Lissodendoryx (Ectyodoryx) Lundbeck, 1909 (Coelosphaeridae, Poecilosclerida, Demospongiae) from Southern Chile: new species and a discussion of morphologic characters in the subgenus
Author
Fernandez, Julio C. C.
Author
Cárdenas, César A.
Author
Bravo, Alejandro
Author
Lôbo-Hajdu, Gisele
Author
Willenz, Philippe
Author
Hajdu, Eduardo
text
Zootaxa
2016
4092
1
journal volume
10.11646/zootaxa.4092.1.4
f448a9b2-e7ab-4dbf-87a1-64d0338b8b95
1175-5326
266115
51F44763-E817-4E58-A4AC-525E63B6D27B
Lissodendoryx
(
Ectyodoryx
)
diegoramirezensis
sp. nov.
(
Tab. 2
;
Figs 10–13
)
Holotype
.
IZUA–POR 169,
Isla
Diego Ramírez, southern
Chile
(56ºS, off Cape Horn), ca.
2000 m
depth,
September 2002
, bycatch from longline fisheries, Leg. A. Bravo. Fragment from
holotype
deposited under MNRJ 10884.
Comparative material.
Lissodendoryx
(
Ectyodoryx
)
anacantha
(Hentschel, 1914)
(ZMH S 2327, fragment from the
holotype
).
Diagnosis.
Seemingly erect
Lissodendoryx
(
Ectyodoryx
)
with irregular surface, terminally microspined tylotes (223–252/7.2–9.6), acanthostyles (I. 435–602/24–31, II. 320–415/19–21, III. 220–242/14–17), arcuate isochelae with lateral alae bent towards the shaft (22–24), and sigmas (
I.45
–60, II. 18.6–25).
Description.
The
holotype
is incomplete and therefore imprecise to describe its gross morphology. It is seemingly erect, possibly stalked (
Fig. 10A
), ca.
2 cm
high and
0.4 cm
thick. Surface rather hispid, irregular, bearing short projections (
Fig. 10B
) and roundish openings (ca.
0.1 cm
across), which are of doubtful oscular in function. A gross reticulation is apparent in the entire sponge under transmitted light in a stereo microscope (
Fig. 10C
). Colour in life not reported, dried
holotype
beige. Consistency relatively compressible and delicate, texture slightly rough.
Skeleton.
Plumoreticulate with a slight degree of axial compression (
Figs 11
A–B). Larger acanthostyles core main paucispicular tracts (approx. five spicules across) that are entirely echinated by another two distinct
types
of acanthostyles (
Fig. 11
C). Some of the larger acanthostyles fan out from the main tracts, interconnecting them. Aniso-subtylotes are scattered at the surface, disposed at various angles to it (
Fig. 11
D). Isochelae and sigmas are scattered in the ectosome and choanosome. There is no spongin enveloping the fibres and subectosomal lacunae are absent. Choanosomal cavities (ca. 50 µm in diameter) are uncommon, scattered and roundish.
Spicules.
Megascleres (
Tabs 2
–4): Aniso-subtylotes to aniso-strongyles (
Figs 12
A–B), straight, microspined
ends
, 223–
233.5
(10.2) –252/7.2–
8.4
(1.3) –9.6. Acanthostyles I (
Figs 12
C–D), straight to slightly curved, stout and somewhat fusiform; roundish base, frequently narrower than the central portion of the shaft; gradually thinning point; surface with few straight spines (up to 2.5 µm), mainly over the basal third of the spicule, 435–
536
(52.8) – 602/24–
26.6
(2.4) –31. Acanthostyles II (
Figs 12
E–F), same overall morphology as the preceding category, but smaller, and bearing more spines, although the apical portion is also totally smooth, 320–
391
(29.2) –415/19–
20
(1) –21. Acanthostyles III (
Fig. 12
H) straight to slightly curved; narrow roundish base; gradually thinning point; shaft completely covered with spines (moderately to abundantly), spines frequently straight and usually larger than those of the preceding categories, 220–
232.5
(10) –242/14–
15
(1.1) –17. Microscleres (
Tabs 2
–4): Arcuate isochelae (
Fig.
12
I), shaft gently curved, lateral alae elongated and curved towards the shaft as a claw, frontal alae simple, 22–
23.5
(1) –24. Sigmas I (
Fig. 12
J), contorted, smooth, with sharp
ends
, 45–
55.5
(4.9) –60. Sigmas II (
Fig. 12
K) same morphology as the preceding one, but smaller, 16.8–
20.8
(2.9) –25.
Ecology.
Deep-water habitat (
2000 m
depth).
Distribution.
Currently only known from the
type
locality.
Etymology.
The species is named after its
type
locality.
Remarks.
Lissodendoryx
(
Ectyodoryx
)
diegoramirezensis
sp. nov.
is distinguished from
Lissodendoryx
(
E.
)
spp. occurring in the SE Pacific, additional allied biogeographic provinces, as well as
L.
(
E
.)
ballena
sp. nov.
,
L.
(
E
.)
corrugata
sp. nov.
, and
L.
(
E
.)
coloanensis
sp. nov.
, mainly by its possession of three categories of acanthostyles, separable by their dimensions, morphology and placement in the skeletal architecture (
Tab. 2
;
Figs 12
C–H).
FIGURE 10.
A–C,
Lissodendoryx
(
Ectyodoryx
)
diegoramirezensis
sp. nov.
, habit. A–C, holotype (IZUA–POR 169). A, whole specimen (dry); B, markedly hispid surface in detail; C, surface under transmitted light showing reticulated pattern. Scales: A = 0.5 cm; B–C = 0.1 cm.
FIGURE 11.
Lissodendoryx
(
Ectyodoryx
)
diegoramirezensis
sp. nov.
, skeleton. A–D, holotype (IZUA–POR 169): A, overview of skeletal architecture; B, choanosomal reticulation in detail; C, section of a main tract echinated by smaller acanthostyles, i = larger acanthostyle, ii = intermediate acanthostyle, iii = smaller acanthostyle; D, detail of surface with tylotes scattered in disorder. Scales: A = 500 µm; B–D = 200 µm.
FIGURE 12.
Lissodendoryx
(
Ectyodoryx
)
diegoramirezensis
sp. nov.
, electron micrographs. A–K, holotype (IZUA–POR 169): A, aniso-subtylotes; B, extremities of the aniso-subtylotes; C, acanthostyles I; D, bases of acanthostyles I; E, acanthostyles II; F, bases of acanthostyles II; G, acanthostyles III; H, bases of acanthostyles III, and sigma II; I, arcuate isochelae; J, sigmas I; K, sigmas II. Scales: A, C, E, G =100 µm; B = 5 µm; D, F, H–I, K = 10 µm; J = 20 µm.
Lissodendoryx
(
Ectyodoryx
)
diegoramirezensis
sp. nov.
has arcuate isochelae of uncommon morphology, with lateral alae of both extremities curved towards the shaft (
Fig.
12
I). Precisely this isochelae morphotype can be found in
L.
(
E.
)
anacantha
(Hentschel, 1914: p.107, Taf. VII,
Fig. 12
), a species amply distributed around
Antarctic
and the Subantarctic Region, and in another
Antarctic
species,
L.
(
Lissodendoryx
)
styloderma
Hentschel, 1914
(Hentschel, 1914: p.101, Taf. VII,
Fig. 7
). This latter species can be readily distinguished from the new species by its lack of sigmas, possession of styles in the ectosome, and acanthostyles of a single category only. However, the similarity of the isochelae of the new species and those seen in
L.
(
E.
)
anacantha
might indicate a closer affinity between both species, as they further share similar habit and additional spicule characteristics. Nevertheless, both species are considered distinct on the basis of the presence of a third category of acanthostyles in the new species, while its acanthostyles, as a rule, are also more densely spined or with spines more widespread over the shaft. Furthermore,
L.
(
E.
)
anacantha
has ectosomal megascleres that can be perfect styles (
Fig. 13
C–D), and the smaller category of acanthostyles may bear secondary microspines over the main spines seen at the base of the spicule (
Fig. 13
E–F). These characteristics of the acanthostyles have not been spotted in the
holotype
of
L.
(
E.
)
diegoramirezensis
sp. nov.
(
Fig. 11
C–H). The re-examination of the
type
material of
L.
(
E.
)
anacantha
(
Fig. 13
) confirmed the spicule set originally reported by Hentschel (1914), and subsequently recognized by Koltun (1964). Nevertheless, new measurements obtained from the
holotype
(
Tab. 2
) revealed that acanthostyles can be much thicker than reported originally (Hentschel, 1914), matching more closely the measurements reported by Koltun (1964).
Given the data at hand,
L.
(
E.
)
diegoramirezensis
sp. nov.
is considered well distinguished from allied forms, but it is suggested that study of additional samples of
L.
(
E.
)
anacantha
, such as those registered (but not described) by Burton (1932) from
South Georgia
, is important to verify if these two taxa are distinct, as hypothesised here.