SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '65abe6469e4b0c28fcd5d37bbf2b5933d11705d2b326d0d898e87127892925c9' 
  AND token = 'E96Y7EjEjZx4er1/xzvAIN3mGnzwPqQL79+86oRlohk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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