SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '17ac2d2088d310a7b639ccf22d5a764ccbd8d06e5ee60b8b6a8672ebb06658d7' 
  AND token = 'RB5zPzf8z1Uh4T3FxDCloiV5A042RZRvAnBbBca7rTs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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