Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '20a427252173b9ea5b1cc10cf779d969a40d6d32d27ca22e2243eaadf0603a2a' 
  AND token = 'jT0B8xq/AwYkJunqZMWbSXrz3iEt/5v2CSZExseEUwA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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