SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a9dcf8a9138db352ddba203287b7fdd8071c3b76f2a1b92eaea6a24ed11064ae' 
  AND token = 'i6lLz7lUYSaZO2PI+07oSfk/hlpLSp/jC9aIuGYAw8k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}