SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9e60a995fa872c84e209667451d366e33ca44ce78c4b76a6e89de7508e429e7f' 
  AND token = 'oaGBJz8ingjcvwx+QFnRaGuTIZ6A1Sy/+PhgOmCqQFU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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