SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd17c9da2247c4f5b3ac653da55afd68f0124fbd027304a25d1761549bbfcaefd' 
  AND token = 'ng7jeFsXpzQtljWYAiZYVbGzO52wci2eyDKDlEBGShE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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