Euphorbia hyssopifolia Linnaeus (1759: 1048)

Silva, Otávio Luis Marques Da, Cordeiro, Inês & Caruzo, Maria Beatriz Rossi, 2014, Synopsis of Euphorbia (Euphorbiaceae) in the state of São Paulo, Brazil, Phytotaxa 181 (4), pp. 193-215 : 200

10. Euphorbia hyssopifolia Linnaeus (1759: 1048) ( Fig. 3F–H ). Lectotype (designated by Fawcett & Rendle 1920: 339):— JAMAICA. Locality unknown, Anonymous s.n. (LINN 630.9!).

Distribution and habitat:— Euphorbia hyssopifolia is a worldwide tropical and subtropical weed. In the State of São Paulo the species is very common in cerrado vegetation and disturbed areas.

Representative Specimen:— BRAZIL. São Paulo: Angatuba , 17 December 2013, O.L.M. Silva et al. 40 (SP) .

Taxonomic notes:— Euphorbia hyssopifolia is similar to E. foliolosa and E. bahiensis . The species can be distinguished from E. foliolosa by leaf venation and styles (see notes on Euphorbia foliolosa ). The distinction between E. hyssopifolia and E. bahiensis lies on their dichasia and their habitat (see notes on Euphorbia bahiensis ).

Euphorbia hyssopifolia is also similar to another common weedy species, E. hypericifolia Linnaeus (1753: 454) which was however not observed among the herbarium collections examined or during the fieldwork for this treatment. Euphorbia hypericifolia may be distinguished from E. hyssopifolia by the synflorescences with aphyllous distal nodes (vs. distal nodes with narrow and smaller leaves in E. hyssopifolia ) and fruits 1.3–1.4 × 1.1–1.5 mm (vs. 1.5–1.6 × 1.7–1.8 mm in E. hyssopifolia ).

Figures

FIGURE 3. A–B: Euphorbia heterophylla. A. habit, B. branch with cyathia. C–E: Euphorbia hirta. C. habit, D. branch with cyathia, E. cyathium. F–H: Euphorbia hyssopifolia. F. habit, G. synflorescence, H. branch with cyathia. Photos: O.L.M. Silva.