SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a09adca63d08ffef6157204fc27964dc5a8b6e7c44c26017b366a5687233f1d8' 
  AND token = 'MmcRc+VaBgoY8PoUitgjSl8NIpWYihMrp4KFCg6r3Vk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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