IGC 1962 Arc of the 6th Parallel South - EPSG:4697

WKT

GEOGCS["GCS_IGC_1962_6th_Parallel_South", 
	DATUM["D_IGC_1962_Arc_of_the_6th_Parallel_South", 
		SPHEROID["Clarke_1880_RGS", 6378249.145, 293.465]], 
	PRIMEM["Greenwich", 0.0], 
	UNIT["Degree", 0.0174532925199433]]

WKT2

GEOGCRS["GCS_IGC_1962_6th_Parallel_South", 
	DATUM["D_IGC_1962_Arc_of_the_6th_Parallel_South", 
		ELLIPSOID["Clarke_1880_RGS", 6378249.145, 293.465]], 
	PRIMEM["Greenwich", 0.0], 
	CS[ellipsoidal, 2], 
	AXIS["Latitude (lat)", north, 
		ORDER[1]], 
	AXIS["Longitude (lon)", east, 
		ORDER[2]], 
	ANGLEUNIT["Degree", 0.0174532925199433], 
	ID["EPSG", "4697"]]

Data from @esri/proj-codes

{
  "wkid": 4697,
  "latestWkid": 4697,
  "macro": "PE_GCS_IGC_1962_6TH_PARALLEL_S",
  "name": "GCS_IGC_1962_6th_Parallel_South",
  "wkt": "GEOGCS[\"GCS_IGC_1962_6th_Parallel_South\",DATUM[\"D_IGC_1962_Arc_of_the_6th_Parallel_South\",SPHEROID[\"Clarke_1880_RGS\",6378249.145,293.465]],PRIMEM[\"Greenwich\",0.0],UNIT[\"Degree\",0.0174532925199433]]",
  "wkt2": "GEOGCRS[\"GCS_IGC_1962_6th_Parallel_South\",DATUM[\"D_IGC_1962_Arc_of_the_6th_Parallel_South\",ELLIPSOID[\"Clarke_1880_RGS\",6378249.145,293.465]],PRIMEM[\"Greenwich\",0.0],CS[ellipsoidal,2],AXIS[\"Latitude (lat)\",north,ORDER[1]],AXIS[\"Longitude (lon)\",east,ORDER[2]],ANGLEUNIT[\"Degree\",0.0174532925199433],ID[\"EPSG\",\"4697\"]]",
  "description": "IGC 1962 Arc of the 6th Parallel South",
  "authority": "EPSG",
  "version": "6.8(9.2.0)",
  "deprecated": "no",
  "areaname": "Congo DR (Zaire) - 6th parallel south",
  "extent": {
    "slat": -7.36,
    "nlat": -3.29,
    "llon": 12.17,
    "rlon": 29.64
  }
}