SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ed900f647bbfb2e202db0e438a72d6da9d946d7f10f5caf7c4e0ba9902539674' 
  AND token = 'DxGoMXu9hi6YpD7ZisJnq8wCzw1n2YTHtA+VowYJMjg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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