SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fd4e0bde61091284d8cca3b1b3a1b15808e949a6284c6d49e234a7c4b9b14019' 
  AND token = 'xANTctehzzd+FsAF180GdgONqAZkSuZMFc3z8AHevrc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}