Deep-water Photinae (Gastropoda: Nassariidae) from eastern Africa, with descriptions of five new species
Author
Fraussen, Koen
5F9EFCF2-5BCF-486E-8D3E-088D85C45882
Research Associate Institute of Systematics, Evolution, Biodiversity (ISYEB), Muséum national d’histoire naturelle (MNHN), CNRS, SU, EPHE, UA, CP 51, Rue Cuvier 57, 75005 Paris, France. & Leuvensestraat 25, 3200 Aarschot, Belgium.
koen.fraussen@skynet.be
Author
Galindo, Lee Ann
B84DC387-F1A5-4FE4-80F2-5C93E41CEC15
Research Associate Institute of Systematics, Evolution, Biodiversity (ISYEB), Muséum national d’histoire naturelle (MNHN), CNRS, SU, EPHE, UA, CP 51, Rue Cuvier 57, 75005 Paris, France.
akamaikai@gmail.com
Author
Rosado, José
0415DDDF-2BC1-40CC-9DF6-06146A31C7AB
Avenida Friedrich Engels 373 - 1 °, 1101 Maputo, Mozambique.
joserosadoi@hotmail.com
text
European Journal of Taxonomy
2020
2020-10-16
720
144
169
journal article
9730
10.5852/ejt.2020.720.1123
b2af6f58-5672-4dd6-b1f1-b8ad884ae1b6
4106593
C77C4C91-762D-4A06-82FA-3C58294E1570
Phos ganii
sp. nov.
urn:lsid:zoobank.org:act:
CADD5662-D4B1-4160-B2DE-ED8D470BF685
Figs 2
,
8
Etymology
Phos ganii
sp. nov.
is named to honour the late Gani Satar for his contributions to malacology, as he was one of the very first people who collected Mozambican shells. Gani passed away on
April 19, 1998
in
Mozambique
.
Material examined
Holotype
MOZAMBIQUE
• dd (
27.2 mm
);
Mozambique Channel
,
Maputo
transect, near
Maputo
, MAINBAZA stn CP3143;
23°32′ S
,
35°46′ E
;
264–277 m
;
Apr. 2009
; MAINBAZA exped.;
MNHN
IM-2015-485
(
Figs 2
A–D, 8).
Paratypes
MADAGASCAR
• 3 dd;
Mozambique
Channel, off Majenga;
on
Xenophora pallidula
(Reeve, 1842)
, trawled in deep water; 2000; local fishermen leg.;
paratypes
11–13; KF 2556 (
Fig. 2
K
)
•
2 dd; same locality as for preceding;
on
Xenophora pallidula
; 2000; local fishermen leg.;
paratypes
14–15; KF 5236
•
1 dd
; from old collection;
paratype
16;
KF 7702
.
MOZAMBIQUE
• 1 dd; same collection data as for
holotype
;
paratype
1;
MNHN
IM-2000-35085
(
Fig. 2
E–G)
•
2 dd;
S
Mozambique
, off
Maputo
;
on
Xenophora pallidula
; depth
150–350 m
; local fishermen leg.; trawl;
paratypes
2–3; KF 5419
•
1 dd;
S
Mozambique
, off
Massinga
;
23°32′ S
,
35°47′ E
;
270–320 m
;
Nov. 2005
;
J. Rosado
leg.; trawl;
paratype
4; JR
.
TANZANIA
•
3 lv
;
S Tanzania
, off
North Rovuma River
;
7°24′ S
,
39°51′ E
; depth 330–360;
Nov. 2005
; Portuguese fishery vessel; trawl;
paratypes
5–7; JR (
paratype
5,
Fig. 2H
;
paratype
6,
Fig. 2
I–J)
•
3 dd; same collection data as for preceding;
on
Xenophora pallidula
;
paratypes
8–10; JR
.
Other material
MOZAMBIQUE
• 1 fragment; off
Maputo
;
on
Xenophora pallidula
; depth
150–350 m
; local fishermen leg.; lot also contains
paratypes
2–3; trawl; KF 5419
.
Fig. 2.
Phos ganii
sp. nov.
A–C
. Holotype, Mozambique Channel, Maputo transect, MAINBAZA stn CP3143, 23°32′ S, 35°46′ E, depth 264–277 m, 27.2 mm long (MNHN IM-2015-485).
D
. Apex of holotype.
E–F
. Paratype 1, same collection data as for holotype, 29.3 mm long (MNHN IM-2000- 35085).
G
. Protoconch of paratype 1.
H
. Paratype 5, S Tanzania, off North Rovuma River, 7°24′ S, 39°51′ E, trawled by Portuguese fishery vessel, depth 330–360 m, 22.8 mm long (JR).
I–J
. Paratype 6, same collection data as for preceding, 23.4 mm long (JR).
K
. Paratypes 11–13, Madagascar, Mozambique Channel, off Majenga, trawled in deep water, on
Xenophora pallidula
(Reeve, 1842) (KF 2556)
. Scale bars: A–C, E–F, H–K = 5.0 mm; D, G = 1.0 mm.
Description
(
holotype
)
GENERAL. Shell rather small for the genus,
27.2 mm
in length. Shape broadly fusiform with moderately high spire, base stretched, giving a biconical appearance. Suture rather deep, accentuated by narrow, flattened shoulder of subsequent whorl. Sculpture cancellate, forming knobs where fine spiral sculpture crosses broader axial ribs. Colour white or yellowish to pale brown, spiral cords often brown (
Fig. 2
A–C).
PROTOCONCH (
Fig. 2D
). Multispiral, tip chipped, with 3 remaining whorls, total of about 3¾ whorls by estimation, 1.0 mm high, diameter 1.0 mm; white with spiral cords of same colour, with 1 spiral cord initially concealed under suture with subsequent whorl, appearing on last half; second whorl with fine but sharp spiral cord, suprasuturally situated; this spiral cord more adapically situated along third whorl, with a second spiral cord appearing from below suture with subsequent whorl; last whorl with 3 such spiral cords, its last ¼ part with a few fine, opisthocline axial riblets adapically of those spiral cords. Transition to teleoconch marked by fine line and start of teleoconch sculpture.
TELEOCONCH. Consisting of 6½ weakly convex whorls. First teleoconch whorl starting with 6 fine spiral cords of which subsutural one weaker, their strength gradually increasing, with 1 fine secondary spiral thread appearing in interspaces. Second whorl with 6 such spiral cords, interspaces with 3 fine secondary spiral cords. Third whorl with 6 strong primary spiral cords, interspaces starting with 3 (in abapical interspaces) to 5 (in adapical interspaces) secondary spiral cords. Primary spiral cords gradually more pronounced along spire, but their number remaining constant. Penultimate whorl with 6 moderately large primary spiral cords; interspaces broad, with 3 (in abapical interspaces) to 5 (in adapical interspaces) secondary spiral cords (these cords quite difficult to count with precision). Body whorl with 15 spiral cords, 6 abapical ones moderately large with broad interspaces, on base only slightly weaker, with narrower interspaces with 1–3 fine secondary spiral cords.
APERTURE. Large, semi-oval but rather narrow for genus, adapically weakly pinched. Columella with 2 strong columellar folds. Parietal part straight. Adapical border of aperture broad, formed by shoulder of body whorl. Outer lip thick, with 13 or 14 thin but moderately sharp internal lirae, extending far into aperture; edge sharp. Aperture with siphonal canal more than
2
/
5
of total shell length. Siphonal canal rather long for genus, broad, open, covered by fine spiral cords on outside.
Distribution and habitat
Known from deep water in
Mozambique
Channel (
Mozambique
and
Madagascar
) in the south to southern
Tanzania
in the north (
Fig. 8
).
Live-collected specimens were found at between 330 and
360 m
in
Tanzania
and empty shells between about 264 and
800 m
.
The species is found attached to
Xenophora pallidula
quite frequently and according to our observations more often than for other deep-water
Nassariidae
and
Buccinidae
. Besides being a useful secondary collecting method (Terryn 2008: 1–4) this also may throw some light on habitat characteristics.
Remarks
Phos ganii
sp. nov.
is characterized by its somewhat biconical shape and deep suture, the usually constant number of 6 primary spiral cords, the moderately large knobs, formed where spiral and axial sculptures cross, and by the rather narrow aperture with moderately long siphonal canal. The shape is reminiscent of that in the Carribean genus
Antillophos
(
Galindo
et al
. 2016
)
in outline and sculpture.
The colour is usually white or yellowish to pale brown (see
holotype
), while fresh specimens (
paratypes
5, 7, 11–13, 16) may be slightly darker with 3 broad but only slightly darker spiral bands.
The number of fine secondary spiral cords on the base is usually 1–3, in some
paratypes
they occasionally grow up to 4.
Variability in sculpture is low while size may vary considerably;
paratypes
5–7 (
22.8–25.1 mm
) have 6 to 6½ whorls,
paratypes
11–13 (
21.3–23.2 mm
) are only slightly smaller but have about 5½ whorls.
Phos durianoides
(
Fraussen & Poppe, 2005
)
looks similar but differs from
P. ganii
sp. nov.
by its rather semi-oval shape, the strong knobs where spiral and axial sculptures cross and the broad secondary spiral cords with a fine groove as interspace.
Phos gemmulifer
Kilburn, 2000
(
Fig. 1
D–E) differs from
P. ganii
sp. nov.
by its broader shape, thicker shell, larger knobs and larger size.
Phos retecosus
Hinds, 1844
(
type
locality: “
Ceylon
”) differs from
P. ganii
sp. nov.
by its broader shape, the smoother subsutural area, the presence of brown lines on top of the spiral cords and some brownish bands on the body whorl and on the labral varix. The size is slightly larger.