SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5484603bcdb9551af5f50f40db7b916d8886abdc3712cc9cf1e1cb99a0132d54' 
  AND token = 'wRgH6SgualvoZ9rIdciDeTng+2O2yBq3yZTwUMjHw7w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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