Key to species of Pselaphomorphus, based on males 1 Head triangular (Fig. 8 A), base of the antennal tubercle not longer that the eye..................................... 2 - Head pear-shaped (Fig. 4 A) to elongate (Fig. 5), base of the antennal tubercle longer than the eye diameter............. 12 2 Antennal clava evident; antennomers 7 to 11 dictintively wider (Fig. 6 A)......................................... 3 - Antennal clava not evident (Fig. 4 A)...................................................................... 8 3 All antennomeres quadrate (Fig. 8 A); body length less than 2.0 mm.............................................. 4 - Clava antennomeres elongate (Fig. 4 A) antennomere 7 at least twice as long as antennomere 6........................ 5 4 Aedeagal median lobe divided medially into four arms (Figs. 8 B, 8C). Longer arm extending upward and curved from left to middle in dorsal view. Accessory lobes absent................................. Pselaphomorphus breviantennae n. sp. - Aedeagal median lobe divided apically as short as accessory lobes (Figs. 13 C, 13D). Accessory lobes present..................................................................................... Pselaphomorphus fluminosus n. sp. 5 Pronotum with obtuse spines between the lateral lobes and the basal lobe (Fig. 16 A)................................ 6 - Pronotum without spines................................................................................ 7 6 Median lobe of aedeagus flattened, complete, accessory lobe complete...... Pselaphomorphus tucumanensis n. sp. (Fig. 32) - Median lobe of aedeagus divided into two arms, accessory lobes divided...... Pselaphomorphus longiceps Raffray (Fig. 16) 7 Phallobase asymmetric (Fig. 15 B), median lobe short and slender. Two accessory lobes shorter than median lobe..................................................................................... Pselaphomorphus incorum n. sp. - Phallobase symmetric (Fig. 23 B), median lobe divided into two arms: left arm laminate, right arm cylindrical, located medi- ally; accessory lobe divided into two arms with acute apices.................... Pselaphomorphus montsineryensis n. sp. 8 Pronotal lobes triangular (Fig. 26 A), basally rounded; antennomere 6 small and quadrate, 7 elongate; elytra with the basal ridge weak, discal depression and humeral teeth absent................................. Pselaphomorphus parki n. sp. - Pronotal lobes trapezoidal or rectangular (Fig. 30 A); antennomere 6 small and elongate, antennomere 7 elongate and at least three times longer than 6; elytra with strong basal ridge discal depression and humeral teeth present.................... 9 9 Discal depression extending slightly beyond the humeral tooth (Fig. 12 A).............. Pselaphomorphus chandleri n. sp. - Discal depression not extending beyond the humeral tooth.................................................... 10 10 Pronotal disc rectangular (Fig. 24 A); genitalia short (0.6 mm) and symmetrical ventrally membranous, median lobe complete, not divided (Figs. 24 B, 24C)................................................ Pselaphomorphus motschulskyi n. sp. - Pronotal disc oval, genitalia globose or narrow, divided or with accessory lobes present............................. 11 11 Phallobase rounded and globose, medially divided into two asymmetrical arms (Figs. 18 B, 18C)............................................................................................. Pselaphomorphus macrommatus n. sp. - Phallobase regular, narrow and symmetrical, median lobe laminate, accessory lobe cylindrical (Figs. 30 B and 30C)............................................................................... Pselaphomorphus simplicipenis n. sp. 12 Head elongate: base of the antennal tubercle longer than eye diameter; aedeagus with two median lobes (Fig. 5)......... 13 - Head pear-shaped: base of the antennal tubercle as long as eye diameter; aedeagus with one median lobe (Fig. 22)........ 14 13 Body color and pilosity amber (Fig. 5 A); aedeagus with two accessory lobes, one divided (Figs. 5 B, 5C)........................................................................................ Pselaphomorphus agametopus n. sp. - Body color reddish and pilosity bright yellow (Fig. 17 A); aedeagus with one accessory lobe surrounding median lobes (Figs. 17 B, 17C).............................................................. Pselaphomorphus longissimus n. sp. 14 Antennae with five segmented clava; antennomere 7 twice as long as antennomere 6 and distinctively wider (Fig. 22 A)... 15 - Antennae without evident clava; antennomere 7 not longer than 6 and of similar width (Fig. 31 A)..................... 17 15 Pronotal lateral lobes triangular with the basal region obtuse; pronotal disc oval (Fig. 22 A).............................................................................................. Pselaphomorphus microphthalmus Raffray - Pronotal lobes triangular with the basal region rounded (Figs. 6 A, 27A)......................................... 16 16 Obtuse spines present between lateral and basal lobes of pronotum (Fig. 27 A.)............ Pselaphomorphus raffreyi n. sp. - Pronotum without spines between lateral and basal lobes (Fig. 6 A).................. Pselaphomorphus azuayensis n. sp. 17 Phallobase irregular (Figs. 19 B, 31B)..................................................................... 18 - Phallobase regular (Figs. 9 C, 21B), some species with the head sulcus wider than eye radius (Fig. 9 B)................. 21 18 Accessory lobe of the aedeagus as long as half of the median lobe (Figs. 19 B, 19C, 28B, 28C)....................... 19 - Accessory lobe of aedeagus shorter than half of the median lobe (Figs. 14 B, 14C, 31B, 30C)......................... 20 19 Accessory lobe membranous and laminate (Fig. 19)........................... Pselaphomorphus maldonadensis n. sp. - Accessory lobe of aedeagus, in dorsal view, long, straight and cylindrical, with the apex acute (Fig. 28 B)........................................................................................ Pselaphomorphus santaecrucis n. sp. 20 Accessory lobe of aedeagus, in dorsal view, rounded basally and acute apically, curved to right (Fig. 14 B)........................................................................................ Pselaphomorphus iguazuensis n. sp. - Accessory lobe short, less than one-third the length of median lobe (Fig. 31)............. Pselaphomorphus thayerae n. sp. 21 Body coloration reddish, pilosity clear or light yellow; antennomere length gradually increasing after 6................ 22 - Body coloration dark brown, pilosity bright yellow; antennomere length evenly increasing throughout (Fig. 21 A).................................................................................... Pselaphomorphus melanus n. sp. 22 Head longitudinal sulcus wider than eye radius (Fig. 9A, 9 B).................................................. 23 - Head longitudinal sulcus not wider than eye radius, fusiform (Figs. 4 A)......................................... 24 23 Head longitudinal sulcus rounded (Fig. 9A)....................................... Pselaphomorphus bruchi Raffray - Head longitudinal sulcus linear (Fig. 9 B).................................... Pselaphomorphus carenobothrus n. sp. 24 Mesotrochanter armed with acute spine that projects vertically, the spine longer than mesotrochanter width (Fig. 4 B)............................................................................. Pselaphomorphus acutispinosus n. sp. - Mesotrochanter triangular without projection or with weak projection not longer than mesotrochanter width............. 25 25 Accessory lobe of aedeagus present (Figs. 11 B, 11C, 25B, 25C)................................................ 26 - Accessory lobe of aedeagus absent (Figs. 7 C, 20B, 20C, 33B, 33C)............................................. 27 26 Accessory lobes short, cylindrical basally, and dorsal to two arms of median lobe (Fig. 10 B).................................................................................................. Pselaphomorphus cayenennsis n. sp. - Accessory lobe longer than median lobe, flattened (Fig. 24 B).......................... Pselaphomorphus newtoni n. sp. 27 Aedeagus in dorsal view parallel-sided throughout its length.................................................. 28 - Aedeagus in dorsal view becoming wider from mid point to apex............................................... 31 28 Aedeagus divided apically............................................................................. 29 - Aedeagus not divided apically; in lateral view curved dorsally beyond phallobase.................................. 30 29 Aedeagus apically divided into three short spines; in lateral view flat, not curved dorsally (Fig. 32 C).......................................................................................... Pselaphomorphus veracruzanus n. sp. - Aedeagus apically divided into two arms, median lobe inserted into circular structure at base (Fig. 6 C).......................................................................................... Pselaphomorphus bolivarensis n. sp. 30 Aedeagus in dorsal view straight, slightly curved at apex (Fig. 19 C)................. Pselaphomorphus mayaorum n. sp. - Aedeagus in dorsal view curved medially to right and apically to left (Fig. 33 C).......... Pselaphomorphus wagneri n. sp. 31 Aedeagus apically with two long arms projecting dorsally (Figs. 28 B, 28C).... Pselaphomorphus sculpturatus Motschulsky - Aedeagus apically rounded, lacking arms (Figs. 9 B, 9C).............................. Pselaphomorphus carltoni n. sp.

Published as part of Vásquez-Vélez, Laura M., 2016, Revision of the genus Pselaphomorphus Motschulsky, 1855 (Staphylinidae, Pselaphinae: Jubini), pp. 1-48 in Zootaxa 4107 (1) on pages 8-9, DOI: 10.11646/zootaxa.4107.1.1, http://zenodo.org/record/261931