,300 km2. We know of no specific conservation threats to this species so provisionally assess it as Vulnerable (VU D2) under IUCN Red List criteria ( IUCN 2019).

Etymology.

Named for the bullate texture of the leaves and bracteoles.

Identification notes.

Keraunea bullata is highly distinct within its range. Despite also occurring in the same Mata Atlântica phytogeographic domain as K. capixaba , their habitat does not overlap. Keraunea bullata can be morphologically distinguished by its leaf venation (brochidodromous versus camptodromous) and texture (bullate and dull green versus smooth and glossy green).

Additional specimens examined.

Brazil. Bahia: Mun. Itambé, rod. BA-265, trecho Itapatinga / Caatiba, Faz. Serra Verde a 17 km da Rod. BR-415, [15°6'S, 40°22'W], 14 Mar. 1979, S.A. Mori et al. 11534 (CEPEC [CEPEC00016207], NY [03147645], RB [00725192]). Mun. Juraci, Vicinity of Machado Portela [13°10'S, 40°46'W], 19-23 Jun 1915, J.N. Rose & P.G. Russell 19979 (US [01341072, acc. # 762304) .

Figures

Figure 2. Distribution of species of the genus Keraunea. Shading denotes elevation; two letter codes represent the standardised two letter codes for the states of Brazil. Species are coloured as follows: blue, K. brasiliensis Cheek & Simao-Bianchini; black, K. bullata Moonlight & D. B. O. S. Cardoso; yellow, K. capixaba Lombardi; red, K. confusa Moonlight & D. B. O. S. Cardoso; green, K. velutina Moonlight & D. B. O. S. Cardoso.

Figure 4. Holotype of Keraunea bullata Moonlight & D. B. O. S. Cardoso, M. L. Guedes, D. M. Loureiro & D. L. Santana 9176 (ALCB [ALCB 075855, acc. # 55929, sheet 1]).