Astraea paulina Didrichsen (1857: 138)

Silva, Otávio Luis Marques Da, Banzato, Ticyana Carone, Bedendo, Ivan Paulo & Cordeiro, Inês, 2017, A report of infestation by phytoplasmas in Astraea (Euphorbiaceae) and its taxonomic implications in Astraea douradensis, Phytotaxa 332 (2), pp. 195-198 : 197

Astraea paulina Didrichsen (1857: 138)

Type:— BRAZIL. São Paulo: Itú, February 1834, N. T. Lund s.n. (holotype C, isotype G00312455!).

= Astraea douradensis (Steyerm.) Caruzo in Caruzo et al. (2014: 127). Croton douradensis Steyermark (1958: 4) .

Type:— BRAZIL. Goiás: in gallery forest along stream 17 km east of Formoso, region of the southern Serra Dourada at 48 o 40’ W, 13 o 40’ S, 19 May 1956, E.Y. Dawson 14973 (holotype R!, isotypes F!, RSA!).

It is important to notice that another species of Astraea may show the same morphological traits as result of infestation by phytoplasmas. During our fieldwork, we found individuals of Astraea manihot in São Paulo (southeastern Brazil, O.L.M. Silva 235, SP 475344!) possessing all the malformations reported above (Fig. 1F–G).

Leaf samples from individuals of Astraea manihot from São Paulo were submitted to DNA extraction with the DNeasy Plant Mini Kit and we could trace phytoplasmas in these samples through polymerase chain reaction (PCR). In PCR we amplified genomic fragments of 1.2 kb with the primers 16F2n/16 R 2 (Lee & Gundersern 1996) in reactions with 20 ng of total DNA, 200 μM of each dNTP and 0.4 to 1.0 μM pf each primer. PCR program consisted of an initial denaturation at 94 °C for 2 min, followed by 35 cycles of denaturation at 94 °C for 1 min, annealing at 55 °C for 2 min and extension at 72 °C for 3 min, and final extension at 72 °C for 3 min. PCR products were analyzed through electrophoresis in 1 % agarose gel colored with Sybr Safe (Invitrogen) and visualized in UV light transilluminator.

Although morphologically similar, Astraea manihot may be distinguished from A. paulina , in their healthy form, by having pedicels of pistillate flowers with up to 1 cm long (vs. subsessile pistillate flowers, with pedicels up to 0.3 cm long in Astraea paulina , while in infested plants we observe pedicels with 1.5–3 cm long) and leaves (3–)5(–7)- partite (vs. entire or 2–3-partite leaves in Astraea paulina ). Therefore, special attention is required when identifying individuals of Astraea presenting the suite characteristics linked to A. douradensis . Nonetheless, as far as we know, within Astraea , only A. manihot and A. paulina are susceptible to infestation by phytoplasmas.