SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8a9db0288ea171bb46c2e622f5ba7d245b5b6494d56c2cc35a4e52b07a480770' 
  AND token = 'rkuOIh3sxQx+UuRxz/ptyHQNph0KYdWXKUQmfLRR6d0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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