SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'afb3827f69b7c08008ab07c6ed45ba68ea96a458447df11c2825eff7c8f7c6a4' 
  AND token = 'FERM9Ol8RcaEHGqIHjZSw3HHv5OJRRKvS0NPTsWPsjs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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