SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '85b08e499b4ef2d7c45287e9680323cfe15658edaabf6bdb792063c334936cc0' 
  AND token = 'KgtYBkB4nHWWnHZHoeTY1vASAgK1L9A04lkf4qAFfIo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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