SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c53252b75e62dfbabbce45dfff44da5d1409825942a48a9ac2c1fe08a749f2ab' 
  AND token = 'TnR5TX9Ic9VLg0kybkU915vGDo0QmVjodmp0jQ/0NRw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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