Stag beetles range in size from less than 4 mm to 10 cm. Many adult males possess greatly enlarged, curving mandibles that are sometimes used in combat with male opponents during fights to establish dominance. In the males, development of the mandibles is usually allometric, that is, the size of the mandibles is proportional to the size of the body. Those males with the largest mandibles are referred to as "male majors" and those with the smallest mandibles are called "male minors."

Length 8.0-90.0 mm. Shape usually weakly convex, subdepressed, or cylindrical, elongate. Color usually black to reddish brown, sometimes testaceous or metallic. Scales often present on dorsum. Head prognathus, not deflexed. Antennae geniculate or straight, 10-segmented, with 3-7 segmented club; first segment elongate and often subequal to remaining segments. Eyes with eucone or acone ommatidia; eye canthus present or absent. Clypeus and labrum fused to frons. Mandibles produced beyond apex of labrum, usually prominent (males often with large, curved, elongate mandibles). Maxillae with 4-segmented palpi; labium with 3-segmented palpi. Pronotum variably convex, with or without horns and tubercles. Elytra weakly convex. Scutellum exposed, triangular or parabolic. Pygidium concealed by elytra or only weakly exposed. Legs with coxae transverse, mesocoxae separated; protibiae dentate on outer margin, apex with one spur; meso- and metatibia with ridges, apex with 2 spurs; spurs mesad, adjacent (not separated by basal metatarsal segment); tarsi 5-5-5; claws equal in size, simple; empodium present or absent, extending weakly beyond fifth tarsal segment or extending nearly one half claw length, with 2 to several setae. Abdomen with 5 or 6 visible sternites; 8 functional abdominal spiracles situated in pleural membrane. Wings if well developed with M-Cu loop and two, apical, detached veins; flightlessness and brachyptery common. Male genitalia with paired symmetrical parameres and a median lobe. Median lobe often terminating in a ribbon-like permanently everted internal sac (Lucaninae only). References: Didier and Seguy 1953; Scholtz 1990.

Classification Status
The family Lucanidae has long been considered one of the most primitive groups in the Scarabaeoidea (Crowson 1967; Howden 1982; Ritcher 1966), and scarabaeoid classifications and evolutionary hypotheses have generally regarded the Lucanidae as basal to all scarabaeoids (Howden 1982; Iablokoff-Khnzorian 1977; Lawrence and Newton 1995). However, based on comparison with "primitive" scarabaeoid groups, Scholtz et al. (1994) hypothesized that the scarabaeoid family Glaresidae, rather than the Lucanidae, is the most primitive scarabaeoid. According to this hypothesis, the Lucanidae is a member of a clade that includes the Passalidae, Diphyllostomatidae, Glaphyridae, Trogidae, Pleocomidae, and Bolboceratinae (Geotrupidae). More recent phylogenetic analyses cast doubt on both of these hypotheses, and place Lucanidae in an intermediate clade with Glaresidae and Trogidae (Smith et al. 2006).

Prior to the taxonomic elevation of the genus Diphyllostoma to the family Diphyllostomatidae (Holloway 1972), the Lucanidae was hypothesized to be most closely related to the Passalidae (Howden 1982). Based on shared characters, it is now thought that the Lucanidae is most closely related to the Diphyllostomatidae (Caveney 1986; Browne and Scholtz 1995).

The world Lucanidae (about 1500 species) have been treated in checklists by Benesh (1960) and Maes (1992) and in illustrated catalogs by Didier and Seguy (1953),and Mizunuma and Nagai (1994), and Fujita (2010). The latter is spectacular for its colored plates of the world stag beetle fauna, however it contains numerous errors with respect to the indentification of New World stag beetles. Benesh (1960) recognized eight subfamilies, four of which occurred in the United States. Howden and Lawrence (1974) and Kikuta (1986) proposed significant changes of genera within subfamilies. Based on the work of Holloway (1960, 1968, 1969), the most recent subfamilial classification is followed here, with three subfamilies now recognized as occurring in North America: Aesalinae, Syndesinae, and Lucaninae. One member of the remaining lucanid subfamily, Lampriminae, occurs in South America. The subfamily Penichrolucaninae was formerly used for two genera of aberrant termitophilous lucanids, but these are now considered to be derived members of Lucaninae, tribe Figulini (Bartolozzi 1989).

New World subfamilies and genera
(click on generic names for information)


The world fauna consists of about 1500 species (Mizunuma and Nagai 1994) with more species found in Asia than in other areas. Keys to adults: Benesh 1946; Howden and Lawrence 1974; Ratcliffe 1991. Keys to larvae: Ritcher 1966. Catalogs of North American species: Benesh 1960; Blackwelder and Arnett 1974. Biology: Milne 1933; Hoffman 1937, Paulsen 2013.

Lucanids are usually associated with decaying wood and logs in coniferous and deciduous forest habitats. Adults of some species are attracted to lights at night and some feed at sap flows from fluxing trees. Adults of some of the smaller species have been observed feeding on flowers. The eggs are customarily laid in crevices in bark or logs, and the larvae feed on decaying wood and are not economically injurious. The larvae resemble those of Scarabaeidae, but in lucanids the anal opening is longitudinal or Y-shaped, whereas in scarabs it is usually transverse or occasionally Y-shaped. References: Ratcliffe 1991.

Form scarabaeiform (c-shaped, subcylindrical). Color creamy-white or yellowish (except at caudal end which may be darkened by accumulated feces). Cranium heavily sclerotized, lightly pigmented. Antennae 3-4 segmented, last segment greatly reduced in size. Ocelli absent (present in Platycerini, some Sclerostomini, and Ceratognathini). Frontoclypeal suture present. Labrum at apex rounded or weakly lobed. Epipharynx rounded or lobed, with symmetrical tormae. Maxilla with galea and lacinia distinctly separate; maxillary stridulatory teeth absent (present in Platycerus); maxillary palpus 4-segmented. Mandibles elongate, asymmetrical. Abdominal segments 3-7 with 2 annuli, each with 1 or more transverse rows of short setae. Spiracles cribriform. Anal opening Y-shaped or longitudinal, surrounded by 2 fleshy lobes. Legs 4-segmented. Stridulatory apparatus on meso- and metathoracic legs present; claws present. References: Ritcher 1966; Scholtz 1990.

References Cited
BARTOLOZZI, L. 1989. Taxonomic revue of the genus Penichrolucanus Deyrolle 1863 (Coleoptera Lucanidae) with notes on its biology. Tropical Zoology 2: 37-44.

BENESH, B. 1946.
A systematic revision of the Holarctic genus Platycerus Geoffroy. Transactions of the American Entomological Society 72: 139-202.

BENESH, B. 1960. Coleopterorum Catalogus Supplementa, pars 8: Lucanidae. W. Junk, Gravenhage, Netherlands.

BLACKWELDER, R. E. and R. H. ARNETT, JR. 1974. Checklist of the beetles of Canada, United States, Mexico, Central America and the West Indies. Volume 1, Part 3. The scarab beetles, ant-loving beetles, clown beetles, and related groups (red version). The Biological Research Institute of America, Inc., Latham, NY. 120 pp.

BROWNE, D. J. and C. H. SCHOLTZ. 1995.
Phylogeny of the families of the Scarabaeoidea (Coleoptera) based on characters of the hindwing articulation, hindwing base and wing venation. Systematic Entomology 21: 145-173.

CAVENEY, S. 1986. The phylogenetic significance of ommatidium structure in the compound eyes of polyphagan beetles. Canadian Journal of Zoology 64: 1787-1819.

CROWSON, R. A. 1967.
The natural classification of the families of Coleoptera. E.W. Classey, Ltd., Middlesex. 187 pp.

DIDIER, R. and E. SÉGUY. 1953. Catalogue illustré des lucanides du globe. Texte. Encyclopédie Entomologique (series A) 27: 1-223.

FUJITA, H. 2010. The Lucanid beetles of the world / by Hiroshi Fujita ; with the assistance of Tetsuo Mizunuma, Shinji Nagai and Masahiko Suzumura. Mushi-Sha's iconographic series of insects, 6. 472 pp. + 248 plates.

HOFFMAN, C. H. 1937. Biological notes on Pseudolucanus placidus Say, Platycerus quercus Weber and Ceruchus piceus Weber (Lucanidae-Coleoptera). Entomological News 48: 281-284.

HOLLOWAY, B. A. 1960.
Taxonomy and phylogeny in the Lucanidae (Insecta: Coleoptera). Records of the Dominion Museum 3: 321-365.

HOLLOWAY, B. A. 1968. The relationship of Syndesus MacLeay and Sinodendron Schneider (Coleoptera: Lucanidae). New Zealand Journal of Science 11: 264-269.

HOLLOWAY, B. A. 1969. Further studies on generic relationships in Lucanidae (Insecta: Coleoptera) with special reference to the ocular canthus. New Zealand Journal of Science 12: 958-977.

HOLLOWAY, B. A. 1972. The systematic position of the genus Diphyllostoma Fall (Coleoptera: Scarabaeoidea). New Zealand Journal of Science 15: 31-38.

HOWDEN, H. F. 1982. Larval and adult characters of Frickius Germain, its relationship to the Geotrupini, and a phylogeny of some major taxa in the Scarabaeoidea (Insecta: Coleoptera). Canadian Journal of Zoology 10: 2713-2724.

HOWDEN, H. F. and J. F. LAWRENCE. 1974. The New World Aesalinae, with notes on the North American lucanid subfamilies (Coleoptera, Lucanidae). Canadian Journal of Zoology 52: 1505-1510.

IABLOKOFF-KHNZORIAN, S. M. 1977. Über die Phylogenie der Lamellicornia. Entomologische Abhandlungen der Staatlichen Museum für Tierkunde in Dresden 41: 135-200.

KIKUTA, T. 1986.
On the higher taxa of the stag beetle family Lucanidae, pp. 131-138. In: J. Aoki (editor). Papers on Entomology Presented to Professor Takeshiko Nakane in Commemoration of His Retirement. Japanese Society of Coleopterology, Tokyo. 277 pp.

LAWRENCE, J. F. and A. F. NEWTON, JR. 1995. Families and subfamilies of Coleoptera (with selected genera, notes, and references and data on family-group names), pp. 779-1006. In J. Pakaluk and S.A. Slipinski (eds.), Biology, Phylogeny, and Classification of Coleoptera. Papers Celebrating the 80th Birthday of Roy A. Crowson. Muzeum i Instytut Zoologii PAN, Warszawa, Poland.

MAES, J.-M. 1992. Lista de los Lucanidae (Coleoptera) del mundo. Revista Nicaraguense de Entomologia No. 22: 1-121.

MILNE, L. J. 1933. Notes on Pseudolucanus placidus (Say) (Lucanidae, Coleoptera). Canadian Entomologist 65: 106-114.

MIZUNUMA, T. and S. NAGAI. 1994.
The Lucanid Beetles of the World. Mushi-sha, Tokyo. 337 pp.

PAULSEN, M.J. 2013. Annotated checklist of the New World Lucanidae. Online publication Accessed here.

RATCLIFFE, B. C. 1991. The Lucanidae and Passalidae (Insecta: Coleoptera) of Nebraska. Great Plains Research 1: 249-282.

RITCHER, P. O. 1966. White Grubs and Their Allies: A Study of North American Scarabaeioid Larvae. Oregon State University Press, Corvallis, Oregon. 219 pp.

SCHOLTZ, C. H. 1990. Phylogenetic trends in the Scarabaeoidea (Coleoptera). Journal of Natural History 24: 1027-1066.

SCHOLTZ, C. H., D. J. BROWNE and J. KUKALOVA-PECK. 1994. Glaresidae, archaeopteryx of the Scarabaeoidea (Coleoptera). Systematic Entomology 19: 259-277.

SMITH, A.B.T., D.C. HAWKS, and J.M. HERATY. 2006. An overview of the classification and evolution of
the major scarab beetle clades (Coleoptera: Scarabaeoidea) based on preliminary molecular analyses.
Coleopterists Society Monographs 5: 35–46..