SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4dea57eb3b51152dfe2b731a6a01927c011da5dda344237a8a7557eacb011461' 
  AND token = 'VANimrzVj05mGPZKGXOfawgYwHnzSODsbkTvjR+bDlk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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