Amphiarius rugispinis

{{Short description|Species of fish}}

{{Speciesbox

| name = Softhead sea catfish

| status = LC

| status_system = IUCN3.1

| status_ref = {{cite iucn|author=Marceniuk, A.P.|author2= Betancur, R.|author3= Giarrizzo, T. |author4= Fredou, F.L. |name-list-style=amp |year=2015 |title= Notarius rugispinis|page= e.T197079A2478900 |doi=10.2305/IUCN.UK.2015-2.RLTS.T197079A2478900.en |access-date=21 March 2024}}

| taxon = Amphiarius rugispinis

| authority = (Valenciennes, 1840)

| synonyms = *Arius rugispinis Valenciennes, 1840

• Cathorops rugispinis (Valenciennes, 1840)
• Hexanematichthys rugispinis (Valenciennes, 1840)
• Notarius rugispinis (Valenciennes, 1840)
• Tachysurus atroplumbeus Fowler, 1931

}}

Amphiarius rugispinis, the softhead sea catfish, is a species of sea catfish which is found along the northern coast of South America. It is found chiefly in turbid waters of estuaries and around river mouths; it originates from brackish and marine waters of Trinidad and Tobago, Guyana, Suriname, French Guiana, and Brazil.{{cite journal |url=http://www.mapress.com/zootaxa/2007f/zt01416p126.pdf |title=Systematics of the family Ariidae (Ostariophysi, Siluriformes), with a redefinition of the genera|first=Alexandre P.|last=Marceniuk|author2=Menezes, Naércio A.|journal=Zootaxa|volume=1416|pages=1–126|year=2007|doi=10.11646/zootaxa.1416.1.1 }} This species grows to about {{cvt|45|cm|in}} TL. Reproduction in A. rugispinis appears to be between September and November. The diameter of the eggs is 14–{{convert|15|mm|in|frac=16}}, numbering about 30–35 per female.