SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'd906af661cd4987c3cdda9abaa56e32f1d5c74073d50d6a5fbce44f656df3cb9' 
  AND token = 'deyPSkWPetjKrXDyOMnRNR+m9/5xebovZQsXBK+T9SA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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