SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6302c61eb6bc43fd09a1d70d7d8e191fc48f643c0a873b85c1a0587152e2750d' 
  AND token = 'bW76Ea65GD0a0B9g0untsPtWrTHnCFADIgBkajMYcTw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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