SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '566e1430635b299b567eb1ca48f87c154a2bbe12ffaf5171b257ed625542262f' 
  AND token = 'BbrZYPQ6fgxVDjQgyxttj9YB9Qbz7GnOzMaViCksYLE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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