Caribboecetes progreso, a new species of sand-dwelling amphipod (Amphipoda: Corophiidea: Ischyroceridae) from the Gulf of Mexico, with a key for the genus Author Paz-Ríos, Carlos E. Author Ardisson, Pedro-Luis text Zootaxa 2013 3652 3 370 380 journal article 10.11646/zootaxa.3652.3.5 caefd0ae-c96f-42b7-ab38-c314fba36ac6 1175-5326 217037 3A45303E-EAF4-4299-962E-2CD745A48AF3 Key to species of Caribboecetes (modified from Just 1984) 1 Basis of gnathopod 2 with strongly triangular upward anterolateral flange......................................... 2 - Basis of gnathopod 2 without strongly triangular upward anterolateral flange...................................... 3 2 Rostrum not reaching beyond eyelobes; cephalon and first 4–5 pereonites dorsally with transverse rows of densely polyflagel- late setules; coxal plate and basis of pereopod 7 with densely setose lateral surface................. C. progreso sp. nov. - Rostrum reaching beyond eyelobes; cephalon and pereon with a few scattered simple setules; coxal plate 7 and basis of pereo- pod 7 with smooth lateral surface.................................................................... C. justi 3 Cephalon and first 3–5 pereonites with transverse rows of setules dorsally......................................... 4 - Cephalon and pereon at most with scattered dorsal setules..................................................... 5 4 Eyelobes with apical projection; peduncular article 5 and flagellar article 1 of antenna 2 with dorsolateral setae in a single dis- tinct row; coxal plate and basis of pereopod 7 with densely setose lateral surface........................ C. jenikarpae - Eyelobes apically rounded; dorsolateral setae on peduncular article 5 of antenna 2 not in a single row; coxal plate 7 and basis of pereopod 7 with smooth lateral surface....................................................... C. barbadensis 5 Rostrum curved strongly downward; article 1 of antenna 1 with broad, marginally setose lateral “wing”...... C. pterycornis - Rostrum straight; article 1 of antenna 1 normal................................................... C. intermedius