SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '08036516c834928906794ad4da3ef178500fb57394ee229312e3ce55e7db9561' 
  AND token = 'VDDDI0xdqPZHbd51KUBss2cxW/QVJUGoNO3vMsHQFuU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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