Hornschuchia (Annonaceae), an endemic and threatened genus from the Brazilian Atlantic Forest
Author
Vilela, Lucas
Universidade de São Paulo, Instituto de Biociências, Departamento de Botânica, Rua do Matão, 277, ed. Sobre-as-Ondas, 05508 - 090 São Paulo, SP, Brazil. & Universidade Anhembi-Morumbi, Escola de Ciências da Saúde, Rua Dr. Almeida Lima, 1134, 03101 - 001, Mooca, São Paulo, SP, Brazil.
vilela.lucas@hotmail.com
Author
Lopes, Jenifer De Carvalho
Universidade de São Paulo, Instituto de Biociências, Departamento de Botânica, Rua do Matão, 277, ed. Sobre-as-Ondas, 05508 - 090 São Paulo, SP, Brazil.
jenifer.clopes@gmail.com
text
European Journal of Taxonomy
2022
2022-07-11
828
75
108
http://dx.doi.org/10.5852/ejt.2022.828.1859
journal article
10.5852/ejt.2022.828.1859
c5427427-07fc-4449-ba86-25f19cd47482
2118-9773
6823766
Genus
Hornschuchia
Nees
Flora
4 (1): 302 (
Nees 1821
)
. −
Type
species:
Hornschuchia bryotrophe
Nees.
Mosenodendron
R.E.Fr.,
Kongliga Svenska Vetenskaps Akademiens Handlingar
, ser. 3
34 (5): 8 (
Fries 1900
)
.
–
Type
species:
Mosenodendron insigne
R.E.Fr.
Description
Trees to shrubs. Leaves chartaceous to coriaceous with primary vein impressed adaxially. Inflorescence 1-flowered or 2–22-flowered; axillary, supra-axillary, terminal or cauliflorous, i.e., ramiflory, trunciflory, flagelliflory. Flowers white, rarely pinkish, trimerous; three sepals and six petals in two whorls; calyx with sepals completely connate, rarely connate at the base; corolla with linear petals; stamens 3–18; carpels 2–9. Fruit with 1–5 monocarps, monocarps obovate, globose, ellipsoid, obloid, fusiform; stipe
1.5–9 mm
long, subsessile to sessile. Seed 1–8, globose, obovoid, obloid-ellipsoid, ellipsoid, flattened-ellipsoid, with aril, rarely without aril.
Hornschuchia
is recognized by its small and white flowers, with linear petals and cupuliform calyx. It is similar to
Trigynaea
and
Bocagea
; however, the petals in these two genera are ovate, elliptic or lanceolate (
Johnson & Murray 1995
).
Key to the species of
Hornschuchia
Nees
1. Leaves with commissural veins evident .............................................................
H. bryotrophe
Nees
− Leaves without commissural veins ................................................................................................... 2
2. Inflorescence axillary, supra-axillary to terminal or ramiflorous ...................................................... 3
− Cauliflorous, except ramiflorous ......................................................................................................11
3. Inflorescence 1-flowered ................................................................................................................... 4
− Inflorescence 2–22-flowered ........................................................................................................... 10
4. Calyx connate at the base with triangular apex .......................................
H. citriodora
D.M.Johnson
− Calyx completely connate (cupuliform) with truncate apex ............................................................. 5
5. Calyx
3–8 mm
long .......................................................................................................................... 6
− Calyx 1–2(–3) mm long .................................................................................................................... 8
6. Stamens 10,
4 mm
long, carpels
5.5 mm
long. Monocarp obloid with acute apex, 20–24 ×
9–12 mm
, stipe
1–2 mm
long ....................................................................
H. mellosilvae
L.Vilela & J.C.Lopes
− Stamens 3–6,
2–3 mm
long, carpels
2–3 mm
long. Monocarp globose to ellipsoid with rounded apex, 8–13 ×
5–9 mm
, sessile .................................................................................................................... 7
7. Floral bud cylindrical with obtuse apex. Fruit 1 monocarp with persistent calyx .............................. ..................................................................................................................
H. lianarum
D.M.Johnson
− Floral bud globose to ovoid to conical with acute apex. Fruit 2–5 monocarps with caducous calyx ... ....................................................................................
H. mediterranea
Mello-Silva & D.M.Johnson
8. Calyx glabrescent. Monocarp sessile ...................................................................
H. polyantha
Maas
− Calyx densely covered in trichomes. Monocarp stipe
1.5–3 mm
long ............................................. 9
9. Leaves narrowly elliptic to elliptic, oblanceolate to narrowly oblong, obovate or rarely lanceolate. Pedicel
7–37 mm
long ............................................................................................
H. myrtillus
Nees
− Leaves narrowly ovate to ovate or lanceolate. Pedicel
1–7 mm
long .....
H. alba
(A.St.-Hil.) R.E.Fr.
10. Floral bud cylindrical. Monocarp fusiform,
5–8 mm
wide, densely covered in trichomes, whitish in vivo
...........................................................................................................
H. obliqua
Maas & Setten
− Floral bud conical. Monocarp globose,
16–19 mm
wide, glabrous, green in vivo ............................ .....................................................................................................................
H. santosii
D.M.Johnson
11. Trunciflory ...................................................................................................................................... 12
− Flagelliflory, i.e., inflorescence branches
4.5–100 cm
long, emerging from the basal part of the trunk and running near the soil ................................................................................................................. 13
12. Inflorescence branches
6–19 cm
long ......................................................
H. leptandra
D.M.Johnson
− Inflorescence emerging close to the trunk .............................................
H. cauliflora
Maas & Setten
13. Calyx glabrescent. Bracts caducous ....................................................................
H. polyantha
Maas
− Calyx densely covered in trichomes. Bracts persistent ..........................................
H. myrtillus
Nees