SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9f05e9d073761a5cd4fd624a277718d795da3b313ac71784f1416f7d22af7d47' 
  AND token = 'f4bGEIXctW8RWGg5zvi3WeCsqdHQqbsknTGV683ekWA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00070

JSON explain

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