of al-Dhahabi it appears as “Amr,” spelled with a waw. And Allah knows best.
I found another corroborating report with the wording: “Do not eat while bent over, and do not step over people’s necks on Friday.” Al-Tabarani narrated it in al-Awsat (52/1—its supplementary material), and Ibn Asakir narrated from him (13/196/2), through Abu al-Yaman al-Hakam ibn Nafi, who said: Arta'ah ibn al-Mundhir informed us, from Ubayd Allah ibn Rurayq, from Amr ibn al-Aswad, from Abu al-Darda, attributed to the Prophet. He said: “It is not narrated from Abu al-Darda except through this chain of transmission; Arta'ah alone narrated it.”
I say: He is trustworthy, as are all its other narrators, apart from Ubayd Allah ibn Rurayq. This is how it is written, with the relevant letter undotted. In Ibn Asakir, however, the second letter is dotted, and his nisbah is given as al-Alhani. I have not identified him. Yet al-Haythami said in al-Majma (5/24): “Al-Tabarani narrated it in al-Awsat, and its narrators are trustworthy.”
Note: In al-Zawa'id, the word appears vocalized as “munkabb,” derived from inkibab, or bending over; whereas in al-Majma and Ibn Asakir it appears as “mutakki’an,” derived from ittika, or reclining. Al-Haythami accordingly gave it the heading: “Chapter on Eating while Reclining.” And Allah knows best.
Then certain matters became clear to me. First, “Abd Allah ibn Rurayq” contains two errors. One is the copyist’s error; the correct reading is “Abd Allah ibn Ruzayq,” as found in a sound manuscript of al-Mu'jam al-Awsat (1/3/33, according to my numbering). The other is the error of one of the narrators, who confused his name; the correct form is “Ruzayq Abu Abd Allah.” Ibn Makula drew attention to this in al-Ikmal (4/54). This is likewise how he is listed in biographical works, such as al-Tarikh, al-Jarh, Ibn Hibban’s al-Thiqat (4/239), and others.