SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0cc58ac5c8be70ed8b939c74af5c3754fedef78479296ed45c57a1157bbb618a' 
  AND token = '4rQjlPXAZllCFqd+m9E1JzwLKJGMijkBnz2RDE9FnHs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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