SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '492ffe84b6dd35b31dda14760c79dc4f88a6f29f9f7cd43abbb032e68e4b2695' 
  AND token = 'pcuEPkkBMI5H/BRG/lO+PPJoiOqrh3ZxYX+vn08OhXE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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