The Marine Fauna of New Zealand: Isopoda, Aegidae (Crustacea)

the subgenera and could not apply the subgeneric
concepts (e.g. Bruce 988, 996, 2004a; Kensley & Chan
200 ). Notwithstanding, Brusca had recognised an
evident division within the genus, one that the present
analysis supports and validates, albeit using different
and rather more character states.
Brusca ( 983) was apparently unaware of some
of the several older and available names that were in
synonymy with Aega. Aega plebeia, the type species of
Rhamphion falls within the genus concept and within
the major clade that contains Aegiochus, so that name
takes priority.
Thirty-seven named species are included in the
genus, those below, and those listed under ‘Species
included ...’ (p.2 3).
Key to the new Zealand species of Aegiochus
Eyes large, medially united ..................................4
– Eyes separate ..........................................................2
2. Pleotelson entire .....................................................4
– Pleotelson with quadrate median excision ........3
3. Pereopod dactylus .4 times as long as propodus;
coxae 5–7 dorsally weakly concave, posteriorly
produced and acute ...................................
................................................Aegiochus beri (p. 85)
– Pereopod dactylus .0 times as long as propodus;
coxae 5–7 dorsally convex, posteriorly
weakly rounded ..............Aegiochus riwha (p. 4 )
4. Rostrum folded ventrally and posteriorly, appearing
truncate in dorsal view; in contact with or
overlapping anterior margin of frontal lamina ...
..................................................................................7
– Rostrum ventral or ventrally directed, not folded
posteriorly, appearing subtruncate or absent in
dorsal view, not overlapping anterior margin of
frontal lamina .........................................................5
5. Frontal lamina ventrally flat, pentagonal (‘cirolanid-like’);
adult males with rostrum extended
to form prominent process and pereonite with
paired sub-lateral processes giving tri-horned appearance;
eyes huge, largely occupying anterior
margin of head ............Aegiochus vigilans (p. 50)
– Frontal lamina short, with posterior stem, not
ventrally flat; males and females without processes
on head or pereonite ; eyes narrowly joined
medially ...................................................................6
6. Eye join medially narrowly (2 or 3 ommatidia);
pereopods 2 and 3 carpus inferior margin distinctly
lobed with prominent RS; average size
approx. 4 mm .............Aegiochus bertrandi (p. 88)
– Eye join moderately wide (3–5 ommatidia); pereopods
2 and 3 carpus inferior margin not lobed,
with only small RS; average size approx. mm
............................................. Aegiochus coroo (p. 93)
84
7. Eyes separate ..........................................................9
– Eyes medially united .............................................8
8. Eyes moderate in size, occupying less than 40%
head length; frontal lamina posterior margin
concave; posteroventral angles of pereonite
and coxae 2 and 3 acute, each with posteroventral
point; appendix masculina straight. ......................
............................................Aegiochus kakai (p. 09)
– Eyes large in size, occupying more than 60% head
length; frontal lamina posterior margin straight;
posteroventral angles of pereonite and coxae 2
and 3 truncate, each without posteroventral point;
appendix masculina sinuate ...................................
......................................... Aegiochus kanohi (p. 4)
9. Frontal lamina with distinct posterior blade;
pereopod dactylus as long as or longer than
propodus ............................................................... 0
– Frontal lamina without distinct posterior blade;
pereopod dactylus slightly shorter (0.9) than
propodus .................... Aegiochus insomnis (p. 03)
0. Pereopods –3 without distinct, triangular distal
blade .......................................................................
– Pereopods –3 with distinct, triangular distal
blade ...............................Aegiochus piihuka (p. 28)
. Pleotelson without RS ......................................... 2
– Pleotelson with 2 or more RS ............................. 3
2. Adult size ‘small’ (average 7.7 mm males, about
2.4 mm females); eyes separated by 7% head
width; uropod endopod mesial margin usually
with 3 RS; dactylus .4 times as long as propodus
.............................. Aegiochus gordoni (p. 97)
– Adult size ‘tiny’ (average 5.4 mm males, about 8.0
mm females); eyes separated by 6% head width;
uropod endopod mesial margin with or 2 RS;
dactylus .2 times as long as propodus ................
......................................Aegiochus nohinohi (p. 23)
3. Eyes large, separated by less than 5% head width;
pleotelson with 0 or more RS .......................... 4
– Eyes small, separated by 32% head width; pleotelson
with 2 RS ...............Aegiochus laevis (p. 20)
4. Eyes separated by 2% head width; anterior
pereopods stout, propodus .7 times as long as
wide; coxae not conspicuous in dorsal view, not
posteriorly produced ...............................................
......................................Aegiochus pushkini (p. 34)
– Eyes separated by 4% head width; anterior
pereopods slender, propodus 2.9 times as long as
wide; coxae conspicuous in dorsal view; coxae 6
and 7 posteriorly produced, acute .........................
............................................. Aegiochus tara (p. 46)