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Promachoteuthis sloani, a new species of the squid familyPromachoteuthidae (Mollusca: Cephalopoda)
Richard E. Young, Michael Vecchione, and Uwe Piatkowski
(REY) Dept. of Oceanography, University of Hawaii, Honolulu, Hawaii 96822, U.S.A.,
e-mail: [email protected];
(MV) Systematics Laboratory, National Marine Fisheries Service, National Museum of Natural
History, Washington, D.C. 20013-7012, U.S.A., e-mail: [email protected];
(UP) Leibniz-Institut fur Meereswissenschaften, IFM-GEOMAR, Kiel, Germany,
e-mail: [email protected]
Abstract.—We describe Promachoteuthis sloani, a new species of oegopsid
squid in the family Promachoteuthidae. The new species is based on two
specimens with the following characters that are unique within the family:
each tentacle with two series of complex papillae in the proximal 80%, andeach tentacle with pigmented ridges dorsolateral to the papillae that break
into papillae distally.
Promachoteuthids are poorly known
squids taken from temperate to near
Polar regions of the Atlantic and Pacific
oceans (Roper & Young 1968). They are
weakly muscled squids thought to reside
at bathypelagic depths; all have been
taken in open trawls that reached maxi-
mum depths between 1400 and 3650 m.
The smallest known specimen has a man-
tle length (ML) of 10.5 mm (form B of
Young & Vecchione 2003a), and the
largest, 102 mm ML (the new species
described herein, paratype). One female
(form D of Young & Vecchione 2003a)
was mature at 42 mm ML whereas the
large paratype female is immature. Pro-
machoteuthids mostly have large fins,
peculiar tentacular clubs, small eyes with
an eye opening that may be a simple pore,
and lenses covered by translucent eyelids
(i.e., pseudocorneas). Currently, only
a single species (P. megaptera) is named
(Okutani 1983, Voss 1992), but five
additional forms are known (Salcedo-
Vargas & Guerrero-Kommritz 2000,
Young & Vecchione 2003b). Four of the
five forms are known from single speci-
mens. Here we present diagnoses and
brief descriptions of one of the forms,
based on the capture of a second speci-
men in virtually perfect condition. Addi-
tional information is available on the
world-wide web at: http://tolweb.org/
Promachoteuthis_sloani/19529.
Materials and Methods
The holotype (Fig. 1, Bergen Musem
cat. no. ZMBN 77622), an immature
female, 58 mm ML, was captured in the
North Atlantic Ocean by the R/V G. O.
SARS (MAR-ECO cruise super station
14, local station 341) at 53u059N, 36u469W
in a trawl that fished to a maximum depth
of 2792 m, in 2004. The paratype (Fig. 2,National Museum of Natural History cat.
no. USNM 1086443), an immature fe-
male, 104 mm ML, was taken at the R/V
Walter Herwig station 714, 46u009N,
15u499W, North Atlantic Ocean, in a trawl
that fished to 2650 m, in 1973.
Systematics
Promachoteuthidae Naef, 1912
Diagnosis.—Oegopsid squids with un-expanded tentacular clubs bearing nu-
PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON119(2):287–292. 2006.
merous suckers in irregular series. Clubswithout keels, terminal pads, proximallocking apparatus, or protective mem-branes. Oval funnel locking-apparatuswithout interior bumps (tragus and anti-tragus). Head and eyes extremely small;eye lenses covered by translucent mem-branes (pseudocorneas). Ink sac, anal
flaps, and photophores absent. Ventralbuccal-crown connectives connect to theventral margins of arms IV.
Promachoteuthis Hoyle, 1885.
Monogeneric family. See family diag-
nosis.
Fig. 1. Promachoteuthis sloani. Holotype, various views of the recently captured squid before fixation:
A, predominately ventral view; B, dorsal view; C, side view. Note dark pigmentation, small head, thick
tentacles and numerous large papillae on tentacles.
288 PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON
Promachoteuthis sloani, new species
Promachoteuthis sp. A: Toll, 1982.—
Voss, 1992.
Diagnosis.—Mantle free from head in
nuchal region. Arm suckers in 3–4 series
in central region of arm. Fin length ca.
60–70% ML. Tentacles bordered by
complex papillae and pigmented dorso-
lateral ridges that break up into papillae
distally.
Description.—Each tentacle with two
series of long papillae (Fig. 3a) near oral
midline at tentacle base but diverging to
be lateral to club; papillae often with
stubby branches in holotype but becom-
ing flattened, highly branching; some
papillae merging to become short com-
plex membranes in paratype (Fig. 3b).
Darkly pigmented ridges present along
lateral margins of aboral surface of each
tentacle (Fig. 1a, c); distally the ridges
break into small papillae. Pigmented
ridges in holotype extend approximately
over proximal 80% of tentacle; in para-
type pigmented ridges less prominent,
restricted to middle third of tentacle.
Club suckers on white stalks emerging
from small, white, circular patches on
pigmented club (Fig. 3a). Narrow, elon-
gate flaps scattered between suckers in
paratype but flaps absent in holotype.
Fig. 2. Promachoteuthis sloani. Paratype, drawings of preserved squid: A, dorsal view; B, ventral view.
Drawings by Keiko Hiratsuka Moore, National Marine Fisheries Service.
VOLUME 119, NUMBER 2 289
Fig. 3. Promachoteuthis sloani. A, oral view of the tentacle, holotype; B, oral view of tentacle, paratype;
C, oral view of large club sucker, paratype; D, oral view of large arm sucker, paratype; E, lateral view of eye,
holotype after preservation; F, lateral view of lower beak of paratype, rostral length 9 mm; G, lateral view of
upper beak of paratype, rostral length 18 mm. In Fig. 3e upper arrow points to eye opening, middle arrow to
pupil and lower arrow to lens. Note large difference in shape of papillae that line tentacle between Fig. 3a
and b; difference presumably due to squid size.
290 PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON
Club suckers with irregular margins on
inner rings without well-defined teeth
(Fig. 3c). Club diameter narrows some-
what abruptly distally, where suckers
become more densely packed, forming
a nearly cylindrical distal end.
Arms thick, without keels and with
low, thick protective membranes. Arms
with three or four rather irregular sucker
series in mid-region, sometimes appearing
as up to six series. Arm suckers with
smooth inner rings having appearance of
fused, truncated teeth (Fig. 3d).
Fins large. Large anterior lobes pres-
ent; posterior lobes absent in holotype,
but small, distinct posterior lobes present
in paratype.
Head extremely small with small eyes
bulging laterally from head. Eyelid form-
ing small, circular opening. Eyelid over
lens opaque but with somewhat clearer
central region (pseudocornea). Lower
beak (Fig. 3f) without lateral wall fold
or ridge; with convex margin on inner jaw
edge. Upper beak (Fig. 3g) with short
rostrum; with hood margin high above
lateral wall crest.
General pigmentation purple-brown
(Fig. 1). Pigment in epithelial cells not
chromatophores; chromatophores appar-
ently absent. Pigmentation light to absent
over eye lenses, aboral base of tentacles
and arms IV, distal ends of tentacles;
white line down aboral midline of tenta-
cles over proximal 60% of tentacle length.
Surfaces within the mantle cavity heavily
pigmented.
Measurements(mm).—Holotype: Man-
tle Length (ML) 58, Mantle Width (MW)
ca. 18, Head Width (HW) 13, Fin Length
(FL) 33, Fin Width (FW) 54, Arm I 32,
Arm II 36, Arm III 31, Arm IV 35,
Tentacle Length (TL) 60, Club Length
(CL) 37. Paratype: ML 102, FL 70, FW
121, Arm I 92, Arm II 93, Arm III 88,
Arm IV 90, TL 148, CL 71, Gladius
Length 93.5. Gladius Width (GW) ante-
rior 7.4. GW posterior 10.3 (gladius
measurements from Toll, 1982).
Etymology.—Promachoteuthis sloani is
named in honor of the A. P. Sloan
Foundation in recognition of its generous
support of the Census of Marine Life
(CoML) and its MAR-ECO Program
under which the holotype was captured.
The CoML has done much to promoteour understanding of oceanic biogeogra-
phy and biodiversity of the oceans in
general.
Discussion
Promachoteuthis sloani differs from the
only other named species in the family by
the large number of sucker series on the
arms (three to four or more vs two) and
its peculiar tentacles, especially the pres-
ence of the papillae-series of the tentacles
and the lack of proximal pigment-bands.It differs from all four unnamed forms by
the free dorsal mantle margin in the
nuchal region, among other characters
(Young & Vecchione 2003a).
Little can be inferred about the biology
of this species, but the very short rostra
on the beaks suggest a powerful masti-
cating ability.
Acknowledgments
We thank the science team, officers and
crew of the R/V G. O. SARS, MAR-ECO
cruise, on which the holotype was cap-
tured and especially Odd Aksel Bergstad
for his leadership of the project. C. F. E.Roper collected the paratype. We also
thank Angel Guerra and an anonymous
reviewer for their comments on the
manuscript.
Literature Cited
Hoyle, W. E. 1885. Narrative of the Challenger
Expedition. Report on the scientific results of
the voyage of H. M. S. Challenger during the
years 1873–1876, Narrative 1(1):269–274, 4
figures.
Naef, A. 1912. Teuthologische Notizen. 1. Die
familien Myopsiden.—Zoologischer Anzeiger
39:241–244.
VOLUME 119, NUMBER 2 291
Okutani, T. 1983. Rare and interesting squid from
Japan. VIII. Rediscovery of Promachoteuthis
megaptera Hoyle, 1885 (Oegopsida: Proma-
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Roper, C. F. E., & R. E. Young. 1968. The family
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Voss, N. A. 1992. Family Promachoteuthidae.—
Smithsonian Contributions to Zoology 513:
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Young, R. E., & M. Vecchione. 2003a. Promachoteu-
thidae. http://tolweb.org/Promachoteuthidae/
19454
———, & ———. 2003b. Promachoteuthis sp. A.
http://tolweb.org/Promachoteuthis_sloani/
19529
Associate Editor: Stephen L. Gardiner
292 PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON