SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2a2bd411dd07ab7b20d64853884b7fdd9e6905a190b468b64abedc985804e5d3' 
  AND token = 'p5Eecojw3K8TZmMM39N06/xfZyxzEpEwbZr6eIEaWMs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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