SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '1aee86e307866be2fce1b383a55d752ba8dc3565a664df920f5263735e3919ac' 
  AND token = 'zDcrWhMIQTu4iLBgMTpjLZ1FUvndYLrxMJkSD0DRsVo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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