SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2233dbaea7fd84b48f188e9e4bbfbcf9fe5a50ffa5fa59e2a5cd947759b081dd' 
  AND token = 'sj7zGyStn0GwkR41exD+bSh8luuPZBnaINJB4vyAkQI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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