SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '4cd9413bfaba324c05bec9c1d63e0e0fd20e227e124650270956717bb5a8a2fa' 
  AND token = 'uVVn+PfqqmqHeFu0cNyWX9RZK8z4iuhc8RAtVRA/OYs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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