Acromares banksy
Acromares banksi Goodnight & Goodnight, 1942, from original description









Acromares Goodnight & Goodnight 1942 is a genus of the Neotropical family Cosmetidae, subfamily Cosmetinae with two species from the Neotropical region.


Acromares Goodnight & Goodnight, 1942a: 2.[1]

Etymology Edit

The original authors do not say, but plausibly latinised Acro- from ἄκρων (ákrōn) meaning the extremity, peak or tip, possibly combined with latin mās meaning male (nominative plural marēs), if so maybe alluding to the robust spines on the scutum.

Placement Edit

Originally placed in Cosmetidae, Cosmetinae.

Type speciesEdit

Acromares banksi Goodnight & Goodnight 1942, by original designation.


The genus is notable for males having "enlarged chelicerae and rows of spines on the patella and tibia of the fourth leg" (Goodnight & Goodnight, 1942, p.2).

Specifically, Goodnight & Goodnight, 1942, say (p.2). "A pair of robust spines on the fourth area of the abdomen, first, second, third, and fifth areas and free tergites unarmed. Third and fourth legs larger than the first and second. Secondary sexual characteristics of the male in the enlarged chelicerae and rows of spines on the patella and tibia of the fourth leg. The spines on the patella in one row, and on the tibia in two rows of large spines and three rows of small spines. Eye tubercle low, wider than long. Tarsal joints : 6-10-7-8. End group of articulations of first and second legs 3-3. GENOTYPE.-Acromares banksi, new species. This genus differs from other genera of this subfamily in the arrangement of the dorsal spines and in the number of tarsal joints."



See also Erginulus clavotibialis (Pickard-Cambridge, 1905) (and synonyms) from various Central American localities[3], and Cynorta goodnightorum Beutelspacher, 1988 from Mexico, Veracruz. These may be congeners with remaining Acromares.

Already transferred:

This species was described from a single female holotype collected in Colombia, and indicated "a pair of sharp spines on the fourth area" of the dorsal scutum. The form of these contrasts with Acromares, which was previously diagnosed by Goodnight & Goodnight 1942 (p.2) as having "A pair of robust spines on the fourth area of the abdomen" and later as "heavy spines" for both males and females of its type species A. banksi, in neither case indicating sharp spines. Similarly, a second species Acromares vittatum Goodnight & Goodnight, 1942 was also later diagnosed (p.7) as having "a pair of robust spines on the fourth area". In contrast for Acromares lateralis Goodnight & Goodnight, 1943 (p.2), its supposedly "sharp spines" did not agree in their structure to the generic diagnosis, nor did the single female type specimen display any of the sexually dimorphic features of males which might have better indicated generic placement (such as the "enlarged chelicerae and rows of spines on the patella and tibia of the fourth leg" (Goodnight & Goodnight, 1942, p.2)). Furthermore, the distant geographic origin of A lateralis Goodnight & Goodnight, 1943 in Colombia (to other existing species of Acromares in North/Central America) should have led to suspicion about its placement as congeneric. Much later, Medrano & Kury (2017) have revised A lateralis as a junior synonym of Eulibitia scalaris (Sørensen in Henriksen, 1932) (p.3), a genus re-characterised as having a "Posterior margin of scutum armed with two small paramedian tubercles (except for E. maculata)" (Medrano & Kury, p.5), who say "However, the Colombian species differs from the others by having two tubercles on the posterior margin of DS instead of scutal area IV, showing no apparent congeneric relation. This is reinforced by the disjointed distribution of this species compared to the other two." Also they say (p.48) "Goodnight & Goodnight (1943) described Acromares lateralis and placed it in that genus because they thought that the outstanding tubercles of the dorsal scutum were localized in area IV. However, examination of a photograph of the type material allows us to conclude that the tubercles are on the posterior margin of the scutum instead of on area IV and to recognize this species as a synonym of E. scalaris comb. nov."


  1. 1.0 1.1 Goodnight, Clarence J. & Marie L. Goodnight, 1942b. New and little known Phalangida from Mexico. American Museum Novitates, New York, 1163: 1-16. [Publication date is 13 February 1942].
  2. Goodnight, Clarence J. & Marie L. Goodnight, 1942e. Phalangids from Central America and the West Indies. American Museum Novitates, New York, 1184: 1-23. [Publication date is 12 August 1942].
  3. Kury, A.B. (2003) Annotated catalogue of the Laniatores of the New World (Arachnida, Opiliones). Revista Ibérica de Aracnología, vol. especial monográfico, 1, 1–337. [Issued 31 May 2003].