Zilchia, PRETZMANN, 1968

Magalhães, Célio & Wehrtmann, Ingo S., 2025, Taxonomic revision and distribution of the freshwater crabs of the family Pseudothelphusidae (Decapoda, Brachyura) from Guatemala, with the descriptions of two new species and keys to the species of all genera, Zoosystema 47 (26), pp. 581-615 : 603

KEY TO GUATEMALAN SPECIES OF ZILCHIA PRETZMANN, 1968

1. G1 with apex oblong; field of apical spines well developed, open (not concealed by apical margins); cephalic surface distinctly curved towards cephalic side distally, cephalic lobe absent ................................................ 2

— G1 with apex narrow, slit-like; field of apical spines poorly developed, nearly concealed by apical margins; cephalic surface of distal portion nearly straight distally, with well-developed spiny cephalic lobe ( Fig. 10A, B... .......................................................................................................................... Z. germani Pretzmann, 1978

2. G1 with mesial process bearing upper margin serrate; cephalic process as conical spine approximately as large as the mesial process; apex with mesocaudal margin entirely bordered by row of teeth ( Fig. 11 F-I) ................ ............................................................................................................................................ Z. coronata n. sp.

— G1 with mesial process bearing upper margin smooth; cephalic process as short conical spine distinctly smaller than mesial process; apex with mesocaudal margin unarmed ( Fig. 10C, D)..................................................... .............................................................................................................. Z. falcata Rodríguez & Hobbs, 1989