SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ccc57e03a4fe4c24b573fbd6506a2a6c59a8b41f93c6f4d4497be0b5cc4f9498' 
  AND token = 'vhpIg/RMKCEHGv81UjTDmaXg0dgxBGFn/LnOzAioPYU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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