Croton sacaquinha Croizat (1944: 456)

Rossine, Yuri, Melo, André Laurênio De, Athiê-Souza, Sarah Maria & Sales, Margareth Ferreira De, 2023, Understanding the “ Marmeleiros ”: a taxonomic treatment of Croton sect. Lasiogyne (Euphorbiaceae) in Brazil, Phytotaxa 584 (4), pp. 219-250 : 238-241

9. Croton sacaquinha Croizat (1944: 456) .

Holotype: BRAZIL. Amazonas : Manaus, 1935, circa urbem culta et subspon tanea, without date, W.A. Ducke 384 ( A [ A00047409 !]; isotypes: K [ K000254427 !], NY [ NY00262948 !], R [ R000055704 !]) . Fig. 8 (l–p), 9 (a)

Description: —Monoecious shrub to tree, 0.3–10 m tall; latex not seen; branching sympodial, branches cylindrical, slightly striated, brown to reddish; trichomes stellate-lepidote to dentate-lepidote. Leaves alternate; stipules linear, ca. 0.4 cm long, usually deciduous, with stellate-lepidote trichomes; petiole cylindrical, 0.4–1 cm long, with dentatelepidote trichomes; leaf blade chartaceous, lanceolate, 2.5–6 × 1–1.8 cm, strongly bifacial, adaxial face green to dark green with stellate-lepidote trichomes to glabrescent, abaxial face shiny, silver to ferruginous with stellate-lepidote to lepidote trichomes, base rounded to obtuse, margins entire, apex acute to narrowly acute, venation eucamptodromous, with 8–14 secondary veins. Thyrses 3–10 cm long, axillary, with stellate-lepidote to dentate-lepidote trichomes, peduncle 0.4–0.7 cm long; cymules unisexual, lax, up to 2 staminate flowers, with solitary pistillate flowers; bracts linear, deciduous, ca. 2 mm long, margins entire, apex acute, with stellate-lepidote trichomes. Staminate flower with pedicels ca. 2 mm long; sepals silver to yellowish, united for ⅓ of their length, lobes ovate, 1–2 × 0.6–1.4 mm, margins entire, apex acute, with stellate-lepidote trichomes externally, stellate internally; petals yellowish, oblong, 2–2.5 × 1 mm, margins entire, apex rounded, with simple trichomes; stamens 13–15 (17), filament 1.5–2.8 mm long, anther rounded, ca. 0.7–0.8 mm diam.; nectary disk 5-lobed, apex of lobes rounded, with simple trichomes. Sessile to subsessile pistillate flower, pedicel up to 1 mm long; sepals silver to ferruginous, free, ovate, equal in size, rarely slightly unequal, 4–6 × 2.5–4 mm, slightly reduplicated vertically, margins entire, apex acute, with stellate-lepidote trichomes externally, simple to stellate internally; petals yellow, oblong, 3–5 × 1–2 mm, margins entire, apex rounded, with dentate-lepidote trichomes; ovary spheroid, 3–3.7 mm diam., with stellate-lepidote trichomes; styles ascending, free, multipartite, up to 28 stigmatic tips, with stellate-lepidote trichomes; nectary disk 5-lobed, apex of lobes rounded, glabrous. Capsule ferruginous, ovoid, 4–4.5 × 2–2.8 mm, 3-lobed, surface non-muricate, with dentate-lepidote trichomes; columella ca. 2 mm, striated, apex flattened. Seed brown, ellipsoid, 3–3.5 × 2.5 mm, surface rugose, caruncle elliptic.

Vernacular names: — Assacaca, cheira, macacaparonga, macapuanga piaçoca, piaçoquinha, piassaca sacaca, sacaquinha, and sacaca-fêmea.

Distribution and habitat, conservation status, and phenology: — Croton sacaquinha has been recorded for Guyana and Brazil ( Gomes 2006). In the latter country, it occurs in the Amazon domain, being found on riverbanks in Amazonas, Mato Grosso, Rondônia, and Pará (Caruzo et al. 2022) ( Fig. 9 , a). Croton sacaquinha has a small AOO (88 km 2), but has a wide EOO 1,946,556.747 km 2), occurs in areas of difficult access and is cultivated in some locations in the north of the country, in addition to have populations occurring in protected areas, such as the Jaú National Park (AM), the Amazon National Park (AM), the Verde Para Sempre Extractive Reserve (PA), and the Trombetas River (AM) and Lake Cuni„ Extractive Reserves (RR). For such reasons, we classify this species as of Least Concern (LC). Flowering and fruiting throughout the year.

Notes: — Croton sacaquinha can be easily distinguished by its sympodial branching, ferruginous to reddish indumentum (mainly on the petioles and younger branches), densely velutine petioles, lanceolate leaf blade, and as the only species with pistillate flowers with developed petals in the section Lasiogyne in Brazil.

Representative specimens: — BRAZIL. Amazonas: Novo Air „o, Parque Nacional do Jaú, Rio Jaú, 22º8’33” S, 62º45’00” W, 2 June 1995, E. Rodrigues 37 ( INPA). Pará: Oriximin„, Cachoeira Porteira, 1º09’19” S, 57º03’59” W, 2 July 1980, C . Davidson 10696 ( INPA). Rondônia: Porto Velho , mata do km 14 da estrada de rodagem, 3 December 1949, N. T . Silva 395 ( IAN) .

Figures

FIGURE 8. a–f Croton suassunae: a flowering branch (staminate), b flowering branch (pistillate), both a and b showing sympodial ramification, c lanceolate stipules, d staminate flower of ca. 15 stamens, e pistillate flower with sepals slightly reduplicated vertically, spheroid ovary, and ascendant and 2-fid styles, f spheroid fruit, showing sepals internally glabrous.g–k C. tricolor: g flowering branch with monopodial ramification h lanceolate stipules, i staminate flower of ca. 12 stamens, j pistillate flower with sepals strongly reduplicated vertically, glabrous internally, ovoid ovary and, patent and multipartite styles k long ellipsoid to ovoid fruit.

FIGURE 9. Distribution of some species of section Lasiogyne. a Croton limae, C. micans and C. sacaquinha; b C. suassunae and C. tricolor.