Kurtidae, Bleeker, 1859

Fraser, Thomas H., 2013, A new genus of cardinalfish (Apogonidae: Percomorpha), redescription of Archamia and resemblances and relationships with Kurtus (Kurtidae: Percomorpha), Zootaxa 3714 (1), pp. 1-63 : 55-56

Family Kurtidae

Diagnosis. Same as given under the treatment of the genus.

Summary

The Apogonidae and Kurtidae are monophyletic families. The assertion of sister relationship between Archamia and Kurtus is rejected. Similarities between Archamia and Kurtus are superficial and have arisen independently. Known osteology and morphology of Archamia have no clearly identified morphological synapomorphies supportive of a sister relationship with Kurtus . Prokofiev (2006) and Thacker (2009) may have been convinced by resemblance of characters rather than synapomorphies of homologous characters. Apomorphic characters of Kurtus are unusual, making its nearest living phylogenetic relative uncertain. Other characters are homoplasic, or often plesiomorphic. A single possible synapomorphic character in kurtid gill arches is shared with at least three other families of percomorph fishes ( Gerreidae , Glaucosmatidae and some Pempheridae ) and apogonids. Interpretation of this character may be useful at some higher level, but for now it is uncertain. Ultrastructure of eggs may contain possible synapomorphic characters, but lack of information hampers interpretation and requires additional study. No morphological synapomorphy was the exclusive domain of apogonids and kurtids.

There are intriguing morphological characters that point to carangoid fishes as a possible sister group with Kurtidae and should be confirmed or rejected.

Betancur-R et al. (2013, p. 14) stated... “There is also morphological evidence supporting a close relationship between gobids and apogonids 108,109 as well as between kurtids and apogonids 110.” All three cited papers (108, Miller 1973; 109, Winterbottom 1993; 110 Johnson 1993) are part of this analysis. Miller’s only mention of apogonids was given above in the discussion of free neuromasts. Winterbottom concluded... “Three taxa emerge as potentially viable candidates for the status of the gobioid sister group-the gobiesocids (plus or minus the callionymoids), some subset of the trachinoids and some subset of the scorpaeniforms (especially the hoplichthyids).” Johnson noted... “There is, in fact, evidence suggesting that Kurtus may be closely related to the Apogonidae . The configuration of the dorsal gill-arch elements is remarkably similar to that of the apogonids.” “More detailed comparison of the ultrastructure and innervation of sensory papillae will be necessary to evaluate their homology in these groups. Another test of the Kurtus and apogonid hypothesis is available through detailed comparison of the eggs, both of which bear filaments around the micropyle that serve to bind the eggs together into a mass which is brooded in the mouth of apogonids and carried on the supraoccipital hook in Kurtus .” The molecular tree reported by Betancur et al. (2013, fig. 3) is not supported by their own citations for morphological support within the major branch of the hypothesized Kurtiformes .

Partial hypotheses from molecular trees showing some association between the apogonids and kurtids have yet to find a basis in morphological homologies that are unequivocal evidence of synapomorphic characters.