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Appendix
A Key to the field characters of the gobies of the Upper Blackwater
Estuary (see also Figure 3).
1. The body is not transparent........2
The body is transparent..........Aphia minuta
2. The body has many spots or no spots on each
flank................3
The body has only two prominent spots on
each flank................Chaparrudo flavescens
3. There is a 'long' caudal peduncle and many
spots on each flank............4
There is a 'short' caudal peduncle and no
spots on each flank............5
4. The fish has two bars going forward and
down from the eye and has many spots on
each flank............ Pomatoschistus microps
The fish has one bar beneath the eye and has 4
or 5 spots on each flank, that at the base of
the tail being most prominent ......Pomatoschistus minutus
5. The 1st dorsal fin has a dark spot at the back
of the base of the fin and another on the
upper leading-edge............Gobius niger
The 1st dorsal fin has a yellow band along
the upper edge..............Gobius paganellus