Revision of Autolytinae (Syllidae: Polychaeta).
Author
Nygren, Arne
text
Zootaxa
2004
680
1
314
journal article
42299
10.5281/zenodo.157809
43595c87-02cf-47ba-ba28-0cb07de78adc
1-877354-52-X
157809
471A4E52-4C92-44F8-AB38-CD03071C0067
Paraproceraea
gen. n.
Linnean name definition
.
Type
species
Autolytus(Autolytus) tamanus
Imajima, 1966
.
PhyloCode definition
. No name definition provided.
Apomorphies
. Supported by 2 morphological characters (
Fig. 4
): 1)
nuchal epaulettes extend to chaetiger 3
(character 8), character state change is a reversal, and a parallelism; 2)
number of teeth> 65
(character 40), character state change is a parallelism.
Etymology
. Para is greek and means close to. Named for its similarity to
Proceraea
.
Paraproceraea tamana
(
Imajima, 1966
)
comb. n.
(Fig. 47A–F)
Autolytus (Autolytus) tamanus
Imajima, 1966
: 46
–47, fig. 11E–K. NOT
Autolytus tamanus
San Martín 1994
272–273, fig. 2A–D.
Material examined
.
Japan
:
holotype
NSMTPol
H
1, Tamano, Torishima, 1964,
2 m.
Diagnosis
.
Procerini
with nuchal epaulettes reaching middle of chaetiger 3, a thick
type
of bayonet chaetae, distally denticulated, and 90 small subequal teeth in trepan.
Description
. Length
7.5 mm
for 42 chaetigers, incomplete, width excluding parapodial lobes
0.5 mm
at level of proventricle. Preserved material yellowish without colour markings, eyes brownish red. Live specimen orange with brown spot at the base of each dorsal cirri (
Imajima 1966
).
Body, excluding parapodial lobes, cylindrical, venter flattened; body width fairly constant. Ciliation not possible to assess, anterior segments appear triannulated (Fig. 47A).
Prostomium rounded rectangular, wider than long. Four eyes, with lenses, in trapezoid arrangement, anterior pair larger. Eyes large, in dorsal view almost confluent (Fig. 47A); eye spots absent. Palps in dorsal view projecting 1/4 of prostomial length (Fig. 47A), fused. Extension of nuchal epaulettes to half of chaetiger 3 (Fig. 47A).
Antennae and first dorsal cirri lost. Dorsal tentacular cirri reaching chaetiger 7. Ventral tentacular cirri 1/3 as long as dorsal pair, second dorsal cirri as long as ventral tentacular cirri. From chaetiger 1–27 cirri with usual alternation in direction, followed by 3 DDUUgroups. Dorsal cirri from chaetiger 3 of equal length (Fig. 47B), 1/3 of body width excluding parapodial lobes. Cirrophores on tentacular segment and first dorsal cirri present; cirrophores otherwise absent (Fig. 47B). All appendages cylindrical, including lost anterior appendages (
Imajima 1966
).
Parapodial lobes rounded, small (Fig. 47B). Aciculae numbering
2–3 in
all present chaetigers. Chaetal fascicle with 10–15 compounds. Compound chaetae with small distal tooth in anterior 5–10 chaetigers (Fig. 47C), more posterior with larger distal tooth, still smaller than subdistal tooth (Fig. 47D); serration present. Single thick bayonet chaetae, distally denticulated (Fig. 47E), beginning from chaetiger 20.
Pharynx with sinuation anterior and lateral to anterior half of proventricle (Fig. 47F).
Trepan dissected, lost. Proventricle equal in length to 2 segments in chaetiger 5–6 with c. 25 rows of square shaped muscle cells. Posterior part lost.
Reproduction
. Unknown.
Additional information
.
Imajima (1966)
describes the trepan as having 90 subequal teeth arranged in one ring.
Habitat
. Intertidal.
Distribution
. North West Pacific. Southern
Japan
. Only known from
type
locality.
Remarks
.
Paraproceraea tamana
is only known from one anterior end. The record of
P. tamana
from
Cuba
is not considered reliable, since the specimen has a thin bayonet chaetae, subdistally denticulated while the bayonet chaetae of
P. tamana
is thick, distally denticulated. The details of compound chaetae and proventricle do not match either.
P. tamana
is unique in having a combination of thick bayonet chaetae with 90 small subequal teeth. Unfortunately the trepan has been lost, and it is not possible to confirm Imajima's observations. Other
Procerini
with many teeth (>40) in their trepan includes
Imajimaea zonata
,
I. japonensis
(
Imajima & Hartman, 1964
), and
I. tsugara
(
Imajima, 1966
)
; all these taxa have thin bayonet chaetae, subdistally denticulated.