Evolution of Janthina and Recluzia (Mollusca: Gastropoda: Epitoniidae)
Author
Beu, Alan G.
text
Records of the Australian Museum
2017
Rec. Aust. Mus.
2017-08-23
69
3
119
222
http://dx.doi.org/10.3853/j.2201-4349.69.2017.1666
journal article
228171
10.3853/j.2201-4349.69.2017.1666
d63960a1-e0c5-4b97-8e7d-f8be80d376d6
2201-4349
4677010
Janthina exigua
Lamarck, 1816
Figs 2M, O
,
34A–C, E–F
Janthina exigua
Lamarck, 1816
, “Liste des objets”: 12, pl. 456, figs 2a–b;
Eschscholtz, 1825
: column 737;
Gray, 1827: 495
;
Deshayes, 1843: 5
;
Gray, 1843: 241
;
Benson, 1860: 40
;
Küster, 1868: 7
, pl. 2, figs 6–7;
Monterosato, 1878: 95
;
Hutton, 1882: 128
, pl. 14, fig. G (radula);
Hutton, 1904: 80
;
Moss 1908: 28
, pl. 7, fig. 1;
Suter, 1913: 299
, pl. 44, fig. 12;
Oliver, 1915: 525
;
Bucknill, 1924: 50
, pl. 19, fig. 4;
Finlay, 1928: 246
;
Powell, 1937: 74
, pl. 10, fig. 30;
Mermod, 1953: 201
, figs 200.1–2; PasteurHumbert, 1962: 52, fig. 72;
Bennett, 1966: 41
, pl. 9, fig. 2; Morton & Miller, 1968: 472, fig. 175.5;
Cernohorsky, 1972: 198
, pl. 56, fig. 10;
Powell, 1976: 107
, pl. 17, fig. 30:
Kay, 1979: 158
, fig. 55C;
Powell, 1979: 254
, pl. 48, fig. 21; Fretter & Graham, 1982: 394, fig. 281; Kilburn & Rippey, 1982: 79, pl. 11, fig. 19; Wells & Bryce, 1986: 60, fig. 153;
Wilson, 1993: 281
, pl. 44, figs 37a–b;
Giannuzzi-Savelli
et al
., 1999: 52
, 53, figs 94a–d, 95a–b;
Smith, 1998: 813
, figs 15.151C, G;
Morley, 2004: 102
;
Robertson, 2007a: 5
, fig. 1; Beu & Marshall, 2008: 285;
Poppe, 2008: 722
, pl. 306, fig. 1;
Spencer
et al.
, 2009: 206
; Raven & Bracegirdle, 2010: 27, text-fig.;
Willan
et al
., 2010: 385
, text-fig.;
Grove, 2011: 40
, pl. 18, fig. 9;
Severns, 2011: 198
, pl. 82, fig. 1;
Hernández
et al
., 2011: 97
, figs 30A–D.
Ianthina exigua
.–
G. B. Sowerby I, 1822: 2nd
Ianthina
page, pl. 191, figs 2–3;
Bronn, 1826: 328
; d’Orbigny, 1841: 414; Reeve, 1842: 145, pl. 205, figs 2–3 (repeat of Sowerby’s 1822 figs); d’Orbigny, 1846: 84; Forbes & Hanley, 1853, vol. 2: 555, pl. 69, figs 8–9; H.Adams & A.Adams, 1854: 87;
Reeve, 1858
: pl. 5, figs 21a–b;
Chenu, 1859: 118
, fig. 519;
Benson, 1860: 408
;
Angas, 1865: 190
;
Angas, 1867: 231
;
Hutton, 1873a: 6
;
Martens, 1873: 39
;
Tenison Woods, 1878: 43
;
Hutton, 1880: 71
; G. B. Sowerby II, 1882: 51, pl. 444, figs 23–24;
Watson, 1886: 134
;
Tryon, 1887: 37
, pl. 10, figs 17–22;
Whitelegge, 1889: 262
;
Locard, 1898: 4
; Pritchard & Gatliff, 1900: 140; Tate & May, 1901: 407;
Martens, 1904: 143
;
Verco, 1908: 9
;
Iredale, 1910: 71
; Macpherson & Chapple, 1951: 124;
Laursen, 1953: 22
, figs 22–24;
Macpherson, 1958: 33
, pl. 29, fig. 4; Macpherson & Gabriel, 1962: 119, fig. 146.
Janthina incisa
Philippi, 1849: 149
; H.Adams & A. Adams, 1854: 87;
Tryon, 1887: 38
.
Ianthina nana
J. E.
Gray, 1850: 9
, 101 (caption to M. E. Gray, 1842: pl. 48, figs 3–4).
Ianthina incisa
Philippi.
–
H. Adams & A. Adams, 1854: 87.
Ianthina bifida
“Nuttall
in Jay”
Reeve, 1858
: pl. 5, figs 25a–b.
Janthina capreolata
Montrouzier, 1860: 114
, pl. 11, fig. 4;
Hedley, 1918
: M61;
May, 1921: 63
;
May, 1923
: pl. 19, fig. 4;
Fischer-Piette, 1950: 18
;
Allan, 1950: 95
, text-fig. 22.4.
Janthina (Janthina) nana
Gray.
–
Mörch, 1860: 281
.
Janthina (Iodina) exigua
Lamarck.
–
Mörch, 1860: 282
;
Powell, 1946: 77
, pl. 10, fig. 30;
Powell, 1957: 98
, pl. 10, fig. 30;
Powell, 1962: 91
, pl. 10, fig. 30.
Janthina (Iodina) capreolata
Montrouzier.
–
Mörch, 1860: 283
.
Janthina (Iodina) bifida
Nuttall.
–
Mörch, 1860: 283
.
Ianthina vinsoni
Deshayes, 1863: 94
, pl. 11, figs 9–11.
Jodina exigua
(Lamarck)
.
–
Monterosato, 1884: 106
.
Janthina courcellei
Mabille & Rochebrune
in Rochebrune &
Mabille, 1889: 45
, pl. 6, figs 3a–b [
courcelli
in text,
courcellei
in caption; the latter adopted by Rosenberg (Malacolog 4.1.1)];
Forcelli, 2000: 82
, original illus. copied;
Petit, 2010: 48
.
Janthina (Jodina) exigua
Lamarck.
–
Thiele, 1929: 225
, fig. 228;
Abbott, 1974: 113
, col. pl. 3, fig. 1181;
Rios, 1994: 102
, pl. 33, fig. 416.
Ianthina capreolata
Montrouzier.
–
Cotton, 1932: 537; Cotton & Godfrey, 1932: 36; Cotton & Godfrey, 1938: 16;
Kershaw, 1955: 312
;
Cotton, 1959: 376
.
Iodina capreolata
(Montrouzier)
.
–
Iredale & McMichael, 1962: 49.
Janthina (Violetta) exigua
Lamarck.
–
Higo
et al.
, 1999: 173
.
Type material
.
Janthina exigua
,
3
syntypes
MHNG
1094/80
examined, now catalogued as
MHNG-INVE
51377
, without locality; all are conspecific and agree with
Laursen’s (1953)
and all later interpretations of
J. exigua
.
However, as with
J. communis
, Rosalie
de Lamarck’s annotation on Lamarck’s copy of
Animaux sans vertèbres
states that there is only one specimen in Lamarck’s collection, so at least two and conceivably all three of these specimens are not original
syntypes
, although it is not possible to determine which is (Y. Finet,
MHNG
pers. comm.
27 Sep 2012
). Two of the
syntypes
were illustrated by
Mermod (1953: 201
, figs 200.1–2), who described their angulated axial ridges commarginal with the mid-whorl sinus, and commented on the difficulty of matching any of them with the poor drawings in
Lamarck (1816
: pl. 456, figs 2a–b). The writer is not aware of the location of any type material of
Janthina incisa
, from
Senegal
; possibly in Philippi’s collection in Museo Nacional de Historia Natural, Santiago, not available for consultation, so a new type is not designated here.
The term “aucta” in G. B. Sowerby I’s (1822: second
Ianthina
p., pl. 191, fig. 3) caption to his second illustrated specimen of
Janthina exigua
does not constitute the proposal of a species-group name, but indicates that the illustration is enlarged. In an identical case,
Petit (2009: 192
, taxa note 27) stated that “The position taken here is that “
aucta
” is a descriptive term (= enlarged) and not an available name”. The drawings in
Reeve (1841
–1842, vol. 2: pl. 205) are republications of the illustrations in G. B. Sowerby I (1822: pl. 191), and the term “aucta” appears in
Reeve (1841
–1842: pl. 205) also, at the bottom edge of the plate.
Janthina nana
J. E.
Gray (1850: 9
, 101; caption to M. E. Gray 1842: pl. 48, figs 3–4) refers to an illustration by “Quoy, Voy. Astrol. t. 29, f. 5, 6”, which shows a crudely drawn specimen of
J. exigua
from the Atlantic Ocean. Quoy & Gaimard (1833: caption to pl. 29) identified this specimen with the vernacular name “Janthine naine”, as pointed out by
Mörch (1860: 281
; as “nain”, sic), so Gray merely Latinized Quoy & Gaimard’s species name. Lamarck (1922: 206) earlier provided
J. exigua
with the vernacular name “Janthine naine”, so Quoy & Gaimard were repeating Lamarck’s vernacular name. The specimen of
J. exigua
illustrated by Quoy & Gaimard (1833, pl. 29, figs 5–6) is the
holotype
of
J. nana
. However, this specimen is not recognisable in
MNHN
(P. Bouchet,
MNHN
, pers. comm.
5 Apr 2016
), so the largest
syntype
of
J. exigua
in MHNG-INVE51377 is here designated the
neotype
of
Janthina nana
Gray, 1850
.
Petit (2012: 76)
apparently was not aware of the publication of the name
Janthina nana
by
Gray (1850: 101)
and attributed the name to
Couffon & Surrault (1909: 57)
, where it is a
nomen nudum
.
Janthina capreolata
, two lots of two specimens each in MNHN formerly were considered
syntypes
(
Fischer-Piette 1950: 18
), but as
Montrouzier (1860: 114)
stated that the types were in “ma collection Musée de Bordeaux,
4 ex.
”, the MNHN specimens are not
syntypes
; 3 remaining
syntypes
MHNB2004.TY.160.0; photographs of MHNB
syntypes
sent
21 Sep 2012
(pers. comm. L. Charles, MHNB, and V. Héros, MNHN); from Art Island,
New Caledonia
.
Janthina vinsoni
, no type material in either MNHN or Université Lyon-1, where most of Deshayes’s collection is stored (V. Héros, MNHN, pers. comm.
21 Sep 2012
; E. Robert, Université Lyon-1, pers. comm.
02 Oct 2012
), location unknown; from
Réunion
.
Janthina courcellei
, empty box in typothèque, MNHN, labeled “type perdu”, apparently long lost; from Orange Bay, Tierra del Fuego.
The largest
syntype
of
Janthina exigua
,
MHNG-INVE
51377
, designated above as the neotype of
J. nana
, is here also designated the neotype of both
Janthina vinsoni
Deshayes, 1863
and
Janthina courcellei
Mabille & Rochbrune, 1889
, in order to identify these names permanently with the present species.
Other material examined
. Present-day samples from Australia and New Zealand:
Australia
:
Western Australia
:
Cable Beach, Broome (
NMV
); Duke of Orleans Bay (
AMS
); Bunbury (
AMS
); Leighton (
WAM
); Point Peron,Fremantle (
WAM
.699/70-38,
WAM
.366/40,
WAM
.589/91-38); City Beach, Perth (
AMS
); Esperance (
SAM
,
NMV
); King George Sound (
SAM
); Albany (
SAM
); Rottnest I. (
SAM
); 300 fms,
120 mi
W of Eucla (
SAM
); Ellensbrook Beach (
SAM
).
South Australia
:
Coorong (
SAM
); Grange (
SAM
); Edithburgh (
SAM
); 165, 240 &
550 m
, off Cape Jaffa (
SAM
);
190 m
,
56 km
SW of Neptune I. (
SAM
);
Victoria
:
Portland (
NMV
); Mordialloc (
NMV
); Mallacoota (
NMV
,
AMS
); Warnambool (
NMV
); Curdie’s Inlet (
NMV
);
New South Wales
:
Newcastle (
SAM
); Cronulla (
NMV
); Port Stephens (
NMV
); Bondi, Sydney (
NMV
); Curl Curl Beach, Sydney (
AMS
); Collaroy Beach, Sydney (
AMS
); C83049, Botany Bay (
AMS
); Terrigal (
AMS
); C67422, Maroubra Beach (
AMS
); Stockton Beach, Port Stephens (
AMS
); C40693, South Ocean Beach,Bermagui (
AMS
); C11240, Wollongong (
AMS
);
Tasmania
:
Tasmania (
WAM
,
NMV
,
NMNZ
);C12904, Flinders I. (
AMS
);
Queensland
:
Point Lookout, Stradbroke I. (
AMS
).
Lord Howe Island:
C59571 (
AMS
);
Norfolk Island
:
C59409 (
AMS
);
Kermadec Islands:
Raoul I. (
NMV
; C36654,
AMS
;
NMNZ
M202863, 12; M272663, many).
New Zealand
:
NW of Three Kings Islands (
NMNZ
M109274, 2; M308654, 8); Middlesex Bank, NW of Three Kings Islands (
NMNZ
M112779, 1);
37–39 km
SW of Great King, Three Kings Islands (
NMNZ
M094277, 1; M308655, 5; M308656, 1); W Norfolk Ridge, W of Cape Reinga (
NMNZ
M171012, 1; M171907, 3; M172329, 17); Cape Maria van Diemen (
AWM
30649); Spirits Bay (
NMNZ
M020279, 3); Ahipara Beach (
GNS
Suter colln, S2388, 7); Bayleys Beach, Dargaville (
NMNZ
M299995, 100); Cavalli Islands, Whangaroa (
NMNZ
M308653, 1); Maro Tiri I., Hen and Chickens Islands (
GNS
RM2672, 2); Bream Head, Whangarei (
AWM
18335); Leigh, N
Auckland
(
NMNZ
M087156, 20); Anawhata Beach, W
Auckland
(
GNS
RM5864, 60; RM6014, 5); Bethells Beach, W
Auckland
(
NMNZ
M016291, 12; M087157, 500; M308658, 40); Piha Beach, W
Auckland
(
GNS
RM5311, 100;
NMNZ
M087158, 300); Muriwai Beach, W
Auckland
(
GNS
RM332, 20;
AWM
18136;
NMNZ
M02762
, 50; M087159, 1000; M145116, 100); Whatipu, Manukau Harbour,W
Auckland
(
NMNZ
M087155, 20); Mokohinau Islands (
GNS
Suter colln, S1658, 7); Kaitoke Beach, Great Barrier I. (
NMNZ
M087153, 5); W coast Awhitu Peninsula, SW of Waiuku, W
Auckland
(
NMNZ
M277699, 5; M277701, many; M277703, many; M277705, 1; M277707, 1; M277709, many; M277740, 3; M277741, 4); Matakana I.,
Bay of Plenty
(
AWM
42757); Papamoa Beach,
Bay of Plenty
(
NMNZ
M120141, 4); Boulder Bay, Motuhora I., Whakatane (
NMNZ
M 033166, 20); Opotiki,
Bay of Plenty
(
GNS
RM331, 4); Te Kaha,
Bay of Plenty
(
NMNZ
M040065, 6); E of Te Araroa, East Cape (
GNS
RM4899, 3); Wainui Beach,
Gisborne
(
NMNZ
M308657, 4); Waimarama,
Hawke’s Bay
(
GNS
RM334, 11); Nukumaru Beach, Whanganui (
GNS
RM5626, 100); Whanganui (
GNS
RM4053, 1); Otaki Beach, W
Wellington
(
AWM
18344); Waitarere Beach, Levin (
GNS
RM2967, 42;
NMNZ
M011127, 11); Waikanae Beach, W
Wellington
(
NMNZ
M01154
, 15; M018897, 50; M160084, 100; M303125, 40; M308027, 400;
GNS
RM5852, 2360; RM5845, 300; RM5894, 100); Pukerua Bay, W
Wellington
(
NMNZ
M02760
, 30); Porirua Harbour mouth (
GNS
RM4041, 1); Titahi Bay, W
Wellington
(
NMNZ
M02759
, 20;
M06945
, 50); Lyall Bay,
Wellington
(
NMNZ
M087154, 7); Ocean Beach, Farewell Spit (
NMNZ
M023154, 9); Carters Beach, Westport (
GNS
RM5318, 20); Mason Bay, Stewart I. (
AWM
;
NMNZ
M019480, 15; M020278, 3);
Chatham Islands
(
AWM
16405;
NMNZ
M03853
, 2;
M05090
, 3;
GNS
Suter colln, S2387, 8); Kaingaroa Beach,
Chatham Islands
(
NMNZ
M110413, 8); Te Whakaru,
Chatham Islands
(
NMNZ
M013073, 2); beach NW coast of Mangere I.,
Chatham Islands
(
GNS
RM6013, 42).
Figure 34. Specimens of
Janthina exigua
Lamarck
and
Janthina umbilicata
d’Orbigny
; SEM.
(A–C
,
E–F)
Janthina exigua
, 2 specimens, GNS RM5852, Waikanae Beach, west Wellington, New Zealand; A, whole shell; B, sculpture on last whorl at apex of outer lip sinus; C, lateral view of protoconch; E, F, apical views of whole shell and protoconch.
(D
,
G–H)
Janthina umbilicata
, GNS RM
5312, Piha Beach, west Auckland, New Zealand; D, sculpture on last whorl at apex of outer lip sinus, to same scale as Fig. 34B; G–H, lateral views of whole shell and protoconch. Scale bars: A, E, G, 2 mm; B, D, 500 µm; C, H, 200 µm; F, 300 µm.
Distribution
. The writer is not aware of fossils of
Janthina exigua
.
Janthina exigua
is probably the most widely recorded of all living
Janthina
species. However, its distribution provides some surprises. It is the most common
Janthina
species in most beach strandings around
New Zealand
and southern
Australia
, whereas it is one of the least common species in the North Pacific, although it is among species recorded from
Japan
(as far north as Boso Peninsula, Honshu;
Higo
et al
. 1999: 173
). There seem to be few records from northern
Australia
, including
Queensland
.
Savilov (1969: 398–403)
described the distribution of
Janthina
species at 393 stations where
Janthina
was sampled by RV
Vityaz
in the Pacific.
J. exigua
was collected at only four of these 393 stations, all near the North Island of
New Zealand
. However, Savilov also noted that
Laursen (1953)
recorded
J. exigua
from further north in the South Pacific, to
10°S
, from
New Caledonia
east to Tahiti, in the southern Indian Ocean, and near Hawaii, and that
Fowler (1948
,
1949
) and
Wilson & Wilson (1956)
recorded
J. exigua
from the southern coasts of Britain. In contrast to all these observations,
Benson (1860: 406)
noted that “
I. exigua
was the most widely distributed species met with” during a voyage from
England
to Calcutta in the
Malcolm
, correctly pointing out that
I. capreolata
Montrouzier
is not separable. He first observed specimens two days before reaching Madeira (
Benson, 1860: 405
), and then observed specimens almost throughout the voyage. Benson’s careful distinctions between subtle forms, his comments on the synonymy of Reeve’s and other species names, and his references to publications by
Coates (1825)
,
Reeve (1858)
and
Mörch (1860)
show that his observations are very reliable.
Janthina exigua
occurs throughout the world tropical and temperate ocean, as far south as Orange Bay, Tierra del Fuego (
type
locality of
J. courcellei
) and Mason Bay, Stewart Island, southern
New Zealand
(listed above), but most reporters have described it as less common than other species in the northern Pacific and Indian Oceans.
Dimensions
. See
Table 8
.
Diagnosis
. Small, few specimens over
20 mm
high; spire tallest of all
Janthina
species, but height variable; whorls evenly and strongly convex, suture deeply impressed; sculpture of prominent, thin, closely spaced, commarginal axial ridgelets over entire teleoconch, c.
0.2–0.5 mm
apart at periphery of large specimens, angulated in conformity with sinus. Sinus occupying entire height of outer lip, deep, sharply V-shaped, apex in centre of lip. Most specimens deep, intense violet, some paler, very few with pinkish tinge. Lays ovate-triangular egg capsules on underside of float.
Remarks
. The small, deep violet species
Janthina exigua
is the most coarsely sculptured of living
Janthina
species, the only one with obvious, coarse axial ridges up to c.
0.5 mm
apart over the entire exterior of large shells, resembling the axial sculpture of
J. typica
,
J. chavani
and
J. krejcii
sp. nov.
and of a finely sculptured
Epitonium
species. Measurement of the spacing of the axial ridges on SEM images (
Fig. 34B
) showed that on this small specimen of
J. exigua
the ridges are c.
120–200 µm
apart at the periphery, whereas on the specimen of
J. umbilicata
examined by SEM (
Fig. 34D
) the ridges are only c.
30–40 µm
apart at the periphery. The axial lamellae of
J. exigua
also are considerably higher and more prominent than those of
J. umbilicata
. The apex of the outer lip sinus is at the periphery, i.e., in the centre of teleoconch whorls, and leaves a clear trace of the sinus apex around the centre of all whorls of tall-spired specimens. The consistently deep coloration is also a species character, the colour varying from deep reddish violet to (much more commonly) deep bluish violet, with a narrow paler zone beneath the suture in a few specimens. The radular teeth (
Laursen, 1953
: fig. 24) are similar to those of
J. umbilicata
, but have shorter bases, and some are less strongly hooked than those of
J. umbilicata
. The float (e.g.,
Laursen, 1953
: fig. 1;
Bennett, 1966
: pl. 9, fig. 2) is proportionally the longest and narrowest of all
Janthina
species, although a specimen photographed alive in northern
New South Wales
by Denis Riek (Brunswick Heads, NSW;
Fig. 5C
) demonstrates that the float of
J. umbilicata
is indistinguishable from that of
J. exigua
. The distinctiveness of
J. exigua
is attested by the remarkably few synonyms it has received in this vastly over-named genus.
Time range
. No fossil record; living only.