SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'db9ddd6eebfe2f893007f5c40d867fec316524178174151d4335bea8188dd3a3' 
  AND token = 'JQVZCHbDc+Rry5COC3g9ORT1qoS7+boSN7hZucrq93M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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