SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9c54ccd1d8b402a0ca00c92193d28b9da464eb7f217b203eb1a3e140f0a2773f' 
  AND token = 'MjL2MGhk0joSuJnj6/r4FhDGTB5GjK1W4Ix0tKc9MMg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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