Free-living bryozoans (Cheilostomatida, Cupuladriidae) from northeastern and northern Brazil
Author
Almeida, Ana C. S.
Author
Souza, Facelucia B. C.
Author
Vieira, Leandro M.
0000-0001-8661-8861
leandro. mvieira @ ufpe. br; leandromanzoni @ gmail. com; https: // orcid. org / 0000 - 0001 - 8661 - 8861
leandro.mvieira@ufpe.br
text
Zootaxa
2021
2021-02-18
4933
1
39
62
journal article
8068
10.11646/zootaxa.4933.1.2
52c17d8b-7a5a-4f54-9375-2512105d1ea4
1175-5326
4547928
123B1BD8-BD38-4139-8782-EFA2BB07E084
Discoporella salvadorensis
Winston, Vieira & Woollacott, 2014
(
Figs 8
,
9
;
Table 2
)
Discoporella salvadorensis
Winston, Vieira & Woollacott, 2014
: p. 162
, fig. 14.
Discoporella umbellata
var.
conica
:
Marcus & Marcus, 1962
: p. 304
, pl. 5, figs 23–25;
Braga, 1967
: p. 9.
?
Discoporella umbellata
var.
conica
Canu & Bassler, 1930: p. 12
.
?
Discoporella umbellata
:
Tommasi, 1967
: p. 51
(in part);
Tommasi
et al.
, 1972
: p. 139 (in part).
Discoporella conica
:
Migotto
et al
., 2011
: p. 268
.
Discoporella salvadorensis
:
Souza & Almeida, 2017
: p. 265
.
Material examined.
UFBA
1496.1, BA (Abrolhos Archipelago), 2 colonies;
UFBA
182.3, BA (Ilhéus-Porto Seguro), 6 colonies;
UFBA
2577.2, BA (Cairu), 6 colonies;
UFBA
2245.2,
UFBA
2613.2, BA (Maraú), 10 colonies;
UFBA
168.2,
UFPE
540, BA (off Baía de Todos os Santos), 10 colonies;
UFBA
749.1,
UFBA
751.1,
UFBA
754.1, BA (Baía de Todos os Santos), 6 colonies;
UFBA
162.2,
UFBA
164.2, BA (
Salvador
), 12 colonies;
UFBA
002.1,
UFBA
004.1,
UFBA
018.1,
UFBA
021.1,
UFBA
022.1,
UFBA
023.1,
UFBA
651.2,
UFBA
855.1,
UFBA
857.1,
UFBA
1484.2,
UFBA
2479.1,
UFBA
2738.2,
UFBA
2743.1,
UFPE
541,
UFPE
542, BA (Camaçari), 83 colonies;
MOUFPE
64-Akaroa130,
MOUFPE
69.2-Akaroa122, SE (Pirambu), 5 colonies;
MOUFPE
42.3-Akaroa139, SE (Aracaju), 1 colony;
MOUFPE
34.2-Akaroa152,
MOUFPE
40.3-Akaroa154, SE (Itaporanga d’Ajuda), 3 colonies;
UFPE
531, RN (Guamaré), 3 colonies;
MOUFPE
10.1-MA13,
MOUFPE
07.3-MA14, MA (Cedral), 5 colonies;
MOUFPE
23.1-MA24,
MOUFPE
18.2-MA27,
MOUFPE
35.3-MA41, PA (Bragança), 5 colonies;
MOUFPE
17.3- MA34, PA (S„o Jo„o de Pirabas), 2 colonies;
MOUFPE
36.1-MA38, PA (Algodoal), 2 colonies;
MOUFPE
25.1- MA39, PA (Salinópolis), 1 colony;
MOUFPE
28.1-MA49, PA (
Ilha
do Mosqueiro), 1 colony;
MOUFPE
02.3-MA56,
MOUFPE
03.3-MA62,
MOUFPE
05.3-MA60,
MOUFPE
22.3-MA59,
MOUFPE
24.3-MA68, AP (Macapá), 7 colonies;
MOUFPE
27.1-MA65, AP (Araguari River Mouth), 6 colonies.
Description.
Colonies dome-shaped (
Figs 8A
;
9A, B
),
2.1–5.2 mm
in diameter (mean
2.5 mm
; n = 30; standard deviation
0.7 mm
). Central area of colony formed by oval to lozenge-shaped autozooids occluded by secondary calcification, with minute central and lateral frontal openings (
Figs 8A, B
;
9A, C
). Autozooids lozenge-shaped, separated by elevated lateral walls, with a D-shaped to oval opesia (
Figs 8C
;
9D
). Cryptocystal shield granular, occupying roughly three-fifths of opesia length, with 4–6 irregularly shaped opesiules sometimes partly occluded by spinous processes. Gymnocyst narrow, evident as a raised rim around autozooid. Vicarious heterozooid lozengeshaped; opesia oval, occupying more than half of zooidal length; with crenulate margin, cryptocyst granular, wider laterally and proximally; gymnocyst evident as a narrow, raised rim around avicularium (
Figs 8C
;
9A, C
). Vibracular chamber subtriangular to C-shaped, located distal to each autozooid and avicularium; opesia auriform; paired and hooked mediolateral flanges; cryptocyst granular, narrow but widest proximally; wide band of smooth gymnocyst evident laterally (
Figs 8D
;
9D
). Colonies with ceased growth have kenozooids (see arrows in
Fig. 9B, F
) between autozooids but with some openings remaining and vibracula still functional at colony margin. Basal surface almost smooth, with slight traces of radial grooves and without obvious granules (
Fig. 8D
).
Remarks.
Marcus & Marcus (1962)
characterized two colony morphologies among
Discoporella
specimens from several localities in
Brazil
: discoidal (flat and thin) and dome-shaped (thick). Discoidal specimens attributed by
Marcus & Marcus (1962)
to
D. umbellata
are now accepted as
D. gemmulifera
, as discussed above. Specimens of the second
type
, with dome-shaped colonies, were assigned to
D. umbellata
var.
conica
(Canu & Bassler, 1930)
. Canu & Bassler (1930) briefly mentioned the fossil form
Cupularia umbellata
var.
conica
from the middle Miocene (Helvetian) of Touraine,
France
, but provided no description or figures. Both the
type
locality and stratigraphic occurrence of
D. umbellata
var.
conica
suggest that the nominal species is different from specimens found in the Recent Brazilian fauna.
Winston
et al
. (2014)
described
D. salvadorensis
from a single specimen from
Bahia
, characterizing it as having a dome-shaped colony, 4–6 opesiules, and a triangular to C-shaped vibracular opesia, with determinate colony growth marked by calcified kenozooids. These authors concluded that their specimen was very different from material studied by
Marcus & Marcus (1962)
, and compared their new species with
D. gemmulifera
(=
D. umbellata sensu
Marcus & Marcus 1962
). The specimen described by
Winston
et al
. (2014)
resembles specimens of
D. umbellata
var.
conica
described and figured by
Marcus & Marcus (1962)
in all morphological characters, including the colony morphology, opesia, number of opesiules, vibracular chamber and kenozooids. Zooidal measurements are also similar: autozooids
0.216
–0.324
mm
long by
0.180
–0.234
mm
wide in specimens described by
Winston
et al
. (2014)
;
0.2–0.4 mm
long by
0.15–0.25 mm
wide in specimens characterized by
Marcus & Marcus (1962)
. The only difference between the specimens is in the degree to which marginal autozooids are closed by secondary calcification. In more than 150 colonies examined from
Bahia
, we found that kenozooids are not constantly present in all colonies with ceased growth, and that this feature can vary even within the same colony (
Fig. 9E, F
). We thus reassign specimens identified by
Marcus & Marcus (1962)
as
D. umbellata
var.
conica
to
D. salvadorensis
.
Marcus & Marcus (1962)
described different astogenetic stages in
D. salvadorensis
(as
D. umbellata
var.
conica
)—young colonies, which are short and conical, with the margin bearing projecting vibracular chambers, and older colonies that have ceased growth, which are larger and higher, with autozooids closed by secondary calcification and kenozooids occurring at the margin (
Marcus & Marcus 1962
: pl. 5, fig. 25). We observed these same morphologies among our specimens, representing either young colonies (
Fig. 8
) or older colonies (
Fig. 9
).
Besides
D. gemmulifera
and
D. salvadorensis
, two other species have been recorded along the Brazilian coast:
D. umbellata
and
D. depressa
(
Conrad, 1841
)
(
Tommasi 1967
;
Tommasi
et al.
1972
;
Buge 1975
;
Winston & Migotto 2005
;
Migotto
et al
. 2011
;
Almeida
et al
. 2015a
;
Souza &Almeida 2017
). Specimens from S„o Sebasti„o (S„o Paulo) (
Winston & Migotto 2005
;
Migotto
et al
. 2011
) are here referred to
D. gemmulifera
. Other specimens from S„o Paulo and
Rio de Janeiro
studied by
Tommasi (1967)
and
Tommasi
et al.
(1972)
that are deposited in the Bryozoa collection of the MZUSP (L.M. Vieira, unpublished data) need to be reexamined; the presence of two colony forms in some of the samples suggest these specimens may represent both
D. gemmulifera
and
D. salvadorensis
.
FIGURE 8.
Discoporella salvadorensis
Winston, Vieira & Woollacott, 2014
. A–D. UFBA 857.1, growing colony. A. Colony frontal view with vicarious heterozooid indicated by arrows. B. Autozooids in the central area of the colony and vicarious heterozooid (top left). C. Detail of vicarious heterozooid. D. Detail of vibracular chambers. E. Marginal autozooids with projecting vibracular chambers. F. Colony basal view. Scale bars: A, B. 500 µm; C. 100 µm; D, E, F. 200 µm.
FIGURE 9.
Discoporella salvadorensis
Winston, Vieira & Woollacott, 2014
. A–D. UFBA 2613.2, colony with ceased growth. A. Colony frontal view. B. Colony lateral view (kenozooids indicated by arrows). C. Autozooids in the central area of the colony and a group of vicarious heterozooid (arrow). D. Group of autozooids and its vibracular chambers. E. Marginal autozooids. F. Marginal kenozooids (arrows). Scale bars: A, B. 1 mm; C. 500 µm; D, E, F. 300 µm.
Discoporella salvadorensis
differs from
D. gemmulifera
in having dome-shaped colonies (bowl-shaped in
D. gemmulifera
), 4–6 frontal opesiules (6 or more in
D. gemmulifera
) and determinate colony growth (semi-determinate in
D. gemmulifera
) (
Winston & Vieira 2013
). The main differences between
D. umbellata
and
D. salvadorensis
include the colony morphology (flat, up to
22 mm
in diameter in
D. umbellata
; dome-shaped, up to
5.2 mm
in diameter in
D. salvadorensis
), autozooidal opesia (with paired denticles on the proximal margin in
D. umbellata
; denticles absent in
D. salvadorensis
) and number of opesiules (
8–14 in
D. umbellata
;
4–6 in
D. salvadorensis
) (
Cook 1965a
;
Herrera-Cubilla
et al
. 2008
). Differences between
D. depressa
and
D. conica
include the colony morphology (flat, up to
18 mm
in diameter in
D. depressa
; dome-shaped, up to
5.2 mm
in diameter in
D. conica
), number of opesiules (
3–9 in
D. depressa
;
4–6 in
D. conica
) and basal surface (tuberculate and with conspicuous grooves in
D. depressa
; without obvious granules or conspicuous grooves in
D. conica
) (
Cook 1965a
). According to
Di Martino
et al.
(2017)
, a revision of all specimens assigned to
D. depressa
is needed, since several taxa may be involved. This likely applies as well to the Brazilian records by
Buge (1975)
and
Cook (1965a)
.
Among congeners,
D. salvadorensis
most resembles
D. cookae
Herrera-Cubilla, Dick, Sanner & Jackson, 2008
and
D. triangula
Herrera-Cubilla, Dick, Sanner & Jackson,
2008
in having dome-shaped colonies (
Herrera-Cubilla
et al
. 2008
).
Discoporella salvadorensis
differs from
D. cookae
in having colonies with a maximum diameter of
5 mm
(
10.8 mm
in
D. cookae
), determinate growth (semi-determinate in
D. cookae
), 4–6 opesiules (
7–9 in
D. cookae
), kenozooids (absent in
D. cookae
), and the basal surface without obvious granules or conspicuous grooves (with high density of granules and distinct radial grooves in
D. cookae
) (
Herrera-Cubilla
et al
. 2008
).
Discoporella conica
and
D. triangula
differ in the size of the colony (maximum diameter
5.2 mm
in
D. salvadorensis
,
3.9 mm
in
D. triangula
), number of opesiules (
4–6 in
D. conica
;
5–9 in
D. triangula
) and basal surface (without obvious granules in
D. salvadorensis
; with conspicuous granules in
D. triangula
) (
Herrera-Cubilla
et al
. 2008
).
Distribution.
Western Atlantic:
Brazil
(
Paraná
, S„o Paulo,
Rio de Janeiro
,
Bahia
,
Sergipe
,
Rio Grande do Norte
, Maranh„o,
Pará
and
Amapá
) (
Marcus & Marcus 1962
;
Braga 1967
;
Winston
et al
. 2014
; present study).