SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '06bc09f5ce0600795d72a6edcd34384970a892df28de738a93f094f737998216' 
  AND token = 'fxHP1PklVnbU9L5uDuQc5Yyj+hvM9xDZy5xqAZagaPU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}