1993. The Journal of Arachnology 21 :156—158 MATING BIOLOGY RESOLVES TRICHOTOMY FOR CHELIFEROID PSEUDOSCORPION S (PSEUDOSCORPIONIDA, CHELIFEROIDEA) Mating behavior and spermatophore mor- tort' phenomena that cannot be observed in pre- phology have provided phylogenetically useful served specimens, behavior and fragile ejaculate s information for both vertebrate and invertebrate are seldom employed in phylogenetic studies . taxa (e . g., Proctor 1992a; Alberti et al . 1991; This is unfortunate because they often contain Prum 1990) . However, because they are transi- characters potentially helpful for resolving po - Table 1 .— Spermatophore morphology, mating behavior and male morphology in cheliferoid pseudoscorpions . (+) = character present; (—) = character absent. Characters pushes pulls s sperm in Sperma- over Rams 9's tophore sperma- horn genital Family Species droplet tophore organs opening Reference Chernetidae Epactiochernes tumidus (Banks) + + Weygoldt 1966a Chernes cimicoides (Fabricius) + + Weygoldt 1966b Dendrochernes morosus (Banks) + + Weygoldt 197 0 Lustrochernes pennsylvanicus (Ellingsen) + + - Weygoldt 197 0 Americhernes oblongus (Say) + + Weygoldt 1970 Parachernes litoralis Muchmore Alteri + + Weygoldt 1970 Cheliferidae Dactylochelifer latreille i (Leach) + + + Weygoldt 1966b Chelifer cancroides (Linnaeus) + + + Weygoldt 1966b Rhacochelifer disjunctu s (Koch) + — + + Weygoldt 197 0 Hysterochelifer meridianus (Koch) + + + Weygoldt 1970 Hysterochelifer tuberculatus (Lucas) + + + Weygoldt 197 0 Parachelifer superbus Hoff + + + Weygoldt 197 0 Atemnidae Paratemnoides braunsi (Tullgren) + — Weygoldt 1970 Atemnus politus (Simon) + Weygoldt 1969a Withiidae Withius subpiger Simon + — Weygoldt 1969b 156 RESEARCH NOTES 157 lychotomies that have proven intractable to tra- ical guidance has some advantage over physical ditional morphological approaches . As well, un- contact for these males (e. g., reduced likelihood like the usual alternatives of electrophoretic or of palp damage, greater guarantee of female in- DNA analyses, characters resulting from studies terest in mating) . Another apotypic behavior in of mating biology are evolutionarily interesting the Cheliferidae is the male's use of his foreleg s in themselves. to push sperm into the female genital opening Because of the diversity of sperm transfer be- after she has mounted the spermatophore (Tabl e havior and spermatophore morphology present 1); no other cheliferoids do this, although ther e in pseudoscorpions (Weygoldt 1969a), this grou p is often extended contact between male and fe- is likely to respond well to phylogenetic resolu- male after the female takes up sperm (e. g., Wey- tion using mating characters. In his recent cla- goldt 1970). Adaptive explanations for these and distic study, Harvey (1992) ascribed two repro- other reproductive characters will be possible only ductive synapomorphies to the superfamil y after studying their effects on male fitness . Cheliferoidea: production of spermatophores with This project was supported by a Natural Sci- complex rather than simple sperm masses an d ences and Engineering Research Council of Can - transfer of sperm during mating dances rather ada Postdoctoral Fellowship . I am grateful to than without pairing between the sexes . Within Mark Harvey for his encouragement and gen- the Cheliferoidea, the families Cheliferidae , erosity with his unpublished phylogeny. The Chernetidae and Atemnidae were differentiate d manuscript was improved by comments from M . from the Withiidae by synapomorphies of leg Harvey and V. F. Lee. morphology; however, Harvey found no char- acters to resolve the trichotomy formed by th e first three families . In recent literature reviews LITERATURE CITED (Proctor 1992b) I turned up several features o f Alberti, G ., N. A. Fernandez G. Kummel. 1991 . cheliferoid mating biology that both help to re - Spermatophores and spermatozoa of oribatid mite s solve this trichotomy and suggest adaptive sce- (Acari: Oribatida) . Part II: Functional and syste- narios for the evolution of mating behavior i n matical considerations . Acarologia, 32:435-449. this superfamily . Harvey, M. S. 1992 . The phylogeny and classification : Arachnida) . Table 1 lists characteristics of spermatophore of the Pseudoscorpionida (Chelicerata Invert. Taxonomy, 6:1373-1435 . morphology, male anatomy and mating behavio r Proctor, H. C. 1992a. Sensory exploitation and th e for species in the four families of the Chelifer- evolution of male mating behaviour : a cladistic test oidea. Spermatophore stalks of the Chernetida e using water mites (Acari: Parasitengona). Anim. Be- and Cheliferidae apomorphically possess a larg e hay., 44:745-752. droplet of apparently hypotonic liquid that caus- Proctor, H . C. 1992b . The evolution of sperm transfer es the sperm packet to swell and expel its con - behaviour in water mites (Acari: Parasitengona) . Ph. tents into the female genital atrium (Weygoldt D. dissertation; University of Toronto, Toronto , 1975). This synapomorphy allows the Chelifer- Ontario, Canada . oidea to be resolved from Harvey's (1992) ar- Prum, R. O. 1990. Phylogenetic analysis of the evo- lution of display behavior in the Neotropical man- rangement of [Withiidae (Cheliferidae + Cher- akins (Ayes : Pipridae). Ethology, 84:202-231. netidae + Atemnidae)] to [Withiidae (Atemnidae Weygoldt, P . 1966a. Mating behaviour and sper- (Cheliferidae + Chernetidae))]. Other aspects o f matophore morphology in the pseudoscorpion Din- mating biology provide phylogenetic and evo- ocheirus tumidus Banks (Cheliferinea, Chernetidae) . lutionary insight . Males of the Cheliferidae apo- Biol. Bull., 130:462-467. morphically possess genital sacs (ram's horn or- Weygoldt, P. 1966b . Vergleichende Untersuchunge n gans) that are everted after spermatophore zur Fortpflanzungsbiologie der Pseudoskorpione . deposition to attract the females, presumabl y Beobachtungen fiber das Verhalten, die Samentiber- through pheromones on their surface (Weygoldt tragungsweisen and die Spermatophoren einige r 1969a). Concomitant with the evolution of ram' s einheimischen Arten. Z. Morph. Okol . Tiere, 56 : 39-92. horn organs is loss of the male behavior of pulling Weygoldt, P. 1969a. The Biology of Pseudoscor- females over spermatophores, which is presen t pions. Harvard University Press, Cambridge . in the other three cheliferoid families (Table 1). Weygoldt, P. 1969b. Paarungsverhalten and Samen- This suggests that pheromonal attraction of the iibertragung beim Pseudoskorpion Withius subruber female replaced physical manipulation in th e Simon (Cheliferidae). Z. Tierpsychol., 26:230-235. Cheliferidae and raises the possibility that chem - Weygoldt, P. 1970. Vergleichende Untersuchunge n 158 THE JOURNAL OF ARACHNOLOGY zur Fortpflanzungsbiologie der Pseudoskorpione II . Heather C. Proctor: Department of Biological Z. Zool. Syst. Evolutionsforsch ., 8:241-259. Sciences, University of Calgary, Calgary, Al- Weygoldt, P. 1975 . Die indirekte Spermatophoren- berta T2N 1N4, Canada. iibertragung bei Arachniden . Verh. Deutschland, Manuscript received 20 November 1992, revised 5 Marc h Zool. Ges., 1974:308-313. 1993..