SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9cbfb980fe7560db41167147cb138ea4a4de8a425f1b5c179ce3818c159248fe' 
  AND token = 'HT4aJt3pV+fdvb4FBVhWXWLpeZWYgYHtngBJKKkOJqU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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