Cyclocaris lowryi Horton & Thurston 2014
- Dataset
- A revision of the bathyal and abyssal necrophage genus Cyclocaris Stebbing, 1888 (Crustacea: Amphipoda: Cyclocaridae) with the addition of two new species from the Atlantic Ocean
- Rank
- SPECIES
- Published in
- Horton, Tammy, Thurston, Michael H. (2014): A revision of the bathyal and abyssal necrophage genus Cyclocaris Stebbing, 1888 (Crustacea: Amphipoda: Cyclocaridae) with the addition of two new species from the Atlantic Ocean. Zootaxa 3796 (3): 507-527, DOI: 10.11646/zootaxa.3796.3.6
Classification
- kingdom
- Animalia
- phylum
- Arthropoda
- class
- Malacostraca
- order
- Amphipoda
- family
- Lysianassidae
- genus
- Cyclocaris
- species
- Cyclocaris lowryi
description
(Figures 4 – 7)
description
Description. Holotype female, 17.1 mm. Head: exposed, deeper than long, rather short dorsally but telescoped into peraeonite 1; lateral cephalic lobe moderate, rounded; rostrum very small. Eyes: four, pigmented, lacking ommatidea, pigment lost in alcohol; upper, small, sub-oval; lower, larger, sub-oval, in cephalic lobe. Antenna 1: short, 0.15 x body; peduncular article 1 short; peduncular article 2 short, 0.3 x article 1; peduncular article 3 short, 0.3 x article 1; primary flagellum 10 - articulate; accessory flagellum long, 0.6 x primary flagellum, five-articulate, article 1 as long as articles 2 – 5 combined; callynophore strong two-field; calceoli absent. Antenna 2: short, 1.65 x antenna 1; peduncle with brush setae, not geniculate; peduncle article 1 not greatly enlarged; peduncle article 3 short, 0.4 x article 4; articles 4 and 5 not enlarged; flagellum well developed, 20 - articulate. Mouthpart bundle: subquadrate. Epistome and upper lip: separate, rounded, weakly produced, epistome weakly dominant. Mandible: incisor smooth, weakly convex, with minute ventral hook; lacinia mobilis present on left mandible only, a slender peg minutely bifurcate distally; accessory setal rows with seven simple robust setae and many setules; molar a setose, proximally directed, non-triturating flap; palp attached distally; article 1 short, broader than long; article 2 slender, length 4.0 x breadth, with about 20 A 2 setae on distal 0.4; article 3 slender, tapering, length 4.2 x breadth, with 25 D 3 setae and three E 3 setae. Lower lip: outer plates gaping, setose marginally, inner plates apparently absent (but see below), molar processes prominent, rounded distally. Maxilla 1: inner plate slender, with nine pappose setae along inner margin; outer plate with 11 setal-teeth in a 7 / 4 crown arrangement, ST 1 – 5 weakly one-, two- or three-cuspidate, ST 6 – 7 simple, ST 7 displaced from ST 6, STA – C obscurely cuspidate, STD simple; palp large, two-articulate, article 1 short, article 2 broadened with three short robust setae on tridentate apical margin, one flag seta, two subapical robust setae, and one pappose seta on dorsal margin. Maxilla 2: inner plate short, 0.67 x length of outer plate, tapering, with rows of marginal and submarginal pappose and simple setae; outer plate with marginal and apical stout and slender setae. Maxilliped: inner plate large, subtriangular, with three very small nodular spines on strongly oblique apical margin, oblique setal row strong, with ten pappose setae; outer plate large, subovate, with 19 pappose setae apically and laterally, no robust setae, and about 20 minute nodular setae on medial margin; palp large, four-articulate, article 2 slender, length 2.7 x breadth, article 3 long, slender, length 2.7 x width, dactyl well-developed, slender, with three short subterminal setae and two rows of minute denticles on the medial surface. Gnathopod 1: simple; coxa vestigial, anterior margin straight, posterior margin convex; basis long, slender, length 5.8 x breadth, anterior margin straight, lacking setae, posterior margin straight, with one short seta; ischium long, length 3.7 x breadth; carpus very long, subquadrate, lacking posterior lobe, margins subparallel, length 4.1 x. breadth, 1.3 x length of propodus; propodus long, subquadrate, length 4.8 x breadth, margins weakly convergent, anterior weakly convex, posterior weakly concave, palm absent; dactylus simple, length 0.29 x propodus, with subterminal setae. Gnathopod 2: subchelate; coxa vestigial, subrectangular; basis long, slender, curved, anterior margin convex, length 6.1 x breadth; ischium long, length 3.3 x breadth; carpus very long, length 5.7 x breadth, margins subparallel, posterior margin straight, 2.3 x length of propodus; propodus subovate, length 3.0 x breadth, setulose, palm slightly acute, weakly convex, serrate distally; dactylus inserted near middle of propodus distal margin, reaching corner of palm. Peraeopod 3: coxa large, weakly expanded, broadly rounded distally; basis straight, margins subparallel; merus narrowly produced anterodistally, extending 0.37 x length of carpus; dactyl slender, curved, 0.43 x length of propodus. Peraeopod 4: coxa as deep as wide, posteroventral lobe short, broadly rounded; distal articles as in peraeopod 3. Peraeopods 5 – 7: subequal in length. Peraeopod 5: coxa unequally bilobate, posterior lobe deeper, strongly produced posteriorly; basis expanded, subovate, posterior margin convex, posterodistal margin broadly rounded; merus slender, produced posterodistally, extending 0.23 x length of carpus, propodus slender, length 6.8 x breadth; dactylus slender, curved, 0.33 x length of propodus. Peraeopod 6: coxa bilobate, posterior lobe deeper, expanded posteriorly; basis expanded, posterior margin convex, posterodistal lobe broadly rounded; merus slender, posterior margin weakly convex, weakly produced. Peraeopod 7: coxa posterior lobate; basis expanded, tapering distally, posterior margin weakly convex, posterodistal lobe narrowly rounded; merus slender, weakly produced posterodistally. Gills: gnathopod 2 to peraeopod 7; peraeopod 7 gill large. Oostegites: gnathopod 2 to peraeopod 5. Pleonites 1 to 3: not carinate. Epimeron 1: broadly rounded ventrally. Epimeron 2: subrectangular; anteroventral corner rounded, posteroventral corner with acute tooth, posterior margin sinuous, ventral margin setose. Epimeron 3: expanded distally; anteroventral corner rounded, posteroventral corner with subacute tooth, posterior margin concave, ventral margin setose. Urosome: urosomite 1 with low rounded boss; urosomite 2 nearly occluded dorsally; urosomite 3 produced posterolaterally, markedly concave dorsally, with strong dorsolateral flanges. Uropod 1: peduncle with 12 dorsolateral robust setae and nine dorsomedial robust setae; inner ramus 0.57 x length of peduncle, with three dorsomedial setae; outer ramus 0.90 x inner ramus, with three dorsolateral setae. Uropod 2: peduncle with four dorsolateral robust setae and two dorsomedial robust setae; inner ramus 1.1 x length of peduncle, with two lateral and five medial setae; outer ramus 0.72 x inner ramus, with four lateral and four medial setae. Uropod 3: peduncle short, with four dorsomedial setae; rami subequal, lanceolate, with plumose setae on medial margins; inner ramus 1.6 x peduncle, with five lateral and two medial robust setae; outer ramus 2 - articulate, article 2 length 0.31 x article 1, article 1 with four lateral and one medial robust setae. Telson: long, lobes tapering, length 1.8 x breadth, cleft 81 %; lobes with four dorsolateral robust setae, apices notched with one robust seta. Male. Similar to female except for calceoli on both antennae and a longer callynophore.
discussion
Remarks. C. lowryi differs from C. tahitensis and C. guilelmi by the rounded triangular eyelobe. For characters separating C. lowryi from C. franki, see under the latter species. The lower lip as figured here agrees closely with the illustration of Chevreux (1935) and appears to lack inner lobes. However, the lower lip of the holotype was damaged during dissection. An examination of other specimens shows that inner lobes are present but are very small; much smaller than those shown for C. guilelmi by Barnard (1959). They project dorsally, i. e. perpendicular to the outer lobes, and are fused with separated, rounded apices. Most material has come from baited traps set at abyssal depths, but individuals occupy the benthopelagic zone (present material; Thurston, 1990).
distribution
Distribution. Atlantic Ocean, 8 – 49 ˚ N. Guiana, Cape Verde, Madeira, Horseshoe, Iberian and Porcupine Abyssal Plains, Portuguese canyons, 3600 – 5432 m, benthic and abyssopelagic (present material; Thurston, 1990).
etymology
Etymology. This species is named for Jim Lowry in recognition of his huge contribution to our knowledge of amphipods in general and lysianassoids in particular.
materials_examined
Type material. Holotype: preparatory female, 17.1 mm, carcass and 6 slides; Sta. 12600 # 44, DEMAR, 9 - 10 October 1993 (bottom time 10 hours 45 minutes), 21 º 05.2 ’ N 31 º 06.6 ’ W, 4540 m, Cape Verde Abyssal Plain; NHMUK 2014. 437. Allotype: adult male, 12.6 mm; Sta. 12600 # 46, DEMAR, 10 – 11 October 1993 (bottom time 22 hrs 57 mins), 21 º 01.2 ’ N 31 º 13.0 ’ W, 4555 m, Cape Verde Abyssal Plain; NHMUK 2014. 438. Paratypes: Sta. 12600 # 44, same data as holotype; 124 specimens, NHMUK 2014. 439 – 448. Sta. 12600 # 46, same data as allotype; 263 specimens, NHMUK 2014. 449 – 458. Additional material examined. Specimens retained in the Discovery Collections, National Oceanography Centre, Southampton. 8524 # 1, BN 1.5 / 5 C, 28 June 1974, 20 º 45.5 ’ N 22 º 42.5 ’ W – 20 º 46.6 ’ N 22 º 44.3 ’ W, 4412 m, Cape Verde Abyssal Plain, 1 specimen. 9541 # 18, RMT 8, 18 April 1977, 20 º 18.5 ’ N 21 º 41.2 ’ W – 20 º 20.8 ’ N 21 º 53.0 ’ W, 3970 – 4020 m (0 – 20 metres above bottom), Cape Verde Abyssal Plain, 1 specimen. 9541 # 19, RMT 8, 18 April 1977, 20 º 19.7 ’ N 21 º 51.3 ’ W – 20 º 18.4 ’ N 21 º 40.5 ’ W, 3970 – 4040 m (0 – 20 mab), Cape Verde Abyssal Plain, 1 specimen. 9629 # 1, TRAP B, 27 – 28 October 1977 (bottom time 26 hrs 12 mins), 35 º 47.4 ’ N 13 º 12.5 ’ W, 4850 m, Horseshoe Abyssal Plain, 2 specimens. 52216 # 5, AMPHT, 23 – 25 June 1985 (bottom time 35 hrs 05 mins), 48 º 50.02 ’ N 16 º 30.42 ’ W, 4842 m, Porcupine Abyssal Plain, 2 specimens. 11261 # 56, RMT 8 M / 3, 4 July 1985, 31 º 14.7 ’ N 25 º 14.6 ’ W – 31 º 17.6 ’ N 25 º 18.3 ’ W, 5415 – 5425 m (25 – 11 mab), Madeira Abyssal Plain, 1 specimen. 11261 # 64, RMT 1 M / 2, 6 July 1985, 31 º 19.2 ’ N 25 º 21.4 ’ W – 31 º 24.3 ’ N 25 º 21.3 ’ W, 5385 – 5410 m (48 – 25 mab), Madeira Abyssal Plain, 1 specimen. 11262 # 17, BN 1.5 / 3 M SBN, 17 July 1985, 31 º 13.3 ’ N 25 º 14.4 ’ W – 31 º 11.5 ’ N 25 º 09.6 ’ W, 5432 m, Madeira Abyssal Plain, 1 specimen. 11262 # 19, BN 1.5 / 3 M SBN, 18 July 1985, 31 º 19.8 ’ N 25 º 29.0 ’ W – 31 º 34.0 ’ N 25 º 26.9 ’ W, 5432 m, Madeira Abyssal Plain, 5 specimens. 12174 # 20, BSNACK, 18 – 23 August 1990 (bottom time 111 hrs 34 mins), 31 º 07.6 N 21 º 10.0 ’ W, 4941 m, Madeira Abyssal Plain, 9 specimens. 52701 # 35, DEMAR, 22 – 23 May 1991 (bottom time 20 hrs 21 mins), 48 º 48.5 ’ N 16 º 23.6 ’ W, 4843 m, Porcupine Abyssal Plain, 1 specimen. 12600 # 14, BSNACK, 1 – 7 October 1993 (bottom time 138 hrs 50 mins), 21 º 01.1 ’ N 31 º 10.8 ’ W, 4549 m, Cape Verde Abyssal Plain, many specimens. 12600 # 41; BSNACK, 9 – 14 October 1993 (bottom time 130 hrs 4 mins), 21 º 04.6 ’ N 31 º 11.6 ’ W, 4615 m, Cape Verde Abyssal Plain, 19 specimens. 12600 # 60; DEMAR, 14 – 16 October 1993 (bottom time about 40 hours, soluble link parted prior to proposed release), 21 º 05.1 ’ N 31 º 12.9 ’ W, 4569 m, Cape Verde Abyssal Plain, many specimens. 13077 # 4, NIOZ LANDER, 14 – 18 March 1997 (bottom time 79 hrs 44 mins), 48 º 55.82 ’ N 16 º 35.25 ’ W, 4844 m, Porcupine Abyssal Plain, 2 specimens. 13077 # 35, NIOZ LANDER, 19 – 23 March 1997 (bottom time 82 hrs), 48 º 58.10 ’ N 16 º 24.93 ’ W, 4845 m, Porcupine Abyssal Plain, 2 specimens. 15734 # 1, DEMAR, 1 – 2 August 2005, (bottom time 21 hrs 28 mins), 39 º 29.78 ’ N 09 º 57.89 ’ W, 3600 m, Nazaré Canyon, 1 specimen. 15741 # 1, DEMAR, 4 – 5 August 2005 (bottom time 24 hrs 22 mins), 39 º 34.95 ’ N 10 º 16.5 ’ W, 4286 m, Nazaré Canyon, 25 specimens. 56839 # 1, VET, 4 – 5 May 2006 (bottom time 24 hrs 12 mins), 38 º 06.57 ’ N 09 º 58.18 ’ W, 4445 m, Setúbal Canyon, 1 female specimen. 56847 # 1, DEMAR, 7 – 8 May 2006 (bottom time 24 hrs 34 mins), 39 º 35.50 ’ N 10 º 19.00 ’ W, 4403 m, Nazaré Canyon, 3 specimens.
Name
- Synonyms
- Cyclocaris undetermined
- Homonyms
- Cyclocaris lowryi Horton & Thurston 2014