A new Uvaria L. species (Annonaceae)
from northern Mozambique
Thierry DEROIN
Muséum national d’Histoire naturelle,
Département Systématique et Évolution (UMR 7205)
case postale 39, 57 rue Cuvier, F-75231 Paris cedex 05 (France)
deroin@mnhn.fr
Mervyn LÖTTER
Restoration and Conservation Biology Research Group, School of Animal,
Plant and Environmental Sciences, University of the Witwatersrand,
Johannesburg, PO WITS 2050 (South Africa)
mervyn.lotter@gmail.com
Deroin T. & Lötter M. 2013. — A new Uvaria L. species (Annonaceae) from northern Mozambique. Adansonia, sér. 3, 35 (2): 227-234. http://dx.doi.org/10.5252/a2013n2a4
KEY WORDS
Cabo Delgado,
new species,
systematics,
Rovuma River,
Critically Endangered.
ABSTRACT
A new species Uvaria rovumae Deroin & Lötter, sp. nov. is described, illustrated and mapped from Cabo Delgado Province in northern Mozambique.
Its morphology, as well as systematic affinities, habitat and conservation status
are briefly discussed. Very similar to U. tanzaniae Verdc. by its habit, it differs
mainly by its free sepals, inner petals slightly unguiculate and a high carpel
number (>35). Uvaria rovumae Deroin & Lötter, sp. nov. is known only from a
handful of individual plants in one location near Nangade, making it “Critically
Endangered” (CR) following IUCN Red List categories and criteria.
MOTS CLÉS
Cabo Delgado,
espèce nouvelle,
systématique,
rivière Rovuma,
danger critique
d’extinction.
RÉSUMÉ
Une nouvelle espèce d’Uvaria L. (Annonaceae) du nord du Mozambique.
Uvaria rovumae Deroin & Lötter, sp. nov. est décrite comme nouvelle espèce de
la province de Cabo Delgado (Nord du Mozambique), illustrée et cartographiée.
Sa morphologie, ainsi que ses affinités systématiques, son habitat et son statut
de conservation sont brièvement discutés. Proche, par son port, de Uvaria tanzaniae Verdc., U. rovumae Deroin & Lötter, sp. nov. en diffère principalement
par ses sépales libres, ses pétales internes un peu onguiculés et ses carpelles plus
nombreux (>35). Ce taxon n’est représenté que par un petit nombre d’individus
sur une seule dition près de Nangade, et peut être considéré « en danger critique
d’extinction » (CR) selon les catégories et critères de la Liste rouge de l’UICN.
ADANSONIA, sér. 3 • 2013 • 35 (2) © Publications Scientifiques du Muséum national d’Histoire naturelle, Paris.
www.adansonia.com
227
Deroin T. & Lötter M.
INTRODUCTION
With c. sixteen recognized species, Uvaria L. is
the largest genus in the family for the tropical
East African flora, but its taxonomy remains imperfectly known (Robson 1960; Verdcourt 1971;
Johnson et al. 1999). Taxonomic difficulties in the
group may, at least in part, be due to a complex
biogeographical history during the Oligocene
or Early Miocene, involving both Africa and
Madagascar, changes in sea currents and fruit
dispersal by primates, as recently demonstrated
by Zhou et al. (2012).
Uvaria rovumae Deroin & Lötter, sp. nov.,
was first collected by one of us (Mervyn Lötter) in March 2009 during a plant survey in
Cabo Delgado province (northern Mozambique). A collection of a fruiting specimen was
made, which ML provisionally referred to as
Uvaria tanzaniae Verdc., but suspected to be
a new species. ML returned to the site again
in January 2012 and collected flowering material, which was sent to the senior author who
confirmed that it was indeed an undescribed
species.
MATERIAL AND METHODS
Two collections – one flowering, the other
fruiting – were made from the same locality,
two years apart. As usual for the family, flowers were rather sparse on the twigs, and thus
a single flower – a little time before the anthesis (Fig. 1E) – was available on the isotype
deposited at P. This was then rehydrated and
restored in NH4OH 10%aq. at 60°C, fixed in
FAA and dissected in the usual preservative
(Alcohol-Water-Glycerol, at equal volumes).
Each stage of the dissection was drawn, and
all floral members were mounted on slides and
filed with the isotype sheet kept at P herbarium.
Examination of a dried mature fruit was found
to be enough for the description.
Several photographs taken on the field were
available, allowing a correct interpretation of
floral and fruit morphology.
228
SYSTEMATICS
Uvaria rovumae Deroin & Lötter, sp. nov.
(Figs 1; 3; 5)
Species habitu cum Uvaria tanzaniae Verdc. valde congruens,
sed foliis non hirsutis subtus, pedicellis non obsoletis, calyce
non cupuliformi sesquilatiori cum sepalis omnino liberis,
petalis ellipticis vs. ovatis, neque tomentosis, plusminusve
sesquilongioribus, intimis leviter unguiculatis, carpellis
numerosissimis cum ovulis c. 10 vs 20 biserialibus, mericarpis
nullo modo fusiformibus 2 vs.10-seminatis praecipue differt.
TYPUS. — Mozambique. Cabo Delgado, Nangade, tall
closed woodland, 11°12’05’’S, 39°38’48’’E, 332 m,
6.I.2012, fl., Lötter 2142 (holo-, BNRH ; iso-, K,
P[P00700917]!).
PARATYPUS. — Mozambique. Cabo Delgado, 16 km south
of Nangade, tall mixed closed woodland forest, 11°12.081’
S, 39°38.796’ E, 332 m, sandy soil, 23.III.2009, fl., Lötter & Turpin 1763 (K, LMA, P[P00700918]!).
ETYMOLOGY. — The specific epithet refers to the nearby
Rovuma River.
DESCRIPTION
Scrambling liana c. 3-4 m tall, young branchlets
rusty stellate-pubescent, later glabrous, pale brown,
sparsely lenticellate. Leaves held in one plane; leafblades elliptic or obovate, 55-126 × 27-61 mm, obtuse acuminate or emarginate at the apex, rounded
or somewhat cordate at the base, papery, densely
pubescent when young, then glabrous above and
beneath except for a few stellate hairs on the midrib
and secondary veins (8-11 pairs), all veins slightly
printed above, prominent beneath; petiole 3-6 mm
long, stellate-pubescent.
Inflorescence leaf-opposed, peduncle c. 7 mm
long, flowers 1(-2); bracteoles 2, c. 10 × 6.5 mm,
pubescent outside, lower bracteole rounded slightly
unguiculate, upper one elliptic. Torus as a depressed cylinder c. 14 mm in diameter, flat convex
above. Perianth members basically with 5 primary
nerves and a dense brochidodromous venation.
Sepals broadly ovate, c. 11 × 15 mm, obtuse, free,
pubescent outside, pale green. Petals subequal,
gold yellow with a greenish tinge, apex obtuse or
rounded, spreading, reflexed at the end of anthesis, the outer elliptic c. 18 × 11.5 mm, sparsely
pubescent outside, the inner narrowly elliptic with
ADANSONIA, sér. 3 • 2013 • 35 (2)
A new Uvaria L. species (Annonaceae) from Mozambique
P
K
L
M
Q
R
N
D
A
O
B
E
C
J
I
F
G
H
Fig. 1. — Uvaria rovumae Deroin & Lötter, sp. nov.: A, flowering twig; B, C, leaves (abaxial side); D, detail of the middle of leaf-blade,
with domatia; E, flower just before the anthesis; F,G, lower and upper bracteoles; H, sepal; I, J, outer and inner petal; K-M, stamen,
in abaxial, side and adaxial views; N, outer stamen, adaxial view; O, receptacle and gynoecium; P, Q, carpel in abaxial and adaxial
views; R, carpel in longitudinal section. Lötter 2142 (iso-, P). Drawing Thierry Deroin. Scale bar: A-C, E, 1 cm; D, 1 mm; F-J, O, 5 mm;
K-N, P-R, 2 mm.
ADANSONIA, sér. 3 • 2013 • 35 (2)
229
Deroin T. & Lötter M.
Fig. 2. — Uvaria rovumae Deroin & Lötter, sp. nov.: two inner
petals congenitally fused. Lötter 2142 (iso-, P). Drawing Thierry
Deroin. Scale bar: 5 mm.
a broad claw c. 20 × 11 mm, glabrous outside. Stamens numerous (c. 300, arranged in 6-7 whorls),
linear c. 2 × 0.6 mm, latrorse, connective head
truncate and minutely papillose, enlarged above
narrow pollen sacs. The outermost stamens more
rounded, c. 1.5 mm long. Carpels slender, c. 50,
ovary c. 2 mm long, with scattered stellate hairs
on the abaxial side, ovules c. 10, biseriate; stigmas
horseshoe convoluted c. 0.5 mm thick, covered
with simple hairs.
Fruit a pseudosyncarp ellipsoid in outline, c.
45 mm in diameter and 30 mm tall, pale yellow,
borne on a peduncle c. 12 mm long and 3 mm
thick, sepals persistent reflexed but not accrescent, mericarps c. 50 obovoid and apically rostrate, covered by sparse stellate hairs, 13-18 mm
long, crowded on a globular receptacle by very
short stipes (2 mm or less). Seeds 2 per mericarp,
ellipsoid-irregular c. 6-8 × 4 × 4 mm, with a glossy
reddish brown testa showing a weak pattern of
endosperm rumination.
DISTRIBUTION, ECOLOGY AND PHENOLOGY
Uvaria rovumae Deroin & Lötter, sp. nov., appears to be a range-restricted species, hitherto
only recorded from the dense understory of a
single large Newtonia paucijuga (Harms) Brenan
tree, about 25 km south of the Rovuma River
230
near Nangade, 63 km north of Mueda (Fig. 4).
The surrounding vegetation was once probably
tall semi-deciduous closed woodland or dry
deciduous forest, but this has now largely been
transformed to a mosaic of open to closed semideciduous woodland with isolated small patches
of semi-deciduous forest. Forty-five years ago,
Wild & Barbosa (1967) classified the vegetation in this area as Dry deciduous Lowland Forest. Our new species now only occurs in one of
the very small remnant forest/thicket patches.
Some of the associated woody species occurring
with Uvaria rovumae Deroin & Lötter, sp. nov.,
include: Newtonia paucijuga, Bombax rhodognaphalon K.Schum. ex Engl., Millettia stuhlmannii
Taub., Strychnos myrtoides Gilg & Busse, Vismianthus punctatus Mildbr., Whitfieldia orientalis
Vollesen, Rinorea welwitschii (Oliv.)Kuntze subsp.
tanzanica Grey-Wilson, and Streblus usambarensis
(Engl.) C.C.Berg.
Floral biology (Fig. 3B-D) conforms to the pattern typical of Uvaria: no pollination chamber
(Saunders 2009: 578) and strict protogyny, with
at first a receptive stigmatic plate covered by a
mucilaginous cap (Fig. 3B) then a release of pollen
grains (Fig. 3D).
CONSERVATION STATUS
After several botanical surveys in the region, this
new species appears to be restricted to only one
very small patch of forest undergrowth in an area
to the north Nangade and just south of Mecabua
village. This same locality harbours several other
species of considerable biogeographic interest, such
as two new records for Mozambique; Whitfieldia
orientalis (Lötter & Turpin 1764); and Rinorea welwitschii subsp. tanzanica (Violaceae) (Burrows &
Burrows 11314). It is also the second only locality
of Streblus usambarensis (Moraceae) (Burrows &
Burrows 11313) for Mozambique. An undescribed
species of Lagynias E.Mey. (Rubiaceae) (Burrows &
Burrows 11316) was also found in the same forest
patch. The habitat of the first record of the Streblus
usambarensis for Mozambique is classified by Wild
& Barbosa (1967) as Dry Deciduous Lowland Forest, supporting our opinion that this area was once
much more heavily forested.
ADANSONIA, sér. 3 • 2013 • 35 (2)
A new Uvaria L. species (Annonaceae) from Mozambique
A
B
C
D
Fig. 3. — Uvaria rovumae Deroin & Lötter, sp. nov., flower morphology: A, floral bud, note the leaf-opposed position; B, C, flower at
the ♀ stage, by side and above, petals are spread out; D, flower at the ♂ stage, petals are strongly reflexed, pollen (white) is released
by browning dislocating stamens (field photographs Mervyn Lötter).
The current site is dependent on the shade
from a single large Newtonia paucijuga tree. The
logging of this tree would allow light and fire to
penetrate this biogeographically important forest patch. A large road running southwards from
Nangade to Mueda cuts through part of this once
larger forest patch. We suspect that more plants of
Uvaria rovumae Deroin & Lötter, sp. nov., may
eventually be found in the Rovuma River valley,
or even in southern Tanzania. However it is currently only known from less than 5 individuals
ADANSONIA, sér. 3 • 2013 • 35 (2)
in an area no more than 30 × 30 m. Based on the
IUCN Red List categories and criteria version 3.1
(IUCN 2001), a provisional conservation status
of Critically Endangered CR B1ab(iii); C1; D1
is thus proposed.
MORPHOLOGICAL REMARKS
The dissected flower of Uvaria rovumae Deroin &
Lötter, sp. nov., showed two puzzling features:
1) Two of the three inner petals were accidentally
connate, as demonstrated by the merging of the
231
Deroin T. & Lötter M.
38°E
39°
40°
41°
42°
8°S
Indian
Ocean
9°
TANZANIA
10°
11°
12°
13°
MOZAMBIQUE
14°
15°
Fig. 4. — Map showing the known distribution of Uvaria rovumae
Deroin & Lötter, sp. nov.
most lateral veins (Fig. 2). A basal fusion of petals
was previously reported in some species of the genus
(van Heusden 1992: 150), but did not involve the
primary vasculature.
2) Some of the most outer stamens are shorter
and rounded (Fig. 1N), rather reminiscent of staminodes, frequent in Annonaceae (Saunders 2009:
584) and usually present in several – especially
Asiatic –Uvaria species (van Heusden 1992: 150),
although they are here fertile.
Uvaria rovumae Deroin & Lötter, sp. nov. resembles members of the Uvaria angolensis group,
as expanded by Johnson et al. (1999), in that its
petals become strongly revolute during anthesis,
but differs markedly by its free sepals and more
numerous carpels (>35).
232
If the cupuliform calyx is not considered, U. rovumae appears intermediate between the two
subgroups (U. tanzaniae Verdc. + U. angolensis
Oliver) and (U. lucida Bentham + U. puguensis
D.M. Johnson), being similar to the first in habit
and petal size, much more to the second by the
scattered pubescence of flowers. The similarity is
striking with U. puguensis, especially in the torus
morphology (Johnson et al. 1999; Fig. 2E) and
petal colour (“yellow-green to pale orange-yellow”),
as well as trichome, but the flower is much smaller
(torus c. 5 vs 14 mm diam.), exhibiting a low stamen
number (30-40 vs 300) with stretched quadrate vs
truncate head connectives.
In their phylogenetic reconstruction of Uvaria,
Zhou et al. (2012: 325) show that all African
and Malagasy species are in a same clade II,
splitting off during the Miocene, at c. 17.0 Ma.
It is noteworthy that sepals are usually free or
slightly connate at the base in Malagasy species (Cavaco & Keraudren 1958: 7; Deroin &
Gautier 2006), as in U. rovumae. A cupuliform
calyx is a good character in an identification key,
but cannot be used for outlining natural units.
Perhaps is it possible to explain the free sepals
of U. rovumae by a shift in the gene expression
during floral morphogenesis (Saunders 2009:
586). The synsepaly character, expected in this
species-group, tends to be then expressed more
inside in the perianth, while outer stamens are
coming close to staminodes. It is possible that
the increase of stamen and carpel numbers is
correlated.
The pseudosyncarpic fruit (Fig. 5) is similar
to that of Uvaria scabrida Oliv., a West African
species (Le Thomas 1969: 77). It is noticeable
that in both species almost no carpel abortion
occurs during fruit set. However in U. scabrida
the floral receptacle is already globular, while in
U. rovumae Deroin & Lötter, sp. nov. it appears
flattened. On the other hand, if compared with
the related U. tanzaniae Verdc., only 20% of the
ovules evolve in mature seeds and so the mericarps
are not fusiform and even very slightly lomentaceous (Verdcourt 1986: 287). These structural
differences entail likely divergences in dispersal
biology between these close species.
ADANSONIA, sér. 3 • 2013 • 35 (2)
A new Uvaria L. species (Annonaceae) from Mozambique
A
B
Fig. 5. – Uvaria rovumae Deroin & Lötter, sp. nov.: details of fruit. A, fruiting twig; B, cross section of the pseudosyncarp, Lötter &
Turpin 1763 (field photographs Mervyn Lötter).
ADANSONIA, sér. 3 • 2013 • 35 (2)
233
Deroin T. & Lötter M.
Acknowledgements
We would like to thank John Burrows for comments
on the earlier manuscript and Quentin Luke for
views on the taxonomy of Uvaria rovumae Deroin &
Lötter, sp. nov.. We would also like to acknowledge Pro-Natura International and the Muséum
national d’Histoire naturelle in Paris, who kindly
contributed financial support towards the March
2009 botanical expedition in Cabo Delgado Province. The National Herbarium (LMA), Instituto de
Investigação Agrária de Moçambique, are gratefully acknowledged for supporting our botanical
exploration in Mozambique and for the necessary
collecting permits. The Mpumalanga Tourism &
Parks Agency are thanked for allowing the second
author time off to participate in the botanical survey in Mozambique.
We also wish to thank Jonathan Timberlake, and
an anonymous reviewer for constructive comments
and suggestions.
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Submitted on 6 September 2012;
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published on 27 December 2013.
234
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