SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'f5d7293a21a238399814429a42e2ed48f66f414a30c21e750f38bff2c3548737' 
  AND token = 'nlE6ODcAB63uE417uVRNRP55xgNkZICrJpWBrnDs1O8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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