Revision of Leocrates Kinberg, 1866 and Leocratides Ehlers, 1908 (Annelida, Errantia, Hesionidae)
Author
Salazar-Vallejo, Sergio I.
text
Zootaxa
2020
2020-02-18
4739
1
1
114
journal article
23993
10.11646/zootaxa.4739.1.1
d3e60fb6-636b-4e03-b55a-0e910f9a468e
1175-5326
3672547
544B9C82-BF33-4EA1-9411-E1A307137466
Paralamprophaea bemisae
n. sp.
Fig. 52
urn:lsid:zoobank.org:act:
11F8BEC6-801D-4188-B819-6C263690CAE2
Leocrates diplognathus
:
Fauvel, 1932: 62
;
1953b: 107
,
Fig. 50
a–b (anterior end copied from
Monro, 1926
) (
non
Monro, 1926
).
Type material
.
Central Indian Ocean,
Maldives
.
Holotype
(
UF 4141
),
Capital Reef, S
coast of
Nilandoo Island
(
03°02’55.68” N
,
72°53’21.12” E
),
20 m
,
16 May 2014
,
M. Oliveiro
&
M. Taviani
, coll.
Description
.
Holotype
(UF 4141) complete, slightly bent dorsally, anterior end depressed after pressure upon fixation, mature. Body oboconic, tapered, wider anteriorly,
20.5 mm
long,
2.5 mm
wide (without parapodia); left parapodium of chaetiger 8 removed for observing parapodial features. Body brownish, wide transverse segmental bands separated by paler intersegmental thinner bands, with similar pigmentation intensity throughout dorsum (
Fig. 52A
), but corresponding bands of tentacular belt and chaetigers 1 and 2 fused, bands of chaetiger 16 and preanal segment with intersegmental paler band incomplete; bands better defined along anterior margin, posterior margin middorsaly indented. Dorsal cirri barely banded brown and pale, tapered.
Prostomium as long as wide, wider medially by compression, slightly damaged, with a complex pigmentation pattern extending into palps and nuchal organs lateral branches (
Fig. 52B, C
). Darker areas connected into an irregularly banded shape, extended anteriorly as an inverted U, leaving a central prostomial area paler, and a posterior W with the lower areas solid, continued into nuchal organs lobes. Lateral antennae with ceratophores distinct, antennae shorter than prostomium, slightly shorter than palps; palpophores 2–3 times longer than palpostyles; median antenna distorted by compression, reaching anterior prostomial margin, inserted between anterior eyes.
Eyes dark-brown, anterior eyes reniform, twice larger than posterior round ones, and more distant to each other than posterior eyes (
Fig. 52C
).
FIGURE 52
.
Paralamprophaea bemisae
n. sp.
, holotype (UF 4141). A. Dorsal view (darkened middle region slightly more shaded than the rest). B. Anterior region, dorsal view. C. Anterior end, dorsal view. D. Chaetiger 8, left parapodium, anterior view (inset: notacicular lobe). E. Neurochaetae (insets: middle and lower neurochaetal blades). Scale bars: A: 1.7 mm, B: 0.9 mm, C, D: 0.3 mm, E: 0.1 mm.
Nuchal organs lobes L-shaped, lateral lobes not surpassing level of lateral prostomial margins; lateral ciliated bands not visible, obliterated by compressed lateral prostomial margins. Tentacular cirri banded with brownish bands, each band darked medially, longest ones reaching chaetiger 5. Lateral cushions barely projected laterally, entire, longitudinal striae visible.
Pharynx not exposed, observed by dissection. Anterior margin smooth. Jaws hyaline, golden; upper jaw double, lower one single. Lateral vesicles not seen. Basal pharynx ring with 1–3 series of tapered papillae, decreasing in number dorsally and ventrally, middorsal and midventral regions smooth.
Dorsal cirri smaller than body width. Chaetigers 1–4 without notochaetae; notochaetae present along chaetigers 5–16, first notochaetal lobe well-developed, slightly smaller than those present in chaetigers 6–8 (
Fig. 52D
, inset), notochaetae scarce, about 20 per bundle, delicate, arranged in bundles, notochaetae subdistally denticulate, denticles small. Notacicular lobes short, round, slightly longer than wide; neuracicular lobes blunt, wider than long. Neurochaetae about 20 per bundle; neurochaetal blades bidentate, 2–5 times longer than wide, guards approaching subdistal tooth (
Fig. 52E
, insets).
Posterior region tapered. Prepygidial segment with cirri banded, dorsal ones 4–5 times longer than ventral ones. Pygidium with anus terminal; anal cirri banded reaching chaetiger 15.
Oocytes not seen; testis visible through chaetiger 8 are testis.
Etymology
. The specific epithet is derived after Miss Amanda Bemis, Collection Manager of the University of
Florida
Museum of Natural History, Gainesville, in recognition of her help and support for my research activities. The species-group name is a noun in the genitive case (
ICZN 1999
,
Art
. 31.1.2).
Remarks
. The pigmentation pattern of
Paralamprophaea bemisae
n. sp.
differs from the two other similar species,
P. diplognatha
(
Monro, 1926
)
n. comb.
from the South
China
Sea, and
P. leslieae
n. sp.
from
Kiribati
, because in
P. bemisae
the dorsal pigmentation is homogeneous throughout the body, not progressively paler posteriorly as shown in the two other species. The species might have been already recorded from the Eastern Indian Ocean by
Fauvel (1932: 62
,
1953b: 107
), as
Leocrates diplognathus
,
from the Mergui Archipelago,
Birmania
. He indicated the dorsal pigmentation as “dark chestnut-brown traversed by intersegmental bands of white”. However, in the original description,
Monro (1926: 313)
indicated that the “colouring is more intense in the anterior segments, and in two examples it disappears altogether behind the first half-dozen segments.” Because
Fauvel (1932)
did not indicate any variation in pigmentation intensity, the affinities of these two Indian Ocean records would be clarified after a comparison with his specimens, but currently they are not available.
Distribution
. Only known from the
Maldives
, in the Central Indian Ocean, in
20 m
depth.