Taxonomic Revision of Coleostachys (Malpighiaceae)
Author
Almeida, Rafael Felipe De
Universidade Estadual de Feira de Santana, Departamento de Ciências Biológicas, Programa de Pós-Graduação em Botânica, Avenida Transnordestina s / n, Novo Horizonte, CEP 44036 - 900, Feira de Santana, Bahia, Brazil.
Author
Hall, Climbiê Ferreira
Museu Paraense Emílio Goeldi, Campus de Pesquisa, Coordenação de Botânica, Programa de Capacitação Institucional, Av. Perimetral, Terra Firme, CEP 66077 - 830, Belém, Pará, Brazil
text
Phytotaxa
2016
2016-09-23
277
1
77
84
http://dx.doi.org/10.11646/phytotaxa.277.1.7
journal article
10.11646/phytotaxa.277.1.7
1179-3163
13646544
Coleostachys genipifolia
Jussieu (1840: 329)
.
Type
:—
FRENCH GUIANA
: Cayenne.,
s.d.
,
Martin
s.n.
(
holotype
:
P
barcode
P02428718
!;
isotypes
: BR barcode BR0000008577450!, F barcode V0062669F!, K barcode K000427026!, MICH barcode MICH1102137!, P barcodes P02428719!, P02428720!, P02428721!, P-JU barcode P00671745!,
RB
barcode 540728!).
Fig. 1–4
.
FIGURE 1.
Coleostachys genipifolia
: A. Habit, B. detail of the leaf and inflorescence, C. detail of the inflorescence axis, D. detail of a flower bud, E. detail of a flower (photos by A. Cardoso).
FIGURE 2.
Coleostachys genipifolia
: A. fruiting branch, B. detail of a inflorescence, C. floral bud in lateral view, D. flower in frontal view, E. detail of a stamen, F. gynoecium, G. detail of a cocci (MG202875).
FIGURE 3.
Holotype of
Coleostachys genipifolia
.
Shrubs or treelets,
1.5–4 m
tall, growth monopodial. Stems rugose, tomentose, hairs brown. Leaves decussate, entire, not reduced in inflorescences; stipules 1.8–2.2 ×
4.7–5 mm
, intrapetiolar, connate, deciduous, leaving a scar on stems; petioles
15.5–40 mm
long, cylindrical, eglandular, sericeous to glabrescent at age, hairs brown; blades 29–59.5 ×
6.5– 11.3 cm
, plane, oblanceolate to spatulate, base acute to attenuate, margin plane; apex acuminate, adaxially glabrous, abaxially sericeous only along the veins, eglandular; venation brochydodromous, primary veins adaxially impress, abaxially prominent, secondary veins 29–32 pairs, proximally opposite, distally alternate, adaxially impressed, abaxially prominent, tertiary veins adaxially inconspicuous, abaxially conspicuous. Spikes axillary to terminal; main axis
9.5–22.7 cm
long, cylindrical, smooth to striated, tomentose, basal node bearing 1-pair of stipule-like bracts,
1.5–4 cm
long, smooth, sparsely sericeous to glabrous, enclosing apex of shoots before elongation; cincinni 16–33, cincinni 1-flowered, proximally opposite, distally subopposite; bracts 5–7 ×
4–4.5 mm
, ovate, sessile; apex acute, tomentose, eglandular; peduncles sessile; bracteoles 2–3 ×
1.5–2 mm
, ovate, sessile; apex rounded, tomentose, eglandular. Flowers
11.3–15 mm
diam., floral buds 4–7 ×
3–6 mm
, obovoid to sub-globose; sepals not concealing petals in floral bud, 4–5 ×
3–4 mm
, ovate, shortly connate at base, margin repand, apex rounded, adaxially glabrous, abaxially sericeous; hairs brown, eglandular; petals white, cucullate, margin erose; posterior petal erect, limb 7.5–8 ×
8.5–9 mm
, depressed ovate, adaxially glabrous, abaxially sericeous centrally; claws 2.5–3 ×
0.8–1 mm
, canaliculate, adaxially glabrous, abaxially sericeous; lateral petals patent, limb 6–7 ×
6–7.5 mm
, widely ovate, adaxially glabrous, abaxially sericeous centrally; claws 2.5–3 ×
0.5–0.6 mm
, canaliculate, adaxially glabrous, abaxially sericeous. Stamens 10, all fertile, free; filaments
2.5–3.2 mm
long, whitish, arched at apex, densely tomentose at base; hairs straight-basifixed; connectives very reduced and inconspicuous; anthers yellow, linear-lanceolate to lanceolate, apex acute, base cordate, locules 3.5–5.5 ×
1.2–1.5 mm
; pollen sacs parallel, sparsely sericeous, dehiscing by 1 apical pore. Ovary 3-carpelate, free, all fertile, 1.5–1.8 ×
0.5–0.8 mm
, hirsute; styles 3, 5–7.5 ×
0.2–0.35 mm
, slightly bent inwards, subulate, basal, whitish; stigma apical, subulate. Schizocarp composed by 3 un-winged mericarps (cocci), borne on a flat torus; cocci 6–12 ×
5–8 mm
, subspheroidal, tapered towards the areole, smooth, indehiscent, thin-walled, brittle; areole 2–2.5 ×
0.9–1 mm
, piriform. Seeds
7–8 mm
×
5–6 mm
, sub-globose, flattened; embryo bent inwards.
Specimens analyzed:—
BRAZIL
.
Amapá
:
sin. loc.
,
17 November 2011
, fl.,
Bastos
263
(
IAN
,
RB
).
Maranhão
:
Vila Rondon
,
14 August 1976
, fl.,
Pinheiro
65
(
IAN
).
Pará
: Alto
Rio Capim
,
26 March 1949
, fl.,
Fróes
24147
(
IAN
)
;
Candirú-Açú
,
28 August 1957
, fl.,
Fróes
33618
(
IAN
)
;
Ilha do Breu
,
19 September 1987
, fl.,
Prance
1353
(
IAN
,
NY
)
;
Moju
,
4 November 1923
, fl.,
Ducke
228
(
P
)
;
loc. sit.
,
Juruá Florestal
,
22 October 2001
, fl.,
Martins
13
(
IAN
)
;
Paragominas
,
1 December 2010
, fl.,
Oliveira
573
(
IAN
)
;
Parauapebas
,
Serra
dos
Carajás
,
19 December 1989
, fr.,
Rosa
637
(
IAN
)
;
Região do Candirú-Açú
,
Rio Capim
,
28 August 1957
, fl.,
Fróes
33618
(
IAN
)
;
Rio Capim
,
25 March 1949
, fl.,
Fróes
24121
(
IAN
)
;
Rio Moju
,
16 April 1957
, fl.,
Fróes
33922
(
IAN
)
;
loc. sit.
, lugar
Fábrica
,
1 December 1955
, fl.,
Pires
4593
(
IAN
)
;
loc. sit.
,
December 1953
, fl.,
Pires
4583
(
IAN
)
;
São Domingos do Capim
,
25 November 1980
, fl.,
Ramos
736
(
INPA
)
;
São Miguel do Guamá
, km 149
Belém-Brasília Road
,
26 January 1960
,
Oliveira
422
(
IAN
)
;
Serra dos Carajás
,
28 June 1976
, fl.,
Ribeiro
1395
(
IAN
)
;
Tailândia
,
20 January 2011
, fr.,
Costa-Neto
2985
(
MFS
,
MG
)
;
loc. sit.
,
20 January 2011
, fl.,
Costa-Neto
2967
(
MG
)
;
Tomé-Açú
,
1 January 1978
, fl.,
Nascimento
385
(
MG
)
;
loc. sit.
,
22 October 1979
, fr.,
Silva
5073
(
MG
)
;
Tucuruí
,
19 June 1978
, fl.,
Rosa
2424
(
IAN
,
MG
)
;
loc. sit.
,
14 November 1968
, fl.,
Daly
1331
(
IAN
,
INPA
,
MG
,
NY
)
;
Ulianópolis
,
1 December 2000
, fl.,
Secco
1089
(
MG
)
.
Distribution, ecology and phenology:—
Coleostachys genipifolia
grows in the understory of lowland forests (“terra firme” forests) of Eastern Amazon in
Brazil
(states of
Amapá
,
Maranhão
and
Pará
) and
French Guiana
(
Fig. 4
). Most known collections are from the state of
Pará
in
Brazil
, which might suggest this region is its center of diversity. Flowering occurs from July to April and fruiting in December.
Conservation status:—
Coleostachys genipifolia
has an EOO of
528,403.414 km
² which fits with the IUCN category Least Concern. Nonetheless, when comparing its distribution range to a land use shapefile from state of
Pará
(its center of diversity) it becomes clear that most forest remnants from eastern
Pará
are being converted into farming and livestock land (
Fig. 4
). Biodiversity of the Eastern
Pará state
has been historically threatened by several human activities, such as farming (soybean crops), livestock, logging and mining (especially on Carajás Mountains) (IBGE 2015). All these activities require clearing of the rainforest reducing understory habitats occupied by
C. genipifolia
.
Etymology:—
The genus name
Coleostachys
derives from the Greek words sheath (
koleos
) and spike (
stachys
), due to the resemblance of a sheath of epipetiolar stipules and bracts at the base of spikes (
Anderson
et al.
2006
). The epithet
genipifolia
makes reference to the similarity of its leaves with those of the genus
Genipa
Linnaeus (1754: 87)
,
Rubiaceae
.
FIGURE 4.
Distribution of
Coleostachys genipifolia
in Northern South America, highlighting land use in the state of Pará, Brazil.
Discussion:—
Coleostachys genipifolia
is the single Neotropical genus of
Malpighiaceae
with poricidal anthers. This feature is only known from two Paleotropical
Malpighiaceae
genera,
Acridocarpus
Guillemin & Perrottet (1831: 123)
and
Tristellateia
Thouars (1806: 14)
. Since those genera represent three unrelated lineages of early diverging
Malpighiaceae (
Davis & Anderson 2010
)
, we can assume that poricidal anthers emerged independently at least three different times in the family.
Acridocarpus
and
Tristellateia
are both confined to Africa and
Madagascar
, with a single species of the later also widespread in Southern Asia (
Anderson
et al.
2006
). Their ancestors represent different dispersal events from the Neotropics to the Old Word (
Davis
et al.
2001
;
Davis
et al.
2002a
;
Davis
et al.
2002b
;
Davis & Anderson 2010
), and both diversified at ca. 30 Mya (
Davis
et al.
2014
). Interestingly, the same pattern is observed for
Coleostachys
, with its ancestor starting to diversify at ca. 30 Mya somewhere in the Neotropics (
Davis
et al.
2014
). This scenario leads us to believe that poricidal anthers might probably have emerged in
Malpighiaceae
due to similar selective pressures related to specific pollinators. However, our assertion is merely speculative and only future studies on pollination biology of those genera might shed some light on this question.