SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2adea3f96483a779bd8d300f69cc827d9b16fffedc3f9143abeca024b8bcfd57' 
  AND token = 'WPT/ZOTgyMz9ZwCM2pHKDDUJG5gbYSh8G8mAjHbLicg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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