SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '472cf8c9dc0669c3567355a923f533c61427c059014d15d61bfc89e5e1acafb5' 
  AND token = 'skFxkHMVPOSY+FNxRYcyv8ookgZWpJe1cVNOWKOEfzM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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