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Records of the Australian Museum (2009) Vol. 61 
Figure 6. SEM of Megalomma cf. acrophthalmos, MAGNT W14008. (A) dorsal collar margins with dorsal lappets; (B) lateral collar margins 
and anterior thoracic chaetigers, lateral view; (C) anterior collar margins and ventral lappets; ( D ) chaetae first thoracic chaetiger, ventral 
view; ( E) chaetae of second thoracic chaetiger, ventral view; (F) uncini, same segment; (G) uncini last thoracic segment; (H) companion 
chaetae posterior thoracic chaetiger; (/) chaetae, anterior abdominal segment; (7) uncini, same chaetiger. 
from Queensland (Figs 2J-M). The thorax is anteriorly 
pigmented, particularly dorsally and ventrally around tori. 
The base of the branchial crown is also pigmented, there is 
a longitudinal medial line basally on each radiole, and some 
specimens also exhibit irregular, variable-width, transverse 
bands of pigment on the crown. 
Etymology. The name of this species refers to the 
discontinuous arrangement of eyes on the radioles. 
Remarks. These specimens do not fit into the classification 
proposed by Knight-Jones (1997) as her categories do not 
consider the combination of the following features: dorsal 
margins of collar not fused to the faecal groove, pockets 
present and compound eyes in dorsalmost and also in some 
lateral radioles. These characters, common to all these 
specimens, justify the inclusion of a new category (called 
Group 2E herein) in Knight-Jones’ classification. The collar 
pockets could be considered as vestigial or even absent in 
some specimens and therefore this species should also be 
compared with those previously placed in the categories 
2B, 2C and 2D which also lack dorsolateral collar pockets. 
The new species resembles M. messapicum Giangrande & 
Licciano, 2008, from the Mediterranean, in the particular 
arrangement of compound subdistal radiolar eyes, with 
a large eye almost surrounding the tip of the dorsalmost 
radioles, as well as some lateral radioles bearing small, 
similarly-sized subdistal radiolar eyes, and with those 
radioles between the dorsalmost and lateral ones lacking 
eyes (see Table 1). These two species, confined to distant 
and isolated geographic areas, are distinguished by the 
difference in the degree of fusion of collar margins with 
the faecal groove, separated in M. interrupta n.sp. and 
fused in M. messapicum; moreover M. interrupta n.sp. is 
characterized by the presence of large interramal lobes in 
thoracic notopodia and a radiolar skeleton with around 10 
cells in transverse section, whereas M. messapicum does 
not possess enlarged interramal notopodial lobes, and has a 
radiolar skeleton of four cells in cross-section (Giangrande, 
pers. comm.). 
Megalomma cf. miyukiae Nishi, 1998 
Figs 5C, 10 
Megalomma miyukiae Nishi, 1998: 53-59, figs 1-4. 
Material examined. Northern Territory. MAGNT W331 (1 spec.). 
Coral Bay, Port Essington, 11°1T50"S 132 o 02'55"E, collected by D. 
Staples, 17 May 1983, broken reef, 3-5 m; MAGNT W17354 (1 anterior 
