The Pachynidae fam. nov. (Crustacea: Amphipoda: Lysianassoidea) 3246
Lowry, J. K.
Stoddart, H. E.
Zootaxa
2012
2012-03-23
3246
1
1
69
4BQL5
Lowry & Stoddart, 2012
Lowry & Stoddart
2012
[151,445,1620,1646]
Malacostraca
Pakynidae
Pachychelium
Animalia
Amphipoda
31
32
Arthropoda
species
fucaensis
sp. nov.
( Figs 21, 22)
Type material. HOLOTYPE, sex not known, 2.7 mm, NMCC 1988-0047, Clover Point, Juan de Fuca Strait, Vancouver Island, British Columbia, Canada, 48°23'01"N 123°21'46"W, 85 m, 28 August 1976, G.W. O'Connell, stn GWO W158A. PARATYPES: 1 specimen, LACM 77- 283.2, ridge south of Santa Rosa Island, Santa Cruz Basin, off California, U.S.A., 33°49.0'N 119°59.9'W, 103–108 m, bio-box, 1977–78, Bureau of Land Management Survey, RV Thomas G. Thompson, stn 80835 BF.5; 1 specimen, LACM 77- 284.1, south of Santa Cruz Island, Santa Cruz Basin, off California, U.S.A., 33°46.2'N 119°50.9'W, 222–271 m, bio-box, 1977–78, Bureau of Land Management Survey, RV Thomas G. Thompson, stn 80929 BF.1. Typelocality. Clover Point, Juan de Fuca Strait, Vancouver Island, British Columbia, Canada, 48°23'01"N 123°21'46"W, 85 mdepth.
Etymology.Named for the typelocality, Juan de Fuca Strait. Diagnostic description. Headlateral cephalic lobe large, narrowly rounded; ventral margin curved. Antenna 1peduncular article 1 without posterodistal spine; accessory flagellum 2-articulate, article 1 long; flagellum with weak 1-field callynophore in specimen of unknown sex. Mandiblelacinia mobilis absent; lamina dentata absent; accessory setal row absent; molar absent; palp attached distally; palp article 2 broad, as long as article 3; article 3 tapered distally. Maxilla 1outer plate with 4 setal-teethin 4/0 or 3/1 arrangement, setal-teeth smooth; palp absent. Maxillipedinner plate absent; outer plate medium size; palp 3-articulate (article 4 absent), article 3 length 2.2 × breadth. Gnathopod 1subchelate; ischium smaller than propodus, not swollen posteroproximally; carpus extremely compressed; propoduslength about 1.8 × breadth, posterior margin extremely reduced, with produced posterodistal corner, with simple robust seta; dactylus over-reaching palm. Gnathopod 2palm minute, obtuse. Pereonite 4without dorsal spines. Pereonite 5without dorsal spines. Pereopod 5merus without posteroproximal shoulder. Pereopod 6basis with posteroventral lobe weakly produced; merus longer than broad, without posteroproximal shoulder. Pereopod 7basis subrectangular with posterior margin smooth; merus length of anterior margin 1.7 × proximal breadth. Epimeron 3posterior margin without projections, posteroventral corner broadly rounded. Uropod 3biramous, inner ramus extending more than halfway along outer ramus but not reaching base of article 2. Telsonas long as broad, entire.
Remarks. Pachychelium fucaensisand P. davidisboth have four setal-teeth in either a 4/0 or 3/1 arrangement. However, P. fucaensishas the dactylus of gnathopod 1 over-reaching the palm (just reaching corner of palm in P. davidis). Pachychelium fucaensisis the only species with a produced corner on the palm of gnathopod 1.
Distribution.Vancouver Island, British Columbiaand southern California, eastern North Pacific Ocean; 85– 222 mdepth.
1976-08-28
NMCC
G. W. O'Connell
Canada
Vancouver Island
85
48.383614
Clover Point
18
-123.36278
Juan de Fuca Strait
31
32
NMCC 1988-0047
1
British Columbia
holotype
RV
Thomas G. Thompson
United States of America
Bureau of Land Management Survey
105
33.816666
Santa Rosa Island
119
-119.99834
Santa Cruz Basin
31
32
LACM 77, 283.2
1
California
paratype
RV
Thomas G. Thompson
United States of America
Bureau of Land Management Survey
247
33.77
Santa Cruz Island
119
-119.848335
Santa Cruz Basin
31
32
LACM 77, 284.1
1
California
paratype
Canada
Vancouver Island
85
48.383614
Clover Point
18
-123.36278
Juan de Fuca Strait
31
32
1
British Columbia
holotype