SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4dcd6e39322e0c9cb257a2be91abb6e612a41c1cf083448c6856342d5742d350' 
  AND token = 'bt3eIPjJmVRJU/nXBiYRnxVfZvSh8YTUW2okIFq/LtU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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