SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'd7e40f52f7a0f9216513c536e34005d63eb693afaf4a619570d5b31ba935bf4a' 
  AND token = 'uQ2aAenPCkd52TGC8j357/ZZkqfIq4Gr616ymrjTt+U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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