Martin et al:. Smenispa, isopod parasite of Australian fishes 
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Bruce (1987) placed the genus within the Anilocrinae 
(mostly external attaching genera) on the basis of cephalon, 
brood pouch and pleopod morphology, Bruce (1990) later 
suggested avoiding the name Anilocrinae as position on the 
host and associated body shape was not a reliable indicator 
of phylogenetic relationships between genera. Ketmaier’s 
et al. (2008) molecular dataset (based on a small number 
of species, inevitably had strange pairings) provide strong 
support to Bruce’s (1990) warnings. In particular, we do not 
support the hypothesis of a “linear” evolutionary pathway 
that starts with externally attaching forms (Anilocrinae) 
and ends up with gill-mouth dwellers (Livonecinae + 
Cymothoinae) as previously suggested by Brusca (1981). 
Smenispa irregularis (Bleeker, 1857) 
Figs 1-5 
Cymothoa irregularis Bleeker, 1857: 34, pi. 2, figs. II.— 
Miers, 1880: 462.—Gerstaecker, 1882: 261. 
Cymothoaparadoxa Haller, 1880: 378, pi. 18, figs. 5-7.— 
Gerstaecker, 1882: 261. 
Enispa irregularis. —Schioedte & Meinert, 1884: 293, pi. 
11, figs. 1-4.—Nierstrasz, 1915: 95.—Nierstrasz, 1931: 
137.—Trilles, 1979:259, pi. l,figs. 6; 1994: 152.—Bmce, 
1990: 282, figs. 24-25. 
Type material. Syntypes 2 9 (ovigerous 19 mm, 23 mm), 
Rijksmuseum van Natuurlijke Historie (RMNH 62), “Oost 
Indie”, coll. P. Bleeker (not examined). 
Material examined. Western Australia: 1 $ (24 mm, ovig., 
damaged pleonite, mouthpart and pereopods), 1 S (9 mm), 
AMP89833, from Carnarvon, 24°53'S 113°40'E, 1982, from 
buccal cavity of yellowfin seabream Acanthopagrus latus 
(Houttuyn, 1782). 
Diagnosis. Female. Cephalon embedded in pereonite 1. 
Pereonite 1 anterior margin trilobed; lateral margins of 
pereonites subparallel, pereonites 1 and 2 arching anteriorly, 
pereonite 2 posterolateral margins produced, lateral margins 
of pleonites subparallel and arching posteriorly, pleotelson 
subtruncate and endopod larger than exopod. Male. Body 
similar to female; cephalon dorsally visible; pleon width 
0.6 pereonite greatest width; pleopod 2 appendix masculina 
slender, apex distally acute, length 0.8 endopod length, not 
reaching beyond exopod; pleopod 2 endopod length 1.9 
width, medial margin produced, slightly extending exopod; 
exopod length 1.5 width, proximal lateral margin strongly 
produced. 
Description. Female. Body length 2.0 greatest width, dorsal 
surface smooth appearance, widest at pereonite 5, most 
narrow at pereonite 1. Cephalon length 1.0 width, visible 
from dorsal view, embedded in pereonite 1; frontal margin 
ventrally folded. Eyes indistinct, eye width 0.1 width of 
cephalon. Antennula shorter than antenna, comprised of 8 
articles; article 2 length 2.0 article 1 length; not extending to 
posterior margin of eye. Antenna comprised of 12 articles, 
last article terminating without setae. 
Pereonite margins smooth, increasing in width from 
pereonites 1-5, pereonite 1 length 0.3 width, anterolateral 
margin produced, extending past cephalon; pereonite 5 
widest, length 0.2 width; pereonite 6 and 7 lateral parts 
with posteriorly produced lobes. Coxae 2-3 posteroventral 
angles produced; 4-7 not acute posteriorly, with oblique 
carina. Pleonites visible in dorsal view; lateral margins 
arching posteriorly. Pleonite 1 posterolateral angles not 
hidden behind pleonite 2; pleonites 1-5 subparallel. 
Pleotelson length 0.5 anterior width, dorsal surface smooth, 
anterolateral margins weakly convex, posterior margin 
straight, without median point. 
Pereopods 1-7 dactylus narrowly curved, merus and 
carpus of similar length, not produced. Pereopod 1 basis 
length 1.8 greatest width; ischium length 0.6 basis length; 
merus proximal margin without bulbous protrusion; 
carpus with straight proximal margin; propodus length 1.3 
width. Pereopods 2 and 3 similar to pereopod 1, gradually 
increasing in size. Pereopod 6 basis length 2.0 greatest width, 
ischium length 0.4 basis length. Pereopod 7 basis length 1.6 
greatest width; ischium length 0.6 basis length, merus length 
0.4 ischium length, merus length 0.7 width; carpus length 
0.1 ischium length, carpus length 0.3 width. 
Pleopods (damaged), without setae. Uropod half the 
length of pleotelson, protopod length 0.8 endopod, protopod 
lateral margin without setae; rami not extending beyond 
pleotelson, apices bluntly rounded. Endopod apically not 
bifid, length 3.0 greatest width, lateral margin proximally 
convex, distally concave. Exopod shorter than endopod, 
length 2.8 greatest width, apically not bifid, terminates 
without setae. 
Male. Body subparallel, length 2.2 width. Cephalon length 
1.5 width, visible from dorsal view, not embedded in 
pereonite 1. Eyes distinct and well developed. Pereonites 
without posterior lateral lobes, similar in length. Antennula 
comprised of 8 articles. Antenna comprised of 10 articles, last 
article terminating without setae, extending to posterior of 
pereonite 1. Anterior margin of cephalon subtruncate, without 
small median point. Mandibular process present, covered in 
pectinate scales, article 3 with fine setae. Maxillula with 3 
narrow spines. Maxilla mesial lobe with 2 recurved spines, 
partly fused to lateral lobe with 2 recurved spines. Maxilliped 
article 3 with 2 recurved robust setae. Lateral ends of pleonites 
less developed than in female. Pereopods 1-7 similar to 
female; dactylus length 0.8 basis length. 
Pleopods without setae, without lobes on pleopods 1-2. 
Pleopod 1 exopod length 1.3 width, lateral margin weakly 
convex, mesial margin weakly produced; endopod length 1.7 
width, lateral margin straight, mesial margin slightly convex; 
protopod width 4.0 length. Pleopod 2 endopod length 1.9 
width, medial margin produced, slightly extending exopod; 
exopod length 1.5 width, proximal lateral margin strongly 
produced; appendix masculina slender, apex distally acute, 
length 0.8 endopod length, not reaching beyond exopod. 
Pleopods 2-5 with basal projections; exopods proximal 
lateral border extending beyond protopod; endopods 
proximal mesial boarder extending past protopod boarder, 
endopod dorsal with large medial fleshy folds. Uropods 
dorsally visible, slightly hidden by pleotelson. 
Colour. Present specimens (female and male) dark orange 
brown. Bruce (1990) reported pale tan in the Northern 
Territory specimen with no chromatophores present. 
Size. Non-ovigerous female 24 mm, male 9 mm. Other reports 
include Bleeker (1857) (female: 28 mm), Schioedte & Meinert 
