SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f13bfddc3ea0be9a14d170dd6d145f752bbb9d09d54cf11dc1ab6f3efd8a76bd' 
  AND token = 'MIcI0bWSqnPUCXpPZdO752fjnMuW8IBSwwUDCasttfA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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