SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1df039ba5cc85b022fa91b5fdadc943f54afacf4f56fe764c9aa77a83d15d030' 
  AND token = 'vUoM4JCMuRs/zorl4+zCzMFy9ZmBWglXGqKvzpHlIGQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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