SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'eb9666bed41e5b164642a68feda2e851cd8eebf6a0785c7401886b905eb22978' 
  AND token = 'iQxE7AaaBhX63S/509GxkV206RZeuDXUbCRGv/QEghU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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