SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c2edadba6e2bf96fdee464d0a0d993e6f3487f661bc5ebb011cf232757fa5dee' 
  AND token = '/nNpfEIwJsHj/TEX586tXxpVI+ekE12HXvFXKRMRPhU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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