Hippocampus ingens, Girard 1858

Sara A. Lourie, Riley A. Pollom & Sarah J. Foster, 2016, A global revision of the Seahorses Hippocampus Rafinesque 1810 (Actinopterygii: Syngnathiformes): Taxonomy and biogeography with recommendations for further research, Zootaxa 4146 (1), pp. 1-66: 29

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Hippocampus ingens


H. ingens Girard 1858 

English common names. Pacific Seahorse, Giant seahorse.

Synonyms. H. gracilis Gill 1862  , H. ecuadorensis Fowler 1922  , H. hildebrandi Ginsburg 1933  .

Distribution. Colombia, Costa Rica, Ecuador (including the Malpelo, Cocos and Galapagos Islands), El Salvador, Guatemala, Honduras, Mexico, Nicaragua, Panama, Peru, USA (California).

Lectotype: USNM 982. Paralectotypes: MCZ 35914 [ex USNM 982], UMMZ 118063, USNM 214485 [ex USNM 982] (2).

Type locality. San Diego , USA. 

Notes. See Fritzsche (1980) for refutations of all three synonyms. Anecdotal reports exist of H. ingens  individuals being seen by fishers as far north as Barkley Sound, British Columbia (W. Harstad, pers. comm. 2014; A. Vincent, pers. comm. 2014). Genetic studies indicate low overall diversity within this species relative to other seahorses based on mtDNA cyt b (587 bp, 0.8% Tamura-Nei distance) and control region (340 bp, 1.2% Tamura-Nei distance) and tRNA-pro and control region (428 bp, 0.39% nucleotide diversity (q P) sequences ( Sanders et al. 2008; Saarman et al. 2010).