SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '13352915a758f6cfc63d11deb828aafcda60034553301680ac1b9c3cef896d4d' 
  AND token = 'Yz/PrvDRdP2Vu4IwZqAo+hcAvNe/+yj9qRjgHka9PH0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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