A new species of Ephesiopsis (Polychaeta: Sphaerodoridae) from off southeastern Brazil
Author
Rizzo, Alexandra Elaine
text
Zootaxa
2009
2307
61
67
journal article
10.5281/zenodo.191800
84ffb6d4-64c5-4b16-9b8f-c14963e40c0e
1175-5326
191800
Ephesiopsis shivae
new species
(
Figures 1–3
)
Type
material
:
MZSP
883 (
holotype
), 24
0 07.637'S
45
0 51.895'W
, 0 9.01.1998, Sta.
6661, 147 m
, Santos/São Paulo to
Ilha
Grande Bay/Rio de Janeiro, collected with dredge;
MZSP
1031 (
paratypes
, 2), 24
0 07.637'S
45
0 51.895'W
, 0 9.01.1998, Sta.
6661, 147 m
, Santos/São Paulo to
Ilha
Grande Bay/Rio de Janeiro, collected with dredge.
Diagnosis
: Macrotubercles with distal papillae. Eyes absent. Chaetae simple, and compound falcigers in all chaetigers. First chaetiger with a pair of falcate hooks. Pygidium with four macrotubercles with terminal papillae.
Description:
Holotype
measuring
20.5 mm
long and
0.9 mm
wide, with 100 chaetigers;
paratypes
are 10 and
16 mm
long, 0.7 and
0.8 mm
wide, and have 49 and 78 chaetigers respectively. All are complete specimens. Two individuals (
holotype
and one
paratype
) with inflated body, filled by large eggs with dark nuclei, apparently in final stage of maturation (
Figures 1−2
E). Body long, slender, with minute epidermal papillae (
Figure 2
A). Prostomium indistinctly fused to peristomium; with two pairs of lateral antennae and a median, papilliform antenna. Median antenna slightly shorter and with larger base than lateral antennae. One small papilla located at base of each lateral antenna. A pair of papilliform peristomial cirri located between lateral antennae and first chaetiger. Several papillae present among the antennae (
Figure 2
B). Eyes absent. Mouth ventro-frontal. Proboscis invaginated, long, cylindrical. Macrotubercles arranged in two longitudinal rows; sessile, rounded, each with a terminal papilla (
Figure 2
C). Microtubercles with narrow bases and elongated distal papillae, slightly larger than terminal papillae of macrotubercles (
Figure 2
D); microtubercles visible mainly on anterior region. Parapodia uniramous and poorly developed, consisting of a conical, distally slender acicular lobe with papillate surface that is slightly longer than the macrotubercles. A single aciculum is present, which may project outwards. Ventral cirrus digitiform, irregular (
Figure 3
A–C). Parapodia of posterior chaetigers rudimentary. Parapodia of chaetiger 1 bear a pair of strong recurved hooks, visible only with light microscopy (
Figure 3
D). Following chaetigers supra-acicular with 3-4 simple chaetae and infraacicular with 1-2 compound falcigers. Simple chaetae have a subdistal protuberance and are distally triangular (
Figure 3
E). Compound falcigers short, with a robust shaft that is distally triangular and spinulate; with ligament extending from end of shafts to lateral bases of distal appendages (
Figure 3
F). Chaetae can be absent from some chaetigers, in particular the median ones. Pygidium with four macrotubercles that bear terminal papillae.
Discussion:
Three specimens of
E. guayanae
were recorded (record
Ch
35 Dr34) and deposited at the Natural History Museum of Los Angeles County; however, this
type
material is probably lost (Salazar- Vallejo, Carrera-Parra & Tovar-Hernandes, pers. com.). This species was first described as
Sphaerodorum
sp. C from off
Brazil
[
sic
], by
Hartman (1965: 96)
. Later, the
type
locality was corrected to off
Guyana
(
Hartman and Fauchald 1971
). The taxon was assigned to the monotypic genus
Ephesiopsis
Hartman and Fauchald 1971
, to contain species having two rows of macrotubercles with terminal papillae, and hooks on the first chaetiger, in addition to simple and compound chaetae on all chaetigers. Two other genera resembling
Ephesiopsis
also have a pair of hooks on the first chaetiger, but they have either simple chaetae on all chaetigers (
Sphaerodorum
) or only compound chaetae (
Ephesiella
), never with both
types
present.
Ephesiopsis shivae
sp. nov.
, differs from
Ephesiopsis guayanae
in having macrotubercles with slightly smaller terminal papillae. The simple chaetae are not as pointed distally as those illustrated by
Hartman and Fauchald (1971: 311)
. Eyes were not observed. In
Ephesiopsis shivae
sp. nov.
, the microtubercles are visible only on the anterior region, but this may result from body modifications because of the number of large eggs inside the body cavity. The posterior region of
E. guayanae
was not mentioned in the original description, although the
holotype
is a complete specimen. It is smaller than the specimens of
E. shivae
sp. nov.
, being
2.2 mm
long and
0.2 mm
wide, with 26 chaetigers. Eggs were not observed in the specimens from
Guyana
.
E. shivae
sp. nov.
also has four macrotubercles with terminal papillae on the pygidium, similar to that of the longitudinal row. Corresponding macrotubercles were not mentioned in the original description of
E. guayanae
,
and it is possible that they are not present in this species.
FIGURE 1.
Ephesiopsis shivae
new species
– Holotype:
A
. anterior and median region, laterodorsal view (scale: 0.5mm).
FIGURE 2.
Ephesiopsis shivae
new species
– Holotype:
A
. Complete specimen, twisted body;
B
. Anterior edge in dorsal view; detail of cephalic appendages, hook and first chaetiger;
C
. Macrotubercle;
D
. Microtubercle between two macrotubercles;
E
. Egg from anterior region, near cephalic appendages. (Abbreviations: Pr—prostomium, v—ventral, h—hook, la—lateral antenna, ma—macrotubercle, par1—first parapodium, vc—ventral cirrus, tp—terminal papilla).
FIGURE 3.
Ephesiopsis shivae
new species
– Holotype:
A
. Parapodium 4;
B
. Parapodium 12;
C
. Parapodium 23;
D
. Hook from first chaetiger;
E
. Simple chaeta;
F
. Compound falcigerous chaeta. (Abbreviations: pa—papilla, vc—ventral cirrus).
Distribution:
Southwestern Atlantic Ocean, off
Brazil
(São Paulo State) at
147 m
depth.
Etimology
: The species is named
shivae
after Shiva, a Siberian husky belonging to the author.