SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'f44edb9b998cf2b07f3e90c15b7771b2b0f47633128230ddb1c700e4240ac651' 
  AND token = '5jAFWsuYmYxIWMAQ17ntY0uLeQFYwoQov5gpqN7KZiw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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