Recent arrival of Nemo and crew at sea (8)
I believe the answer is:
newcomer
'recent arrival' is the definition.
(I've seen this before)
'nemo and crew at sea' is the wordplay.
'and' means one lot of letters go next to another.
'at sea' is an anagram indicator.
'nemo'+'crew'='nemocrew'
'nemocrew' anagrammed gives 'NEWCOMER'.
'of' is the link.
(Other definitions for newcomer that I've seen before include "He has just arrived or started" , "Late arrival" , "Starter" , "2 arrival" , "Recent arrival" .)