Hughes: southern Australian podocerid amphipods 
81 
Figure 8. Podocerus akanthius sp. nov., paratype female, AM P.86153,4.1 mm, Twofold Bay, New South Wales (scales represent 0.1 mm). 
margin with 1 short and 2 long robust setae; propodus 
subovate, palm smooth, defined by 2 robust setae without 
palm defining corner. 
Description. Based on holotype male, 4.4 mm, AM P.86150. 
Body cuticle dorsally processiferous, with mainly posterior 
dorsal carina, without lateral and ventral carina. Head 
dorsally smooth; eyes greatly bulging; lateral cephalic lobe 
subquadrate; anteroventral corner subquadrate. Mandible 
accessory setal row with 3 setae. Maxilla 1 palp distal margin 
with 4 robust setae. Pereonites 1-6 without dorsal carina. 
Coxae 1-3 discontiguous, coxae 4-7 contiguous. Gnathopod 
1 coxa subequal to coxa 2, broader than long, distoventral 
comer elongate produced ventrally; basis 2.5 times as long 
as broad, with a few slender anterodistal setae; carpus 
rectolinear, twice as long as broad; propodus subrectangular, 
2.2 times as long as broad, anterior margin with sparse 
slender setae, palm margin minutely serrate, with 4 robust 
setae near corner of palm; dactylus posterior margin with 2 
serrate teeth, cuticle surface with raised serrations, closing 
along palm. Gnathopod 2 basis twice as long as broad, 
anterodistal corner produced into rounded lobes, with short 
robust setae; mems posterior margin with broad produced 
lobe, 1.1 times as broad as long, apically rounded, without 
short robust setae; propodus elongate, subovoid, 2.1 times as 
long as broad, anterior margin with clusters of short slender 
setae, propodus palm acute, straight, smooth, 3 A length of 
propodus, without distal shelf, palm defined by corner with 3 
robust setae; dactylus closing along palm. Pereonite 7 dorsal 
carina produced posteriorly, subtriangular, apically acute. 
Pleonite 1 dorsal carina produced posteriorly, subtriangular, 
apically acute; epimeron 1 posteroventral corner rounded. 
Pleonite 2 dorsal carina produced posteriorly, subtriangular, 
apically acute; epimeron 2 posteroventral corner rounded. 
Epimeron 3 posteroventral corner subquadrate. Urosome 
with 3 pairs of uropods. Urosomite 1 twice as long as broad. 
Uropod 1 peduncle elongate, 3 times as long as broad, with 
well developed ventromedial spine 3 times as long as broad; 
inner ramus 1.3 times peduncle length, outer ramus about % 
length of inner ramus. Uropod 2 well developed, biramus, 
without ventromedial spine; outer ramus about half the length 
of inner ramus. Uropod 3 uniramus; rami with apical setae. 
Telson dorsal lobe with 2 apical setae; lower margin with pair 
of long slender lateral setae, without apical setae. 
Female (sexually dimorphic characters) based on paratype 
1 female, 4.1 mm, AM P.86151. Gnathopod 1 basis anterior 
margin with 2 robust setae; carpus rectolinear, twice as 
long as broad; propodus subovate, twice as long as broad, 
palm convex, margin minutely serrate, defined by 2 robust 
setae, without palm defining corner; dactylus posterior 
margin with 5 serrate teeth. Gnathopod 2 basis anterior 
margin subquadrate, with several robust setae; merus lobe 
as broad as long, posterior margin with 1 short and 2 long 
robust setae; propodus subovate, 1.9 times as long as broad, 
anterior margin with a few long slender setae, palm convex, 
smooth, about half length of propodus, defined by 2 robust 
setae without palm defining corner. 
Remarks. The three posterior dorsal carina (pereonite 7, 
pleonites 1-2), with acute apices distinguish P. akanthius sp. 
nov. from other Podocerus species. Podocerus akanthius sp. 
nov. is similar to P. fulanus Barnard, 1962 from California 
which has four acute dorsal carinae. The male gnathopod 
2 propodus palm without a distal shelf defines Podocerus 
akanthius sp. nov., and three other Indo-Pacific species, P. 
brasiliensis (Dana, 1853), P. walked Rabindranath, 1972 and 
P walked pedonculata Ledoyer, 1979. Podocerus akanthius 
sp. nov. has the male gnathopod 2 propodus palm lined with 
sparse plumose setae, separating in from P.walkeri and P. 
walked pedonculata which has short robust setae along the 
palm, while in P. brasiliensis the palm has a thick brush of 
plumose setae. 
