Memoirs of the Museum of Victoria 57( I ): 57-69 ( 1 998)
A REVIEW OF THE GENUS LEONTOCARIS (CRUSTACEA: CARIDEA: HIPPOLYTIDAE)
WITH DESCRIPTIONS OF THREE SPECIES FROM SOUTHEASTERN AUSTRALIAN
SEAMOUNTS AND SLOPE
Joanne Taylor and Gary C. B. Poore
Department of Crustacea, Museum of Victoria, 71 Victoria Crescent, Abbotsford, 3067, Australia
(
[email protected] and
[email protected])
Abstract
Taylor, J. and Poore, G.C.B., 1998. A review of the genus Leontocaris (Crustacea: Caridea:
Hippolytidae) with descriptions of three species from southeastern Australian seamounts and
slope. Memoirs of the Museum of Victoria 57: 57-69.
The genus Leontocaris and its species are diagnosed. Leontocaris bulga sp. nov.
and Leontocaris yarramundi sp. nov. are described and illustrated, compared with four
other species of the genus, and a key for their identification provided. New observations of
L. amplectipes Bruce. 1990 are made from new material from seamounts southeast of
Tasmania.
Introduction
Leontocaris Stebbing, 1905, a small genus of
hippolytid caridean shrimps, comprises
L, paulsoni Stebbing, 1905 from 240-265 m
off South Africa (Barnard, 1950), L. lar Kemp,
1906 from 1000-1300 m from the northwest
Atlantic Ocean off Ireland, L. pacificus
Zarenkov, 1976 from 680-700 m from the
Pacific Ocean off western South America and
L. amplectipes Bruce, 1990 from 1000 m off
southeastern Australia. Bruce (1990) reviewed
the genus and provided a key to three species. He
discussed the possible association of the species
with cnidarians.
A small collection of hippolytid shrimps from
seamounts (750-1450 m depth) southeast
of Tasmania contains additional specimens
of Leontocaris belonging to three species.
Here, two new species are described, one on the
basis of five specimens, and another on the basis
of a carapace and anterior limbs. We take
the opportunity to rediagnose L. amplectipes
in the light of new material and the other
species so far described. All species of
Leontocaris possess a tympanum or thinning
of the exoskeleton on the inner surface of the
propodus of pereopod 2. The size of this varies
between species and may play a part in extension
of the folded limb.
Abbreviations are: cl., carapace length; NMV,
Museum of Victoria, Melbourne; TM, Tasmanian
Museum, Hobart, where material is lodged. In
habitus drawings pereopods were drawn after
separation from the body and flattened.
Leontocaris
1950: 699.
Leontocaris Stebbing
Stebbing, 1905: 98-99.— Barnard,
Diagnosis. Pereopods without arthrobranchs.
Mandible with incisor and 1-or 2-articulate palp.
Maxilliped 3 without exopod or epipod. Epipods
present only on maxilliped 1 and 2. Rostrum
half as long or as long as carapace. Supraorbital
spine absent. Pereopod 1 slender, carpus
elongate. Pereopod 2 strongly asymmetrical,
carpus 4-segmented. Major pereopod 2 with
elongate and robust propodus and enlarged, chop-
per-shaped dactylus. Pereopods without arthro-
branchs. Maxillipeds 2-3 and pereopods 1-4 with
pleurobranchs.
Remarks. Barnard's (1950) generic diagnosis
stated that the mandibular palp is small and
uniarticulate. We amend that to allow the 2-
articulate palp seen in Leontocaris bulga sp. nov.
Kemp (1910) reported a thin-walled sausage-
shaped structure in the groove on the inner
margin of the propodus of the major pereopod 2.
This area of thin exoskeleton or tympanum is
surrounded by what appear to be minute villi. The
long proximal segment of the carpus lies in this
groove when the limb is folded and is held in
place by the merus which interacts with the
groove. The size and shape of the tympanum dif-
fers between species, being elongate in most but
only a small circular structure in L. amplectipes.
What function, if any, this structure plays in the
assumed rapid extension of the pereopod remains
to be investigated.
57
Localities extracted from OCR text.
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