Key to species of the genus Longicyatholaimus The present identification key is an updated and modified version of that proposed by Hopper (1972). 1. Punctuations in lateral regions arranged in longitudinal rows.................................................. 2 - Punctuations in lateral regions not arranged in longitudinal rows............................................... 4 2. Body 2.6 mm long; amphideal fovea with five turns...................................... L. trichurus (Cobb, 1898) - Body 700 µm in length (703–992 µm)..................................................................... 7 6. Cephalic setae length equal to ⅓ of the head width; labial setae length equal to ¼ of cephalic setae................................................................................................ L. longicaudatus (de Man, 1876) - Cephalic setae length equal to ½ of the head width; labial setae length equal to ⅓–½ of cephalic setae................................................................................................... L. marilynae Hopper, 1972 7. Distal extremity of spicules without large spines (at most with small denticles).................................... 8 - Distal extremity of spicules with 3–13 large spines.......................................................... 9 8. Amphideal fovea> than one head diameter from anterior extremity, amphideal fovea with four turns; single longitudinal row of pores in the cervical region....................................................... L. cervoides Vitiello, 1970 - Amphideal fovea

Published as part of Balsamo, Maria, 2017, A re-description of Longicyatholaimus maldivarum Gerlach, 1964 (Nematoda, Cyatholamidae) with an emended identification key of the genus, pp. 96-108 in Zootaxa 4323 (1) on page 105, DOI: 10.11646/zootaxa.4323.1.7, http://zenodo.org/record/897397