Sandbox

SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '400e8e1895d5d43848c97f281ece608cc8bd21f35d0dec92fada72f721cfba9a' 
  AND token = '0iKWl5P5EJW2bW6JPET8YOJvY1aCqS2KpZV0OzO5FSE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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