SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '898e61c6e598b050e67fe56d755e2487d02e86e2a144c976bd5a5c39ebb0725c' 
  AND token = 'xV4Oz/6fryAy0snXu/xhW4H7sYbo9x8AR4a8O2bFk8w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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