SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '80787d2f5fabc19492749b299b86c352fca08595c61a47af3fde055f4e775ec4' 
  AND token = 'HkiPqJ7qX9+gjzNComPNKhdiaGZDTXeV4N3jRsqBi9w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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