Jacaranda heterophylla M.M. Silva-Castro, 2017

Silva-Castro, Milene Maria Da, 2017, A new species of Jacaranda (Bignoniaceae) from the Chapada Diamantina (Bahia, Brazil), Phytotaxa 295 (3), pp. 287-291 : 288

Jacaranda heterophylla M.M. Silva-Castro , sp. nov. ( Fig. 1 )

Similar to J. grandifoliolata A.H. Gentry (1985: 246) with which it shares elliptic to obovate leaflets and similar to J. jasminoides ( Thunberg 1821: 36) Sandwith (1937: 232) with which it shares leaves pinnate at the base and bipinnate at the apex. However, it can be distinguished from J. grandifolialata by the number of leaflets (17–19 vs. 3–5 in J. grandifolialata ) and from J. jasminoides by the leaflet length (6–15 cm vs. 1–4 cm in J. jasminoides ).

Type:— BRAZIL: BAHIA, Palmeiras, 20 October 2002, (fl.), 12º34’ S, 41º23’ W, E. C. Smidt 260 (holotype HUEFS!).

Shrub to tree, ca. 2–6 m; branches cylindrical to subquadrangular, striated, glabrous, with lenticels. Leaves pinnate at the base, bipinnate at the apex, with 15–17 leaflets overall, (1–)3–5 leaflets per pinna; rachis subalate, pubescent; petiole 0.5–3 cm; leaflets 6–15 × 3.5–6 cm, elliptic to elliptic-obovate, coriaceous, apex acute and mucronate, margins entire, revolute, base acute to attenuate or asymmetrically cuneate, venation pinnate, green, shiny, rough, scabrous, with simple tector trichomes adaxially, greenish-yellow, pubescent to tomentose, with simple tector trichomes abaxially. Inflorescence thyrsoid. Calyx 8–8.5 × 5–6 mm, campanulate, chartaceous, 5-dentate, with conspicuous teeth, pubescent, with simple tector trichomes; corolla 4–4.5 × 1.8–2 cm, vinaceous, tubular-campanulate, membranaceous, lepidote; dorsal stamens 2–2.2 cm, ventral stamens 1.5–1.7 cm, anthers bi-thecate, thecae 1.5–2 mm; staminodes 2.3–2.5 cm, with glandular trichomes at the median apical region; nectary disc ca. 2 × 3 mm, annular; ovary ca. 3 × 2 mm, oval, glabrous, style 2.3–2.5 cm, stigma ca. 2 mm. Capsule (immature) 6.2–6.5 × 3.5–3.8 cm, obovate, apex cuspidate, margins plane, base cuneate; valves coriaceous, glabrous; seeds not seen.

Distribution: —Recorded only from Seasonally Dry Forests (known locally as Caatinga) from the Chapada Diamantina, Bahia, Brazil, where it occurs in the municipalities of Lençóis and Palmeiras (12º33’23”, 12º34’00”S and 41º23’00, 41º24’40”W) ( Fig. 2).

Phenology:—Found flowering in October and December, and fruiting in October.

Conservation Status: —Data Deficient (DD) ( IUCN 2012). Better assessment of its distribution in its natural environment is still required for a more complete assessment of its conservation status. The most recent herbarium material for this species was collected more than 20 years ago.

Etymology: —The epithet refers to the heterogeneious leaves, which are pinnate at the base and bipinnate at the apex.

Notes:— Jacaranda heterophylla resembles J. grandifoliolata by the elliptic to obovate leaflets and J. jasminoides by the leaves that are pinnate at the base and bipinnate at the apex. It differs from J. grandifoliolata by the higher leaflet number (15–17 vs. 3–5), shorter leaflet length (6–15 cm vs. 3–13 cm), rough and scabrous leaflet surface (vs. smooth and lepidote or glabrous), as well as by the pubescent calyx (vs. glabrous or with scattered minute trichomes), and oval ovary (vs. flattened-oblong) ( Table 1). However, these two species do not occur sympatrically, with J. grandifoliolata occurring exclusively in the restingas of the southern coast of Bahia, around the city of Ilhéus.

Jacaranda heterophylla differs vegetativelly from J. jasminoides by the quadrangular branchlets (vs. terete), the generally longer (6–15 cm vs. 1.8–4(–7) cm) and wider (3.5–6 cm vs. 2–(4) cm) leaflets, shiny and rough adaxial leaflet surface (vs. opaque and smooth, sometimes scabrous), and scabrous and non-bullate abaxial leaflet surface (vs. pilose to tomentose, sometimes scabrous, sub-bullate surface). Reproductively, J. heterophylla differs from J. jasminoides by the vinaceous corolla throughout (vs. lilac to purple or dark wine-colored externally, occasionally whitish internally), the lepidote corolla tube (vs. pubescent), and oval ovary (vs. flattened-ovate).

Candolle (1845) and Gentry & Morawetz (1992) recognized two sections in Jacaranda based on the number of anther thecae: Monolobos and Dilobos . Jacaranda heterophylla is bi-thecate and thus included in section Dilobos , the same section where J. grandifoliolata and J. jasminoides are placed.

Additional specimen examined (paratype):— BRASIL, Bahia: Lençóis, 05 Dez 1994, (fl., fr.), 12º33’23”S and 41º24’40”S, L.S. Funch 803 (HUEFS).

Figures

FIGURE 1. Jacaranda heterophylla. A. Leaf. B. Inflorescence detail. C. Calyx. D. Corolla showing androecium. E. Gynoecium. F. Transverse section of ovary. G. Capsule. Illustrated from E.C. Smidt 260 (leaf and capsule) and L.S.Funch 803 (inflorescence and flower).