SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c33476393b8c107e6351b96124179e2a67cae9a97e45aa3e1a5718a25f0ca359' 
  AND token = 'aGsv/iNyB/KnqK58crKVHz/UnjYafb9Gw8gcA7r+XjY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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