Exampithoe burrowwo, Hughes, Lauren E. & Peart, Rachael A., 2015

Hughes, Lauren E. & Peart, Rachael A., 2015, Three new species of Exampithoe from Australia and New Zealand (Ampithoidae: Amphipoda: Crustacea), Zootaxa 3918 (4), pp. 559-570 : 560-563

Exampithoe burrowwo sp. nov.

( Figs. 1–3 )

Type material. Holotype: male, 10.5 mm, dissected, 4 slides, AM P.92555, Shark Bay, Port Jackson, New South Wales, Australia (33°51'12"S 151°15'54"E), subtidal, macroalgae, coll. A.G.B. Poore, 2012. Paratypes: 7 males, 2 females, AM P.88413, same location as holotype.

Type locality. Shark Bay, Port Jackson, New South Wales, Australia.

Etymology. From the Australian indigenous word, burrowwo , meaning shark, applied as a noun in apposition.

Diagnosis. Mandible accessory setal row with 4 robust setae; palp 2-articulate; article 1 subequal in length to article 2; article 2 apically setose. Labium outer plates weakly excavate to entire, without an apical duct; mandibular lobes with curved margins, rounded apically. Maxilla 1 palp article 2, with apical slender setae, without apical robust setae. Maxilliped outer plate with developed row of large robust setae along medial margin. Coxae 1–4 as long as broad. Gnathopod 1 subequal in size to gnathopod 2; coxa distinctly larger than coxa 2, as broad as deep, anteroventral corner produced, anterior margin straight, anteroventral corner acute; basis longer than coxa, anterodistal lobe large and rounded, with 6 slender setae; ischium anterior margin without lobe; merus anterodistal lobe subacute, posterodistal corner rounded; carpus elongate, rectilinear, twice as long as broad, longer than merus, longer than propodus, anterior margin with slender setae; propodus narrow, subrectangular, length twice width, palm extremely acute, convex, without posterodistal shelf, posterodistal corner rounded, with 1 robust seta defining palm. Gnathopod 2 basis longer than coxa, anterodistal lobe large and rounded, anterodistal corner with 3 slender setae; ischium anterior margin without lobe; carpus subrectangular, longer than propodus, anterior margin with slender setae; propodus subrectangular, narrow, palm acute, convex, posterodistal corner rounded, with 1 robust seta defining palm. Epimera 1–3 posteroventral corner broadly rounded. Uropod 2 inner ramus with 4 lateral robust setae; outer ramus with 2 lateral robust setae.

Description of holotype. Head as long as deep. Antenna 1 unknown. Antenna 2 robust, stout; peduncle article 4 subequal in length to article 5; flagellum longer than peduncular article 5, with 21 articles. Labrum directed nearly straight down, lateral margins without midlateral notches. Mandible molar well developed, triturating, accessory setal row with 4 robust setae; palp 2-articulate; article 1 subequal in length to article 2, length 4 times width; article 2 with 2 apical setae. Labium outer plates weakly excavate to entire, without an apical duct; mandibular lobes with curved margins, rounded apically. Maxilla 1 inner plate, unknown; palp article 2, with apical slender setae, without apical robust setae. Maxilla 2 inner and outer plates subequal in width; inner plate without oblique setal row. Maxilliped outer plate with developed row of large robust setae along medial margin.

Pereon. Coxae 1–4 as long as broad. Gnathopod 1 subequal in size to gnathopod 2; coxa distinctly larger than coxa 2, as broad as deep, anteroventral corner produced, anterior margin straight, anteroventral corner acute; basis longer than coxa, length 3.8 times width, anterodistal lobe large and rounded, with 6 slender setae; ischium anterior margin without lobe; merus anterodistal lobe subacute, posterodistal corner rounded; carpus elongate, rectilinear, twice as long as broad, longer than merus, longer than propodus, length 1.2 times propodus, carpus lobe absent, anterior margin with slender setae; propodus narrow, subrectangular, length twice width, palm extremely acute, convex, without posterodistal shelf, posterodistal corner rounded, with 1 robust seta defining palm; dactylus subequal in length to palm, inner margin serrate. Gnathopod 2 basis longer than coxa, length 3.6 times width, anterodistal lobe large and rounded, not reaching beyond ischium, anterodistal corner with 3 slender setae; ischium anterior margin without lobe; merus posterior margin without lobe; carpus subrectangular, length 1.3 times width, longer than propodus, anterior margin with slender setae; propodus subrectangular, narrow, length 3 times width, palm acute, convex, posterodistal corner rounded, with 1 robust seta defining palm; dactylus subequal in length to palm, tapering evenly, apically acute, inner margin serrate.

Pleon. Epimera 1– 3 posteroventral corner broadly rounded. Uropod 1 unknown. Uropod 2 peduncle without distolateral projection, margins with 6 robust setae, slender setae fringe absent; inner ramus longer than outer ramus, with 4 lateral and 2 apical robust setae, slender setae absent; outer ramus with 2 lateral and 2 apical robust setae, slender setae absent. Uropod 3 peduncle much longer than broad, length twice breadth, 4 times rami length, without marginal or apical robust setae, with marginal and distal slender setae; rami short, as long as broad; outer ramus subequal in length to inner ramus, with 2 large recurved distal robust setae, without patch of small lateral denticles or lateral setal fringe; outer ramus with 1 apical robust setae and distal slender setae. Telson subtrapezoidal, apically rounded, with small apical cusps, with 3 pair of lateral setae and 2 pair of lateral plumose setae.

Remarks. Exampithoe burrowwo sp. nov. is similar to E. gracilipes in that the mandibular palp is reduced with only 2 articles. Exampithoe burrowwo sp. nov. can be distinguished from E. gracilipes by the gnathopod 1 coxa where the anterodistal corner is subacute, and the basis anterodistal corner has a large rounded lobe, while in E. gracilipes , the coxa is rounded and the basis lobe is weakly developed and subquadrate.

Distribution. Australia: Port Jackson (current study).

Figures

FIGURE 1. Exampithoe burrowwo sp. nov., holotype male, 10.5 mm, AM P. 92555, Shark Bay, Port Jackson, New South Wales, Australia.

FIGURE 2. Exampithoe burrowwo sp. nov., holotype male, 10.5 mm, AM P. 92555, Shark Bay, Port Jackson, New South Wales, Australia (scales 0.1 mm).

FIGURE 3. Exampithoe burrowwo sp. nov., holotype male, 10.5 mm, AM P. 92555, Shark Bay, Port Jackson, New South Wales, Australia (scales 0.1 mm).