Siricidae, Billberg, 1820

John M. Leavengood, Jr. & Smith, Trevor Randall, 2013, The Siricidae (Hymenoptera: Symphyta) of Florida, Insecta Mundi 2013 (309), pp. 1-16 : 3-4

Key to the Adult Siricidae of Florida

Below is a dichotomous key to the known Siricidae of Florida and S. noctilio . The only North American genus not represented in the key is Xeris , which is distinguished by having only one apical metatibial spur and at least 22 antennal segments. Specimens of S. behrensii (Cresson 1880) emerged from imported wood in Florida ( Smith and Schiff 2002). However, this species is not considered to be among the Florida fauna since the authors are not aware of any natural collection records. For specimens collected outside of Florida, refer to the revision of the New World Siricidae by Schiff et al. (2012).

1.

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Both sexes with two apical metatibial spurs ( Fig. 1 ); antennae with 18 or more segments, often exceeding 22 segments .................................................................................................................. 2 Both sexes with only one apical metatibial spur ( Fig. 2 ); antennae with fewer than 22 segments

........................................................................................................................................................ 3 2(1).

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Both sexes often with a large white spot behind each eye ( Fig. 3 ); female cornus long and slender, basally constricted ( Fig. 4 ); forewing with crossvein Cu 1 absent ( Fig. 30, 31 ); male metatarsus slender, with the 1 st segment at least 4 times as long as it is broad, commonly up to 5-6 times longer, and 2 nd and 3 rd segments at least 2 times as long as they are broad ............... .................................................................................................................................. 4 ( Urocerus )

Both sexes with head entirely black ( Fig. 5 ); female cornus short and triangular ( Fig. 6 ), without a basal constriction (except slightly in S. longicauda ); forewing with at least basal half of Cu 1 present ( Fig. 16, 19 , 24 ); male metatarsus stout and laterally flattened, with the 1 st segment no more than 4 times as long as it is broad, and 2 nd and 3 rd segments triangular and as long or longer than broad ( Fig. 20 , 26 ) ........................................................................ 7 ( Sirex )

3(1).

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Both sexes with antennae having 14-15 segments; body without long golden hairs ( Fig. 10-13 ) ..................................................................................................... Tremex columba (Linnaeus)

Both sexes with antennae having 20-21 segments; body with long golden hairs ( Fig. 7-9 ) ....... .................................................................................... Eriotremex formosanus (Matsumura)

4(2).

— Ovipositor and cornus present ( Fig. 4, 6 ) (female) ...................................................................... 5 Ovipositor and cornus absent ( Fig. 10 , 20 , 25 ) (male) ................................................................ 6 5(4).

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Abdomen mostly reddish-orange, sometimes with basal and/or apical segments blackish ( Fig. 28-

30) .................................................................................................... Urocerus cressoni Norton Abdomen black, but cornus orangish ( Fig. 31-32 ) ...................... Urocerus taxodii (Ashmead)

6(4).

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Figures

Figures 1-6. 1) Apical metatibial spur, female Sirex noctilio. 2) Apical metatibial spur, male Tremex columba. 3) Head of female Urocerus taxodii. 4) Cornus of female U. cressoni. 5) Head of female S. areolatus. 6) Cornus of female S. areolatus.

Figures 28-32. Urocerus species. 28) Lateral habitus, female U. cressoni. 29) Dorsolateral habitus, female U. cressoni. 30) Wings of male U. cressoni. 31) Wings of male U. taxodii. 32) Dorsolateral habitus, female U. taxodii.

Figures 14-21. 14-16) Sirex areolatus female. 14) Lateral habitus. 15) Dorsolateral habitus. 16) Wings. 17-19) Sirex nigricornis female. 17) Lateral habitus. 18) Dorsolateral habitus. 19) Wings. 20-21) Sirex nigricornis male. 20) Dorsal habitus. 21) Lateral habitus.

Figures 22-27. 22-24) Sirex noctilio female. 22) dorsal habitus. 23) Lateral habitus. 24) Wings. 25-27) Sirex noctilio male. 25) Dorsal habitus. 26) Lateral habitus. 27) Wings.

Figures 7-13. 7-9) Eriotremex formosanus female. 7) Dorsal habitus. 8) Wings. 9) Lateral habitus. 10-13) Tremex columba. 10) Dorsal habitus, male. 11) Lateral habitus, male. 12) Lateral habitus, female. 13) Wings, female.