SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ed14aeb04b1d4fc95fbfb7c33ea3fad3f53243bb543ec7522e2b8105f7a3c769' 
  AND token = 'ruWQnLWNI2NXPyLxVrA8emsP/7Rpp49W29NzRK379CU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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