SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e165dd0d63172794f84b2b4bca75ea9a622b2a6ee931485e3227e2dfb83c837e' 
  AND token = 'gJ1AEalj09i7FLv9O+8zZ86q8FQRc+5ABs4kgPI8uOU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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