Croton longicarpus Pereira, Caruzo & Riina (2017: 830)

Pereira, Amanda Da Paixão Noronha, Riina, Ricarda & Caruzo, Maria Beatriz Rossi, 2022, Croton (Euphorbiaceae) of the Brazilian state of Paraná: an annotated checklist, species distribution, and identification key, Phytotaxa 570 (3), pp. 231-274 : 251-252

21. Croton longicarpus Pereira, Caruzo & Riina (2017: 830) .

Type: — BRAZIL. Paraná: Rio Branco do Sul , rodovia PR-092, sentido Cerro Azul , próximo ao km 40, orla de Floresta Ombrófila Mista, 25°08’00.7”S, 49°20’54.8”W, 940 m, 22 November 2016, A.P N. Pereira, M.B R. Caruzo & R. Riina 46 (holotype SP 489505 !; isotypes MBM!, NY!, RB!) ( Fig. 13 , A–E) .

This shrub can be easily recognized because of the indument and shape of the pistillate sepals (lepidote, narrowly spatulate) and its narrowly ellipsoid ovaries/capsules. In herbaria, part of the Croton longicarpus collections have been previously misidentified as C. splendidus . These two species can be distinguished by leaf shape (narrowly to broadly elliptic in C. splendidus vs. narrowly lanceolate to lanceolate in C. longicarpus ), and lepidote trichomes in styles (absent in C. splendidus vs. present in C. longicarpus ) ( Pereira et al. 2017b). Croton longicarpus also resembles C. uruguayensis due to their long and lax inflorescences, and narrow leaves. Despite this, C. longicarpus differs by its adaxial leaf surface covered by stellate trichomes, bisexual inflorescences, narrowly spatulate pistillate sepals, narrowly ellipsoid capsules, and styles covered by lepidote trichomes, whereas in C. uruguayensis the adaxial leaf surface is glabrous, the inflorescences are unisexual, the pistillate sepals are oblong, the capsules are globose, and the styles are glabrous. Croton longicarpus belongs to section Lamprocroton subsect. Lamprocroton ( van Ee & Berry 2011) .

Distribution and habitat: —It is restricted to southern Brazil (PR, RS), growing in open vegetation and edges of Araucaria forest , between 860 and 1000 m elevation ( Pereira et al. 2017b) ( Fig. 12 ).

Phenology: —Flowering from February to March and September to December, and fruiting November to March.

Representative specimens:— PARANÁ: Coronel Domingos Soares, São João, 26°11’39”S, 52°02’24”W, 1045, 22 September 2014, J. T. Motta & J. M. Silva 4435 ( MBM). Mallet, Rio Bonito, 20 April 2005, O. S. Ribas, R. Wasum & L.Seur 6844 B ( MBM). Rio Branco do Sul, Caverna de Caximba, 14 December 1996, G. Tiepolo & A. C. Svolenski 643 ( EFC, MBM); Rodovia PR-092, sentido Cerro Azul, próximo ao km 40, 25°08’00.7’’S, 49°20’54.8’’W, 940 m, 22 November 2016, A. P. N. Pereira, M. B. R. Caruzo & R. Riina 46 ( SP).

Figures

FIGURE 12. Map showing the known geographic distributions of Croton longicarpus, C. lundianus, C.macrobothrys, and C. muellerianus in Paraná state.

FIGURE 13. Croton longicarpus. A. Habit. B. Inflorescence. C. Staminate flower. D. Pistillate flower. E. Capsule. C. lundianus. F. Inflorescence with a noticeable sterile region between the pistillate and staminate flowers. G. Staminate flowers. H. Pistillate flowers; note the characteristic white sepals with serrate margins. I. Capsules. C. macrobothrys. J. Trunk, showing red latex where scored with a knife. K. Stipitate acropetiolar nectary glands. L. Young capsule with persistent, bifid stigmas. Photos: A–E: A.P.N. Pereira, F–I: O.L.M. Silva, J–L: R.F. Santos.