SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '19ef08a6d2908ed842c63ba4bcb4d265c76a0eb667f0f266c360e6c6a2c0746f' 
  AND token = 'wGT+rK1iO5wpbRUXHB7+aAw5JsQSEsRXXmtHyfrhvgQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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