Serpulids (Annelida: Polychaeta) from the Eastern Pacific, including a brief mention of Hawaiian serpulids
Author
Bastida-Zavala, J. Rolando
text
Zootaxa
2008
2008-03-07
1722
1
61
journal article
11755334
Spirobranchus incrassatus
Krøyer
[in]
Mörch, 1863
(
Figures 12C–E
)
Spirobranchus incrassatus
Krøyer
[in]
Mörch, 1863: 405
, pl. 11, figs. 21–23.
Type
locality: Western
Colombia
.
Spirobranchus incrassatus
.—
Ehlers, 1887: 294–295
, pl. 57, fig. 16, pl. 58, figs. 1–5, Acapulco (
Guerrero
,
Mexico
).
Spirobranchus giganteus
.—
Bastida-Zavala, 1995: 26–26
, Cabo Pulmo Reef (
Baja California Sur
,
Mexico
).
Spirobranchus giganteus giganteus
.— ten
Hove, 1970: 16–17
, 20–22, 49, figs. 46–47 (synonym of
S. incrassatus
Krøyer
[in]
Mörch, 1863
).
Material examined.
Sixty-three specimens:
Baja California Sur
(
Mexico
), UMAR-Poly 99,
7 spec.
(23º24– 25’N,
109º25’W
,
Cabo Pulmo Reef
,
Coral Los Frailes
and third bar, on dead coral
Pocillopora
,
4–17 m
,
Sept. 25, 1988
and
Sept. 18, 1989
, coll. PH, JK & JRBZ, as
S. giganteus
);
ECOSUR
s.n.
, UMAR-Poly 100,
12 spec.
(approx.
26º00’51”N
,
111º20’21”W
,
Loreto
pier, in pier pilots, oysters,
March 3, 2004
, coll. MATH & PSS)
.
Sinaloa
(
Mexico
),
ECOSUR
s.n.
, UMAR-Poly 101,
2 spec.
(approx.
23º14’N
,
106º27’W
, Isla
Venados
,
Mazatlan
, basaltic rocks, algae and sand,
2 m
,
Feb. 26, 2004
, coll. MATH & PSS)
.
Colima
(
Mexico
), UANL 350 (approx. 19º03–06’N, 104º18–22'W,
Manzanillo
,
Oct. 7, 1981
, coll.
S. Salcedo Martínez
, as
S. giganteus
)
.
Guerrero
(
Mexico
), SV-pc, 25+ spec. (
16º50’33”N
,
99º54’39”W
,
Punta Manzanillo
,
Acapulco
,
Aug. 4 and 20, 1988
, coll. SISV); SV-pc,
6 spec.
(
16º51’26”N
,
99º52’20”W
,
Condesa
beach,
Acapulco
,
Nov. 27, 1999
, coll. SISV); UMAR-Poly 102,
9 spec.
(
16º50’N
,
99º54’W
,
Cantiles
and
La Quebrada
,
Acapulco
, on rock oysters and
Pinctada
,
8 m
,
May 25 and 26, 2000
, coll.
A. Medina
)
.
Oaxaca
(
Mexico
), UMAR-Poly 103 (
15º51’N
,
97º04’W
,
Puerto Escondido
,
on
Spondylus calcifer
, M10, 6–
10 m
,
July 4, 2004
, coll. SS)
.
Diagnosis.
Tube white, greyish or violet, sometimes covered with bryozoans or coralline algae, with prominent longitudinal ridge. Anteriormost section of tube forms robust spine extending over opening of tube, usually this spine and opening violet, pinkish or bluish in colour; lacking peristomes or alveoli. Opercular peduncle with wide wings. Operculum calcareous, circular or pear-shaped. Opercular surface bears three spines, emerging from dorsalmost part of opercular plate. Two latero-dorsal spines thin, with an additional 6– 10 spinules and one small and thin basal branch; the medio-ventral third spine widely bifurcated (
Figs 12C– D
). Radioles arranged in spire of up to five whorls. Thoracic membrane extends to last thoracic chaetiger, forming short ventral apron. Collar with “
Spirobranchus
” chaetae, coarsely serrated in sub-apical section.
Measurements.
TL=36.5 mm (n=9, r:14–36.5, µ=27.7 ±8.3), THL=
6 mm
(n=10, r:3.5–6, µ=5.1 ±1.1), THW=
6 mm
(n=10, r:2.5–6, µ=4.1 ±1.1), POL=
13 mm
(n=10, r:6–13, µ=9 ±2.2), OL=
6 mm
(n=10, r:2.5–6, µ=4.1 ±1.1), OW=
5 mm
(n=10, r:2.3–5, µ=3.9 ±1), SL=
5 mm
(n=10, r:2–5, µ=3.5 ±1).
Habitat.
Depth:
6–
17 m
. On live and dead coral (
P. verrucosa
), on spiny oyster
Spondylus calcifer
and
Pinctada
, and on pier pilots.
Distribution.
Tropical Eastern Pacific.
Baja California Sur
(
Mexico
) to
Panama
and
Colombia
(Krøyer [in]
Mörch 1863
;
Ehlers 1887
; ten
Hove 1970
;
Bastida-Zavala 1995
).
Taxonomic remarks.
Ten
Hove (1970)
considered the population of
S. incrassatus
from the Eastern Tropical Pacific as a subspecies (
S. giganteus incrassatus
), since most of his specimens had opercula with slight differences to
S. giganteus
from the Caribbean Sea.
Spirobranchus giganteus
was a common name in the Eastern Pacific species checklists. With the material revised here (more than
60 specimens
), from localities from Baja California Sur to
Panama
,
Fiege and ten Hove’s (1999: 363)
opinion that
S. incrassatus
is different from
S. giganteus
, can be confirmed because of the following:
1) All measurements of the specimens of
Spirobranchus giganteus
are greater those of
S. incrassatus
; particularly in the ratio between thorax length and peduncle which separates the two species (
Fig. 12E
).
2) The mid-ventral spine in
S. incrassatus
(present in 90% of the specimens) has a wide bifurcation (1/3 to 1/2 of the total length of the spine) and more additional spinules (6–8) in each lateral spine (
Fig. 12C
); while in
S. giganteus
, whenever a mid-ventral spine is present (in less that 50% of the specimens), it exhibits short bifurcation (1/4 of the total length of the spine) and fewer additional spinules (0–5).