Tetrameranthus trichocarpus Maas & Westra, 2019

Maas, Paul J. M., Westra, Lubbert Y. Th., Chatrou, Lars W., Verspagen, Nadja, Rainer, Heimo, Zamora, Nelson A. & Erkens, Roy H. J., 2019, Twelve new and exciting Annonaceae from the Neotropics, PhytoKeys 126, pp. 25-69 : 47-49

Tetrameranthus trichocarpus Maas & Westra sp. nov. Figs 21 , 22

Diagnosis.

Tetrameranthus trichocarpus resembles T. globuliferus Westra from Ecuador in leaf shape and in the young twigs covered with brown, stellate hairs, but differs by 5-merous (vs. 6-merous) flowers and hairy (vs. glabrous) monocarps, and also by smaller leaves (16-28 vs. 27-37 cm long).

Type.

PERU, Loreto: Prov. Maynas, Distr. Medio Putumayo, Inventario Rápido #25, Campamento Bajo Ere , 2°01'07.4"S, 73°15'13.4"W, 125-175 m, 22 Oct 2012, Ríos et al. 2608 (holotype: F! [F2321026]; isotypes: F!, L!) .

Description.

Tree ca. 10 m tall. Young twigs and petioles densely covered with stiff, brown, mostly stellate hairs to 1-2 mm long. Leaves: petioles 8-10 by 3-4 mm; lamina narrowly obovate, 16-28 by 5-8 mm (leaf index 2.5-4), bright shiny green above and pale green below in vivo, dark greenish grey above and greenish brown below in in sicco, densely covered with brown hairs ≥1 mm long on primary vein and less densely so on secondary veins above, elsewhere rather densely to sparsely covered with stellate and simple hairs, to at last glabrous above, densely to rather densely covered on primary vein and secondary veins below, elsewhere sparsely covered with stellate and simple hairs mainly on lesser veins below, base narrowly acute, apex acuminate (acumen ca. 5 mm long), primary vein slightly prominent to almost flat above, becoming canaliculate in sicco, secondary veins 12-20 on either side of primary vein, mostly loop-forming, shortest distance between loops and margin 1-2 mm, tertiary veins percurrent. Flowers solitary in axils of leaves; peduncles 7-10 by 2 mm; pedicels 30-35 by 2{-3} mm, to 4 mm diam. in fruit, peduncles and pedicels densely covered with hairs as on twigs; bracts not seen; perianth in 5-merous whorls, petals pale greenish creamy suffused with purple, inner base of inner petals yellowish white, sepals ( ±) free, narrowly trangular, 4-5 by 10-12 mm, outer side densely covered with hairs as on pedicels to 1 mm long, the inner side same but less densely; outer petals narrowly elliptic-ovate or elliptic-oblong, 30-37 by 10-12 mm, inner side with basal callus to ca. 2/5 of the length and triangular in shape, inner petals narrowly obtriangular-elliptic, about as long as outer petals, slightly narrower than outer petals, markedly recurved about the middle, basal callus on inner side ca. 2/3 of the length and almost touching the side, all petals densely covered with similar though somewhat smaller hairs as on sepals, except for callose parts sparsely so; stamens ∞, apical prolongation of connective shield-like, ca. 1 mm in diam., glabrous; carpels ca. 8, ca. 4 mm long, densely covered with erect hairs to 0.5 mm long on the abaxial side. Monocarps 4-6, pinkish green and somewhat shiny in vivo, brown and with shriveled wall in sicco, ovoid to globose, 4-4.5{-5} by 3-3.5{-4.5} cm, with a conical, obtuse apicule ca. 3-4 mm long, with an oblique constriction (2-seeded forms, only visible in sicco), densely to rather densely covered with stiffly, erect, whitish, stellate and simple hairs. Seeds (1-)2 per monocarp.

Distribution.

Peru (Loreto) (Fig. 3 ).

Habitat and ecology.

In moist forest on sandy soil. At an elevation of 125-175 m. Flowering and fruiting: October.

Notes.

Tetrameranthus trichocarpus is very similar to T. globuliferus Westra, from Ecuador ( Maas et al. 1988), and also a narrow endemic. Apart from being 5-merous in T. trichocarpus vs. 6-merous in T. globuliferus , the flowers of the two species resemble each other very much. Both these species share two features with the far-remote T. guianensis Westra & Maas, namely a thick fruit wall that shrivels with drying, and an indument of coarse, stellate and simple hairs on vegetative parts. To our knowledge, this is the only species of Tetrameranthus with permanently hairy fruits.

Preliminary IUCN conservation status.

DD. This species is only known from one collection and therefore no AOO and EOO could be calculated. Also, no other assessment criterium could be used for this species since no information is available on the current population size and population trend of this species. The species seems to occur in a large, pristine forest area and habitat loss does not seem to be an immediate threat to Tetrameranthus trichocarpus . However, given the overall lack of data, it was assessed as Data Deficient.

Figures

Figure 3. Distribution map of Annona caput-medusae, A. oleifolia, Guatteria attenuata, G. kamakusensis, G. pseudoferruginea, Klarobelia rocioae, and Xylopia longicaudata.

Figure 21. Tetrameranthus trichocarpus Maas & Westra. A Flowering and fruiting branch B detail of same C top of branchlet with 2 (young) flowers D flower E fruit F Isau Huamantupa holding collected material. Photographs by I. Huamantupa C.

Figure 22. Tetrameranthus trichocarpus Maas & Westra. Fruiting branch (M. Rios et al. 2608, holotype F).