Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '823b0e2f6bd159ee51228a972ddfcf4ffb5a98c5ec1d34f140665a555579a7b2' 
  AND token = 'fEnyNVFaTNeo/9+pHrgg3emkvUiARMFCWuDYa78PCh0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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