SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '1aa5c938dfffb2f4efa5392e98825ad75ca4663487209fdf22e4af178b41ffec' 
  AND token = 'eO3fxeZ8h5KR7Hc8x9BcrOAJsZGdp/iMMKaxLEPJdq8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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