SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9374623da35b61db72dce2dedfc2c0fe12cfd9f689053edef42df891245d9b95' 
  AND token = 'YApL3grtSVfTXKsueufUod5hYslvpQkfA5pz6Ebm3O4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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