SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9a5b06e7d1c63d2f115b929bfb5a6dac33fcc98d1d76813f3d9e7247edae7ce5' 
  AND token = '6GdLkZuGePC7Vj+09OZJzusR/sJjoHfexKKOxUk4cDw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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