Belongs within: Carangidae.
The Echeneoidea are a clade of pelagic marine fishes sharing elongate larvae with late dorsal fin completion.
Echeneoidea
|--+--Rachycentron [Rachycentridae]NE12
| | `--R. canadus (Linné 1766)M58 [=Gasterosteus canadusM58; incl. R. pondicerianumJR10]
| `--Coryphaenidae [Ductoridae]P93
| |--Ductor vestenae (Volta 1796)P93
| |--Coryphaena Linnaeus 1758NE12, L58
| | |--C. equiselis Linnaeus 1758LD09
| | |--C. hippurus Linnaeus 1758C02b
| | |--C. novacula Linnaeus 1758L58
| | `--C. pompilus Linnaeus 1758L58
| `--AstrodermaL43
| |--A. coryphaenoides [incl. Diana semilunata]L43
| `--A. plumbeum Lowe 1843L43
`--Echeneidae [Echeneiformes]NE12
|--Phtheirichthys lineatus (Menzies 1791) [=Echeneis lineatus]M58
|--Opisthomyzon glaronensis (Wettstein 1886)P93
|--Echeneis Linnaeus 1758L58
| |--E. carpathica Szajnocha 1926P93
| |--E. naucrates Linnaeus 1758C02a [=Leptecheneis naucratesM58]
| `--E. naucratoidesC02a
`--RemoraC02a
|--R. albescens (Schlegel 1850) [=Echeneis albescens]M58
|--R. brachyptera (Lowe 1839)C02a
`--R. remora (Linnaeus 1758)C02a [=Echeneis remoraM58]
*Type species of generic name indicated
References
[C02a] Collette, B. B. 2002a. Remoras and sharksuckers. Family Echeneidae. In: Collette, B. B., & G. Klein-MacPhee (eds) Bigelow and Schroeder’s Fishes of the Gulf of Maine 3rd ed. pp. 406–409. Smithsonian Institute Press: Washington.
[C02b] Collette, B. B. 2002b. Dolphinfishes. Family Coryphaenidae. In: Collette, B. B., & G. Klein-MacPhee (eds) Bigelow and Schroeder’s Fishes of the Gulf of Maine 3rd ed. pp. 409–411. Smithsonian Institute Press: Washington.
[JR10] Jordan, D. S., & R. E. Richardson. 1910. Check-list of the species of fishes known from the Philippine archipelago. Bureau of Printing: Manila.
[LD09] Li, B., A. Dettaï, C. Cruaud, A. Couloux, M. Desoutter-Meniger & G. Lecointre. 2009. RNF213, a new nuclear marker for acanthomorph phylogeny. Molecular Phylogenetics and Evolution 50: 345–363.
[L58] Linnaeus, C. 1758. Systema Naturae per Regna Tria Naturae, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. Tomus I. Editio decima, reformata. Laurentii Salvii: Holmiae.
[L43] Lowe, R. T. 1843. On the fishes of Madeira. Proceedings of the Zoological Society of London 11: 81–95.
[M58] Munro, I. S. R. 1958. The fishes of the New Guinea region: a check-list of the fishes of New Guinea incorporating records of species collected by the Fisheries Survey Vessel “Fairwind” during the years 1948 to 1950. Papua and New Guinea Agricultural Journal 10 (4): 97–369 (reprinted: 1958. Territory of Papua and New Guinea Fisheries Bulletin no. 1).
[NE12] Near, T. J., R. I. Eytan, A. Dornburg, K. L. Kuhn, J. A. Moore, M. P. Davis, P. C. Wainwright, M. Friedman & W. L. Smith. 2012. Resolution of ray-finned fish phylogeny and timing of diversification. Proceedings of the National Academy of Sciences of the USA 109 (34): 13698–13703.
[P93] Patterson, C. 1993. Osteichthyes: Teleostei. In: Benton, M. J. (ed.) The Fossil Record 2 pp. 621–656. Chapman & Hall: London.