Taxonomy of recent Adeonidae (Bryozoa, Cheilostomata) from Brazil, with the description of four new species
Author
Almeida, Ana C. S.
Author
Souza, Facelucia B. C.
Author
Sanner, Joann
Author
Vieira, Leandro M.
text
Zootaxa
2015
4013
3
348
368
journal article
10.11646/zootaxa.4013.3.2
3821cb3c-e6c6-4e74-9b0f-df7bd7ee75af
1175-5326
237289
C0B220BE-ADD6-4D07-B416-F849D96DCFA6
Reptadeonella costulata
(
Canu & Bassler, 1928a
)
(
Figs 10–12
;
Table 1
)
Adeona costulata
Canu & Bassler, 1928a
: 37
, pl. 8, figs 7–8. [
Brazil
: Rio de Janeiro]
Reptadeonella costulata
:
Vieira
et al.
2008
: 24
. [
Brazil
; checklist]
Material examined.
Holotype
:
USNM
8570,
Adeona costulata
, F. Canu & R. Bassler
det., Rio de Janeiro,
Brazil
,
128 m
, coll. 1877 by Steamer
Norseman
.
Description.
Colony encrusting, multiserial, unilaminar. Zooids more or less elongate-hexagonal to polygonal, longer than wide, delimited by slightly raised margins. Frontal shield heavily calcified, finely granular, marginally punctured by a single row of 22–34 areolar pores. Orifice approximately 16% of total length of frontal shield, mostly slightly elliptical or subcircular, a little wider than long; peristome low, bordered by distal areolar pores. An additional areolar pore, rarely paired, proximal to orifice adjacent to suboral avicularium. Avicularium elongate, more or less latero-oral, placed on frontal shield such that it is directed obliquely past one side of the orifice, the rostral tip almost level with its distal margin; rostrum elongate-triangular, tiny condyles placed one-third length, no opesial cryptocystal shelf. No other frontal avicularia. Spiramen narrower than an arerolar pore, transversely elliptical, placed at midlength of zooid. Gonozooids not recognized.
Remarks.
Reptadeonella costulata
can be distinguished from all congeners by the combination of characters—elongated autozooids with a single row of areolar pores, low peristome, and 1–2 smaller areolar pores adjacent to suboral avicularium that is directed obliquely past the orifice, and tiny elliptical spiramen.
Reptadeonella costulata
is distinguished from
R. bipartita
by the proportionally smaller additional areolar pore (larger in
R. bipartita
), oblique suboral avicularium (straight in
R. bipartita
) and elliptical spiramen (crescentic in
R. bipartita
).
Since its original description,
R. costulata
has been reported from
Jamaica
and
Belize
(
Best & Winston 1984
;
Winston 2005
), but the specimens figured by
Best & Winston (1984)
have a relatively large additional areolar pore (rather than a small elliptical pore as in the
holotype
), a hood-like peristome (low in the
type
specimen) and circular spiramen (transversely elliptical in the
R. costulata
holotype
).
Winston (2005)
measured autozooids in
R. costulata
from the Caribbean as having a mean length of
0.85 mm
and mean width of
0.50 mm
), much larger than in the
type
specimen (mean length
0.57 mm
, mean width
0.29 mm
), and pointed out that the avicularia sometimes extend beyond the distal margin of the orifice, whereas those in the
holotype
are level with distal margin. We conclude that the Caribbean specimens of
R. costulata
(sensu
Best & Winston 1984
) may comprise a distinct species.
Distribution.
Atlantic:
Brazil
(Rio de Janeiro); sublittoral.