SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '02f2aff4654ff42ff6e92648da5db581b928d70e43b89f1d15a9170440983f21' 
  AND token = 'YUnEHZ65N/UTM4rqaX9qCEOSzBv7mPSjysPOdJ/hdcs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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