Laudator Temporis Acti

In response to the last post, E.J. Moncada (via email) adduces Richmond Lattimore, Themes in Greek and Roman Epitaphs (Urbana: University of Illinois Press, 1962), p. 107: μή, δέομαι, γελάσῃς εἰ κυνός ἐστι τάφος (Please do not laugh because this is a dog's grave.) = Kaibel, Epigrammata Graeca 627, 2 (near Florence).

This seems similar to an epigram translated by J. W. Mackail, as LIV in his collection Select Epigrams from the Greek Anthology (1890):

Thou who passest on this path,
If haply thou dost mark this monument,
Laugh not, I pray thee, though it is a dog's grave.
Tears fell for me, and the dust was heaped above me
By a master's hand.

Also in Mackail's collection are LV (by Tymnes):

Here the stone says it holds the white dog from Melita, the most faithful guardian of Eumelus; Bull they called him while he was yet alive; but now his voice is prisoned in the silent pathways of night.

and LVII (by Simonides):

Surely even as thou liest dead in this tomb I deem the wild beasts yet fear thy white bones, huntress Lycas; and thy valour great Pelion knows, and splendid Ossa and the lonely peaks of Cithaeron.

Mackail's LV is number 7.211 in the Greek Anthology:

Τῇδε τὸν ἐκ Μελίτης ἀργὸν κύνα φησὶν ὁ πέτρος
  ἴσχειν, Εὐμήλου πιστότατον φύλακα.
Ταῦρόν μιν καλέεσκον, ὅτ᾽ ἦν ἔτι· νῦν δὲ τὸ κείνου
  φθέγμα σιωπηραὶ νυκτὸς ἔχουσιν ὁδοί.

I have not yet tracked down the standard citations of Mackail's LIV and LVII.

Julia Lougovaya-Ast, in a review of Reinhold Merkelbach and Josef Stauber, Steinepigramme aus dem griechischen Osten. Band 4: Die Südküste Kleinasiens, Syrien und Palaestina (München/Leipzig: K.G. Saur, 2002), writes:

18/01/28, from Termessos, is a very interesting inscription on a small sarcophagus of a dog named Stephanos. The epitaph seems to have comprised three epigrams, of which the first is largely lost, but the following two survive intact:

This is the tomb of the dog, Stephanos, who perished,
Whom Rhodope shed tears for and buried like a human (vv. 4-5).
I am the dog Stephanos, and Rhodope set up a tomb for me (v. 6).

The small sarcophagus was found near the inscribed sarcophagus of Rhodope herself.

Corpus Inscriptionum Latinarum 6.29896 is an epitaph for a dog named Margarita (Pearl):

Gallia me genuit nomen mihi divitis undae /
concha dedit formae nominis aptus honos /
docta per incertas audax discurrere silvas /
collibus hirsutas atque agitare feras /
non gravibus vinc(u)lis unquam consueta teneri /
verbera nec niveo corpore saeva pati /
molli namque sinu domini dominaeque iacebam /
et noram in strato lassa cubare toro /
et plus quam licuit muto canis ore loquebar /
nulli latratus pertimuere meos /
sed iam fata subii partu iactata sinistro /
quam nunc sub parvo marmore terra tegit /
Margarita

It should be noted that Sauvage Noble's second example is a variation on Catullus' dirge for Lesbia's sparrow (3, Lugete, o Veneres Cupidinesque).

I don't have access to Courtney's Musa Lapidaria, but if I recall correctly, it has extensive notes, and probably cites everything above and more.