SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '12d44581ad298a3b59ca5235088f4db63fd041d8917bba374be9f87265e83c15' 
  AND token = 'YumCV3KXts1Wjg5OS173/17p6X0qKrLVN/UvzZ75nwU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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