Parasite from death row condemned by Royal Marines (10)

I believe the answer is:

threadworm

'parasite' is the definition.
(threadworm is a type of parasite)

'death row condemned by royal marines' is the wordplay.
'condemned' is an anagram indicator.
'by' means one lot of letters go next to another.
'royal marines' becomes 'RM' (abbreviation).
'death'+'row'='deathrow'
'deathrow' with letters rearranged gives 'threadwo'.
'threadwo'+'rm'='THREADWORM'

'from' is the link.

I've seen this clue in The Telegraph.

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