Parasenegalia Seigler & Ebinger, 2017

Seigler, David S., Ebinger, John E., Riggins, Chance W., Terra, Vanessa & Miller, Joseph T., 2017, Parasenegalia and Pseudosenegalia (Fabaceae): New Genera of the Mimosoideae, Novon 25, pp. 180-205 : 181-183

I. Parasenegalia Seigler & Ebinger , gen. nov.

TYPE: Acacia skleroxyla Tussac, Fl. Antill. 1: 146– 14 8, pl. 2 1. 18 0 8 [1 80 8–1 81 3]

[≡ Parasenegalia skleroxyla (Tussac) Seigler & Ebinger ].

Trees, shrubs, or lianas, some to 25 m; twigs not flexuous, terete or nearly so; short shoots absent; prickles and stipular spines absent. Leaves alternate, bipinnate; stipules small, linear, symmetrical, herbaceous, tardily deciduous to persistent, rarely absent; petioles adaxially grooved, 10–50 mm long; petiolar glands present, sessile, solitary; rachis adaxially grooved, usually with a gland between some pairs of pinnae; pinnae 3 to 20 pairs/leaf, opposite; paraphyllidia present or absent; leaflets 7 to 65 pairs/ pinna, linear to oblong, 1 to 5 veins from the base, glabrous to puberulent, midvein subcentral to submarginal. Inflorescence a globose head or cylindrical spike, solitary to small clusters in leaf axis or in large pseudoracemes or pseudopanicles of globose heads. Flowers bracteate, sessile, actinomorphic, sympetalous, 5-merous, with a basal copular nectariferous disk; stamens 40 to 140, distinct, attached along the side of the nectariferous disk, exserted; anthers small, dorsifixed, dehiscing vertically, with a small stalked gland usually present; ovary mostly sessile to subsessile (rarely with a stipe to 1.6 mm long); style filiform; stigma filiform. Legumes straight to slightly curved, flattened, oblong, eglandular, dehiscing along both sutures (sometimes tardily so). Seeds uniseriate, not surrounded by pulp, ovoid to ellipsoid, flattened, sometimes with a marginal wing; pleurogram sometimes present, sometimes covering most of the seed.

Habitat and distribution. Occurring in tropical areas of the New World, Parasenegalia is comprised of three species restricted to the Caribbean, one in Belize and Guatemala, and three scattered in South America.

TAXONOMIC KEY TO SPECIES OF PARASENEGALIA

1. Inflorescence a cylindrical spike.

2. Leaflets 30 to 65 pairs/pinna; distance between leaflet pairs 0.7–1.6 mm (Dominican Republic & Haiti).................................................................. P. skleroxyla (Tussac) Seigler & Ebinger

2 '. Leaflets 7 to 31 pairs/pinna; distance between leaflet pairs 1.4–9.5 mm.

3. Leaflets 1.8–3.2 mm wide; distance between leaflet pairs 1.4–4 mm; leaflet margins not revolute

(Central America)...................................................... P. lundellii Seigler & Ebinger

3 '. Leaflets 4–11.3 mm wide; distance between leaflets pairs 3.8–9.5 mm; leaflet margins slightly revolute

(Caribbean)...................................................... P. muricata (L.) Seigler & Ebinger

1 '. Inflorescence a globose to subglobose head.

4. Petiolar gland columnar, the apex 0.3–0.5 mm across; inflorescence receptacle elongated (Brazil)..................................................................... P. santosii (G. P. Lewis) Seigler & Ebinger

4 '. Petiolar gland sessile, not columnar, the apex mostly more than 0.6 mm across; inflorescence receptacle not elongated, usually subglobose to globose.

5. Leaflets 3–7 X 0.8–2.1 mm; distance between leaflet pairs 0.8–2.1 mm; leaflet midveins bluish purple beneath (South America)............................... P. visco (Lorentz ex Griseb.) Seigler & Ebinger

5 '. Leaflets 7–20 X 2.2–8.5 mm; distance between leaflet pairs 2.5–7 mm; leaflet midveins not bluish purple.

6. Inflorescence 6.5–10 mm across; 6 to 9 pinna pairs/leaf (Bolivia, Peru).....................

................................................. P. rurrenabaqueana (Rusby) Seigler & Ebinger.

6 '. Inflorescence 9–14 mm across; 3 to 6 (7) pinna pairs/leaf (Caribbean).............................................................................. P. vogeliana (Steud.) Seigler & Ebinger