What is "Sukos Benos"?
Rashi (from Sanhedrin 63b): It is the form of a hen 1 with its chicks.
Radak: This is like a rooster is called Sechvi. Alei Tamar (Yerushalmi Avodah Zarah 3:2) - it should protect them like a hen protects its chicks with its wings.
What are "Nargel" and "Asima"?
Rashi (from Sanhedrin 63b): They are the forms of (a) a rooster, and (b) a male goat, respectively.
Radak: Nargel is a wild rooster.
Radak, from Yerushalmi Avodah Zarah 3:2: They are the forms of (a) a foot, like Ragle of Yakov and Yosef 1 , (b) Imra 2 , like "Eil ha'Asham" (Vayikra 5:16), respectively.
Pnei Moshe (3:2): Yakov said "va'Yvarech Hashem Oscha l'Ragli", and it says "va'Yvarech Hashem Es Beis ha'Mitzri Biglal Yosef" (Bereishis 30:30, 39:5).
Imra is the Targum of lamb, but the Yerushalmi uses it to mean ram. (PF) Ramban (Vayikra 5:14) - Asham shields from Ashmah (guilt). Based on Kabalah, "Asham" is a male sin-offering.
Here it says that Bavel's idolatry was "Sukos Benos." Elsewhere it is called Bel - "Kara Bel Kores Nevo" (Yeshayah 46:1)!
Radak: It was Bel in the days of Nebuchadnetzar. In the days of Sancheriv, it was Sukos Benos.