SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '652dcfc15ba538a40d5eed53a3ee1558aade247fc9f057f16b71fe79e141b077' 
  AND token = '7g5Onndjd2EwJPF8iXcJgpqmte69Bx8jYQGt70S3u9w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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