SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f88a891321511d6d81ec469c2a84395b0612d70726b7945b020abad92a2fd148' 
  AND token = '6mWK9sYFx/h9Y0paUOpzM8CSdToTg4qBtXN0jqxpKw4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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