SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '45b4c0df694b69d6f605ed04aaa8188dbda4485b5fd73ef101f3534e11fe9a7d' 
  AND token = 'b1PDphobP4NWDduSvJiHhm7CcfcvC+p9SbEeNUVKUFk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00064

JSON explain

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