Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5a8b5589189206d0811855e532eb3faaa277c08736fd0786db7fe2e1bcca4754' 
  AND token = '4k53IMfntYRFgGJxxZ8I7l7orXIC84DfiJyf9Lchyag=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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