SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '8db67afaf7b58797930eabd73b63c3c2b56061d1d3043a00227c46e1d809a60f' 
  AND token = 'I1giXo2ZbW6J6VKp9VIzA9Xx2cTXcUkvODzAZuC3wNw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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