Augustea Iamonico, 2015

Iamonico, Duilio, 2015, Augustea (Polycarpaeae, Caryophyllaceae), a new genus from South America, Phytotaxa 236 (1), pp. 71-78 : 72

Augustea Iamonico , gen. nov.

Type: Augustea suffruticosa (Griseb.) Iamonico

Basionym: Polycarpon suffruticosum Grisebach (1874: 77 − 78) .

= Polycarpon sect. monostigma Hassler (1907: 12)

Type: Polycarpon anomalum Hassler (1907: 12 − 13) .

Description: ―Shrubs (chamaephytes/nanophanerophytes) up to 50 cm tall. Stem woody at the base, branched, branches glabrous or minutely pulverulent, ridged. Leaves often in whorls of 4 or in whorls of 4 (rarely 6) shortly petiolate or sessile, blade lanceolate (apex acute, base cuneate) or obovate to orbicular (apex rounded to obtuse, base obtuse), usually glabrous (pulverulent when young). Inflorescence terminal and dichotomous cymes, 2 − 6-branched. Flowers subsessile; sepals 5, ovate-orbicular, obtuse or acute, 1 − 3-nerved, keeled, hyaline on margins; petals 5, oblong to obovate, obtuse, shorter than the sepals, white; stamens 3 − 5, perigynous; style 1, stigmas 1 − 3. Fruits (capsule) ovoid, longer than the calyx, opening by non-involute valves; seeds 3 − 35, lunate-fusiform, surface nearly smooth, brown.

Etymology: ―Dedicated to August Grisebach, the German botanist who first described one of the three members of the new genus ( A. suffruticosa ).

Proposal vernacular name: ―Grisebach’s fourleaf allseed.

Distribution: ―South America ( Argentina, Bolivia, Chile, Paraguay).

Notes: ― Hassler (1907: 12 − 13) described the new section Monostigma providing a short diagnosis (“ Petalis 5 obovatis, breviter unguiculatis, antheris 3, stylo elongato, stigmate subcapitato… ”) also stating “ species unica adhuc nota: Polycarpon anomalum Hassler spec. nov. ”. The author also pointed out that “ Notre nouvelle espéce est…l’unique Polycarpée à un seul stigmate ” (“Our new species is…the only Polycarpon taxon with a single stigma”). On the basis of this character, Hassler (l.c.) separated his new taxon at sectional level. We here propose to synonymize the Hassler’s sectional name with the new genus Augustea (new synonymy).

The genus Augustea as recognized here includes three South American species: A. suffruticosa , A. coquimbense and A. anomala . They differ from each other in both vegetative and sexual characters:

1. Style with a one stigma..................................................................................................................................................... A. anomala

- Style with three stigmas......................................................................................................................................................................2

2. Leaves usually in whorls of 4, blade usually lanceolate (10 − 40 mm long), apex usually acute, base cuneate; sepals usually acute, 3-nerved; capsule 4.5–5.5 mm long; seeds 25 − 35 per capsule .................................................................................... A. suffruticosa

- Leaves opposite, blade obovate to orbicular (5 − 9 mm long), apex rounded, base obtuse; sepals obtuse, 1-nerved; capsule less than 2 mm long; seeds 3 − 7 per capsule.............................................................................................................................. A. coquimbense