SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7b86ee8fea850ebfa11968a39e64610feda9b317a43843cb76f8b2e34e85302e' 
  AND token = 'iWV/ykfvVnn3j3b3WWn0zF1wj5ry1iOjXJWRU+3PLoE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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