SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '77a07c75174fe8241ef47c070416715c0648633f1e1694b9bd91b049eb2fd982' 
  AND token = 'yXLrkR+kX7WoEU7V2v6PkUnkL6QB013wJrgcGW+S2nQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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