SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '93c8ee29384a7468656645b5fe2fa48300b671d353189698b2434221dfb0ba49' 
  AND token = 'RybE6Zp6H35dVvu/sPd/QwVf0mKFgKzllKOSxdn8HtE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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