SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5d2fe329e1d7eb1772e3a0d2c173f44caac3a43ce531d55e85e8775978318e25' 
  AND token = '3GCYDt0XBPw7c6+3vIr84fv9KlzuJVIT0kTfDDr57nk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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