“ What’s in a name? ” Bairdia fasciata Brady, 1870, and two new Caribbean species of Bairdoppilata (Bairdiidae, Podocopida, Ostracoda)
Author
Maddocks, Rosalie F.
0000-0002-5486-5072
Department of Earth and Atmospheric Sciences, Room 312 Science & Research Building 1, University of Houston, Houston, TX 77204 - 5007, USA.
RMaddocks@uh.edu
Author
Horne, David J.
0000-0002-2148-437X
School of Geography, Queen Mary University of London, Mile End Road, London E 1 4 NS, UK. & Earth Sciences Department, The Natural History Museum, Cromwell Road, London, SW 7 5 BD, UK.
d.j.horne@qmul.ac.uk
text
Zootaxa
2024
2024-05-13
5448
3
371
400
http://dx.doi.org/10.11646/zootaxa.5448.3.3
journal article
296639
10.11646/zootaxa.5448.3.3
95539a45-2179-477b-875f-3cab2ff0594d
1175-5326
11231896
6907E847-FE33-47AD-9F0A-B8AF763515A8
Bairdiidae
of Other Atlantic Oceanic Islands
Remote oceanic archipelagos have fascinated naturalists since
Darwin (1839)
. Their marine faunas are the result of complex interactions of multiple processes, including dispersal, vicariance, adaptive radiation, production of lecithotrophic vs. planktotrophic larvae, ocean circulation, and geologic history, including volcanism, tectonism, and changes in sea level and temperature. The volcanic and tectonic history of oceanic islands in the North and Central Atlantic is associated with spreading of the Mid-Atlantic Ridge, fracture zones, and mantle plumes or hot spots.
The
Bermuda
platform is an edifice of as much as
200 m
of coral reef limestone, founded on the eroded remnant of an Oligocene intraplate (hot spot) volcano (
Coates
et al.
2013
). It is located on the edge of the Sargasso Sea (
32
o
20’N
,
65
o
45’W
) near the northern limit of hermatypic reef corals, set by the 22
oC
winter isotherm. The
Ostracoda, Foraminifera
and macro-invertebrate communities of Bermuda are of Caribbean derivation, and dispersal via the Gulf Stream is likely. Six bairdiid species in five genera (but no
Bairdoppilata
) were described from modern carbonate sediments by Maddocks & Kornicker (1986),
Maddocks & Iliffe (1986)
,
Keyser & Schöning (2000)
, and
Maddocks (2021
,
2022
). None of the three most abundant Caribbean species of
Bairdoppilata
(
Ba. cushmani
,
Ba. magnafasciata
,
n. sp.
,
Ba. parvafasciata
,
n. sp.
) have reached Bermuda. The Genus
Bairdoppilata
is represented in Bermuda only by three rare species, which have Caribbean affinities.
Madeira
(
33
o
26’N
,
16
o
44’W
) and the
Canary Islands
(
29
o
15’N
,
16
o
30’W
) are ancient hot spot volcanos in the northeastern Atlantic Ocean (
Doniz-Paez
et al.
2020
;
Ramalho 2015
).
Brady (1911)
identified 48 nearshore marine species from Madeira, including
B. acanthigera
among the 5 species of
Bairdiidae
.
Schornikov & Keyser (2004)
described 50 species of
Paradoxostomatinae
, but no
Bairdiidae
, from rocky tide pools and the nearshore zone of Madeira and the
Canary Islands
.
The
Azore
s are volcanic islands located on fracture zones of the Mid-Atlantic Ridge (
25
o
32
’
W
, Long.
37
o
40
’
N
), near a hot spot at the triple junction between the American, Eurasian and African plates (
Gente
et al.
2003
,
Cantner & McFadden 2019
).
Meireles
et al.
(2014a
,
2014b
) described a small ostracod fauna (20 species) from the Azores. It included no
Bairdoppilata
and only one (misidentified) species of
Bairdiidae (
Maddocks 2015
)
.
The
St. Peter and St. Paul Archipelago
of
Brazil
is an uplift of mantle rock exposed in the St. Paul transform fault system of the Mid-Atlantic Ridge (
0
o
55’N
,
29
o
20’43”W
) (
Campos
et al.
2022
). From these wave-swept, algaeencrusted shoals,
Antonietto
et al.
(2012)
and
Coimbra
et al.
(2012)
described 13 species, including 2 species of
Triebelina
and 1 of
Neonesidea
, but no
Bairdoppilata
. All were considered to be circumtropical, and their dispersal was attributed to the Equatorial Current.
Rocas Atoll
(3.863
oS
, 33.806
oW
), the only atoll in the southern Atlantic and one of the smallest in the world), is built on a volcanic seamount,
266 km
from coast of
Brazil
, near the northern edge of the South Equatorial Current (
Garcia
et al.
2022
).
Coimbra & Carreno (2012)
reported 22 species of
Ostracoda
from Rocas Atoll, many in open nomenclature, but no
Bairdoppilata
. The affinities of the identified species were Caribbean or circumtropical.
Trindade Island (
20
o
30’S
,
29
o
18’W
) is an eroded hot spot volcano on the Vitoria-Trindade Fracture Zone, 1,120 0 km from the coast of Brazil (
Monteiro
et al.
2022
).
Coimbra & Carreno (2012)
reported 21 species from Trindade Island, mostly circumtropical or in open nomenclature, but no
Bairdoppilata
.
Ascension Island
is a volcano on the Ascension fracture zone, which offsets the Mid-Atlantic Ridge in the South Atlantic Ocean (
7
o
56’S
,
14
o
22’W
) (
British Geological Survey 2023
). Here, from small faunules collected in tide pools,
Maddocks (1975)
described two species of
Neonesidea
and
Triebelina
(with circumtropical and Mediterranean affinities), as well as two species of
Bairdoppilata
(in open nomenclature, not resembling the species described here).
From the mainland of
West Africa
, there are few records of living
Bairdiidae
, and comparison of the meager faunal lists shows little commonality with island assemblages.
Witte 1993
) described four species of
Bairdiidae
(but no
Bairdoppilata
) from beaches of
Senegal
and
Gambia
.
Keen (1972
, no systematics) reported that
Bairdiidae
make up 15 to 30 percent of the ostracod assemblages at the edge of the continental shelf of
Sierra Leone
.
Hartmann (1974)
described three species of
Bairdoppilata
from
Angola
at Moçamedes (
15
o
10’S
,
12
o
15’E
). The carapace of one of them (
Ba. cytheraeformis
,
see above), shows some resemblance to the Caribbean species
Ba. parvafasciata
.