Bermudacaris australiensis, Anker & Komai, 2004
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publication ID |
https://doi.org/ 10.1080/0022293031000156312 |
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persistent identifier |
https://treatment.plazi.org/id/03CC87D5-FFFC-FFF0-7381-FB00FDCBF9ED |
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treatment provided by |
Carolina |
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scientific name |
Bermudacaris australiensis |
| status |
sp. nov. |
Bermudacaris australiensis View in CoL sp. nov. ( figures 5–7 View FIG View FIG View FIG )
Material examined. HOLOTYPE: ovigerous female (CL 2.7 mm, TL ca 9 mm), NTM Cr-000476, north-west shelf, Western Australia, 19‡54.0’S, 117‡52.2’E, depth 38 m, 7 April 1983, FRV ‘ Soela’, P. Blyth, coll.
Description. Carapace smooth; rostrum very short, broad, distally rounded, reaching level of antero-lateral margin of carapace ( figure 5A View FIG ); rostral carina and orbital teeth absent; orbital concavity very shallow; antero-lateral margin continuous with ventro-lateral margin without formation of pterygostomian angle; cardiac notch conspicuous ( figure 5C View FIG ). Eye-stalks exposed dorsally and laterally ( figure 5A, B View FIG ), mesial margins not parallel and separated from each other by median space; cornea well pigmented, occupying most of distal third of eye-stalk ( figure 5A View FIG ).
Antennular peduncle with second segment as long as visible portion of first segment; stylocerite short, not appressed, not reaching distal margin of first segment, tip acute ( figure 5A View FIG ); ventro-mesial carina on first segment low, terminating anteriorly in acute tooth ( figure 5D View FIG ); outer flagellum not subdivided. Antenna with basicerite bearing ventro-lateral tooth; carpocerite slender, twice as long as scaphocerite and exceeding distal margin of antennular peduncle ( figure 5B View FIG ); scaphocerite rectangular-oval in general outline, with nearly straight lateral margin, nearly reaching distal margin of second segment of antennular peduncle, with strong disto-lateral tooth slightly over-reaching distal margin of rounded blade
( figure 5A View FIG ). Mouthparts typical for Alpheidae ( figure 6 View FIG A–E). Second maxilliped with bilobed
podobranch ( figure 6E View FIG ). Third maxilliped ( figure 6F View FIG ) elongated, reaching far beyond distal end of antennal peduncle; antepenultimate segment robust; ultimate segment armed with strong spines on distal half of superior margin; lateral plate on coxa conspicuous, rounded oval in shape ( figure 6G, H View FIG ); exopod short, not reaching distal third of antepenultimate segment; strap-like epipod and single arthrobranch present.
First pereopods (chelipeds) robust, symmetrical, carried extended, elevated; ischium with two curved spines on superior margin ( figure 7A, B View FIG ); merus stout, margins straight, ventral margin distally with rows of setae ( figure 7D View FIG ); carpus robust, relatively large, cup-shaped ( figure 7D View FIG ); chela laterally compressed; palm oval-shaped, depressed proximal to carpo-propodal articulation, otherwise without sculpture; fingers as long as palm, dactylus in ventral to ventro-lateral position ( figure 7A, C View FIG ), slightly longer than pollex, cutting edges unarmed ( figure 7C View FIG ).
Second pereopods missing. Third pereopod ( figure 6I View FIG ) robust, compressed laterally; ischium unarmed; merus unarmed; carpus armed with small disto-ventral spine; propodus armed with four or five slender spines; dactylus subconical, slightly curved, slightly less than half as long as propodus, tip acute. Fourth and fifth pereopods missing.
First to fifth abdominal somites with pleura rounded ventrally and covering only most basal portions of pleopod coxae. Sixth somite without articulated flap, postero-lateral projection rounded; preanal plate rounded. Telson obviously dissected (detached at basis), but missing.
Uropod with endopod nearly as long as exopod; exopod with weak posterolateral tooth and small movable spine arising just mesial to postero-lateral tooth, diaeresis weakly developed, laterally sinuous ( figure 5E View FIG ).
Gill formula as given for genus by Anker and Iliffe (2000): pleurobranchs on first to fifth pereopods; single arthrobranch above third maxilliped; podobranch on second maxilliped; exopods on all three maxillipeds; strap-like epipods (mastigobranchs) on first maxillipeds to fourth pereopods; setobranchs on first to fifth pereopods.
Colour in life. Unknown.
Size. Small species, ovigerous female 2.7 mm in CL, about 9 mm in TL.
Distribution and habitat. Presently known only from North-West Shelf off Western Australia, where the unique specimen was dredged from the depth of 38 m.
Etymology. The specific name of the species refers to the collection locality in a broader geographic sense, the continent of Australia.
Discussion. The holotype of this new species is somewhat damaged. The second, fourth and fifth pereopods and the telson are missing; most of the preserved pereopods were removed at the basis-ischium articulation; the palm of the left cheliped is damaged, too. Nevertheless, most body parts and the appendages that are important to make a definite identification of the generic and specific status are present. The new species is assigned with little doubt to Bermudacaris , based on the following features: (1) rostrum short, rounded; (2) podobranch present on the second maxilliped; (3) chelipeds symmetrical, with dactyli situated in ventral position; (4) ventro-mesial carina of the first antennular segment armed with an acute tooth distally; (5) ventral margin of the propodus of the third pereopod bearing a row of spines; (6) dactylus of the third pereopod conical, simple; and (7) mesial margins of eye-stalks not parallel and not juxtaposed. The combination of these features would not allow the new species to be placed in either Automate or Coronalpheus .
Bermudacaris australiensis sp. nov. is the second species described in this genus, and can be easily distinguished from the type species B. harti by the much more robust chelipeds (especially the more stout merus); more robust third to fifth pereopods, lacking ischial spine; the shorter stylocerite; and the darkly pigmented cornea of the eye. Because of the presence of the corneal pigmentation and the absence of an ischial spine on the third pereopod in B. australiensis sp. nov., the original diagnosis of Bermudacaris is slightly modified (see below).
The habitat of B. australiensis sp. nov. remains unknown, all we know is that the specimen was dredged from 38 m deep and that it is apparently a marine benthic species. The discovery of B. australiensis sp. nov. and the recent finding of what appears to be a third, possibly yet undescribed species of Bermudacaris in an anchialine sinkhole on Mallorca Island in the Mediterranean Sea ( T. M. Iliffe and D. Jaume, personal communication) indicates that the genus is more widely distributed in the world oceans.
| NTM |
Northern Territory Museum of Arts and Sciences |
| T |
Tavera, Department of Geology and Geophysics |
No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.