SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bba3c0d279a847c9734c84af080677b21b207e322e077e67960f7152e0a3139e' 
  AND token = 'WGr0OwpdOFWziLM7ODIYKV+W/zo0xFzifmKDwCaABqE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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