SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f01d83e75173b48f0da841fc20afa86327efd9d4246dab89242fc3e9a20f1054' 
  AND token = 'iiCtJgI7fOtryvboJwS6LPntmj+yyao60cIraCbQlpk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

Explain
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Impossible WHERE noticed after reading const tables