Keraunea confusa 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

4. Keraunea confusa Moonlight & D.B.O.S.Cardoso sp. nov.

Fig. 6

Diagnosis.

Most similar to K. brasiliensis but differing in its larger leaves (to 18 × 12 cm versus to 7.5 × 4 cm) with brochidodromous (versus camptodromous) leaf venation and a rugose (versus flat) leaf texture and by its leaves and stems with a sericeous (versus hirtellous) indumentum.

Type.

Brazil. Bahia: Mun. Januária, distrito de Fabião, junto ao Abrigo do Malhador , 15°7.85'S, 44°15.17'W, 25 May 1997, J.A. Lombardi & A. Salino 1819 (holotype: BHCB [BHCB017209]; isotypes: HRCB [acc. #26438]; K [K001395055], UEC [UEC117783]) .

Description.

Scandent shrub or liana, to 4 m tall. Stems cylindrical, hollow, 2-5 mm in diameter, rarely branching, sericeous-pubescent with silky hairs; internodes 3.8-16.5 cm long; side shoots 2.6-3.5 cm long, sericeous-pubescent. Leaves of the main stem with the blades 9.5-17 × 5.6-13.5 cm, ovate, velutinous-pubescent, the venation pinnate, brochidodromous, with 5-7 secondary veins, the base truncate to subcordate, the margins entire, ciliate, the apex attenuate to acute; petioles of leaves on main stem 10-16 mm long, distinctly curved to 90° ¼ of the way along their length. Side shoots with 2-5 leaves, these progressively larger along the shoot; blades 2.1-18 × 3.0-12 cm, velutinous-pubescent, the venation as on leaves of the main stems, the base rounded to truncate, the margins entire, ciliate, the apex obtuse; petioles 3-25 mm long, sericeous-pubescent. Inflorescence corymbose, with 2-4 flowers; free portion of the peduncle 5-13 mm long, 2.2-2.8 cm long, the remainder adnate to the bracteole, sericeous-pubescent; bracteole 4.9-5.6 × 2.7-5.1 cm, inserted ca. ⅓ of the way along the pedicel or rarely lacking, ovate, sericeous-pubescent, the venation as the leaves, the base short cuneate, 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. 7-9 × 1.5 mm, ensiform, sericeous-pubescent. Corolla unknown; androecium and gynoecium unknown. Fruit inserted on the accrescent bracteole; calyx persistent, expanding to 9 mm long.

Distribution.

Keraunea confusa is endemic to Brazil and to the state of Minas Gerais (Fig. 2 ).

Habitat.

All collections of K. confusa are from karstic (limestone) areas, where plants have been collected growing over rocks and vegetation in the understory of Caatinga seasonally dry tropical forest vegetation.

Conservation status.

Keraunea confusa is known from two localities and has an AOO of ca. 12 km2. Two of the known collections (Lombardi & Salino 1819, Lombardi 2107) were made within Parque Nacional Cavernas do Peruaçu, which includes extensive karst limestone habitat suitable for the species. We know of no specific threats to this species but provide a preliminary assessment as Vulnerable (VU D2) because of the species’ few known localities ( IUCN 2019).

Etymology.

The epithet refers to the confusion that has surrounded the taxonomic history of this species, which was both included within the original circumscription of the type species and the placement of the genus in the wrong family by Cheek and Simão-Bianchini (2013).

Identification notes.

Keraunea confusa is one of two species of the genus with brochidodromous venation, the other of which is K. bullata . It is distinguished from K. bullata by its generally bigger leaves measuring 9.5-17 cm long (versus 4.2-10.5 cm long), rugose (versus bullate) leaf texture and by the tertiary veins, which are plane to the lower leaf surface (versus raised).

Additional specimens examined

(paratypes). Brazil. Minas Gerais: Mun. Manga, BR-135, entre Montalvânia e Manga, afloramento de calcário do lado esquerdo a ca. 400 m da rodovia sentido Manga-Januária, 14°30'44.8"S, 44°10'31.8"W, 5 Dec. 2022, D. Cardoso et al. 4916 (ALCB, HUEFS, TCD, RB), D. Cardoso et al. 4918 (ALCB, HUEFS, TCD, RB); Mun. Januária, distrito de Fabião, junto ao Abrigo do Malhador , 15°7'16"- 15°8'57"S, 44°15'20"- 44°14'13"W, 26 Oct. 1997, J.A. Lombardi 2107 (BHCB [BHCB017210], K [K000593363]) .

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 6. Habitat and morphology of Keraunea confusa Moonlight & D. B. O. S. Cardoso A-C karstic Caatinga seasonally dry tropical forest in northern Minas Gerais D-G habit H-I branching pattern J close up of side shoot. All photographs by Domingos Cardoso.