Octotoma marginicollis Horn

Eiseman, Charles S., Feldman, Tracy S. & Palmer, Michael W., 2024, New larval host records, parasitoid records, and DNA barcoding data for North American leaf-mining leaf beetles (Coleoptera: Chrysomeloidea), Zootaxa 5549 (1), pp. 1-60 : 26

Octotoma marginicollis Horn

( Fig. 142 )

Collected specimens. ARIZONA: Cochise Co., Cave Creek Canyon Nature Trail , 31.887942, 109.172708, 4.viii.2023, C.S. & A.B. Eiseman & J.A. Blyth, feeding on Fraxinus velutina , # CSE8358 (1 adult, MLBM); 31.888069, -109.171444, 4.viii.2023, C.S. & A.B. Eiseman & J.A. Blyth, feeding on Ageratina herbacea , # CSE8359 (1 adult, MLBM) .

Hosts. Asteraceae : Acourtia thurberi (A.Gray) Reveal & R.M.King ( Jones & Brisley 1925) . Eiseman (2014) found adults feeding on Brickellia betonicifolia A.Gray in association with leaf mines, but the identity of the miner was not confirmed. We can now add Ageratina herbacea (A.Gray) R.M.King & H.Rob. to the list of asteraceous plants on which adults have been found feeding, which also include Aldama cordifolia (A.Gray) E.E.Schill. & Panero , Baccharis bigelovii A.Gray , B. glutinosa Pers. , B. salicina Torr. & A.Gray , Brickellia californica (Torr. & A.Gray) A.Gray , and B. floribunda A.Gray ( Clark et al. 2004; Staines 2015). As with several other Asteraceaefeeding leafminers (Eiseman 2022), including Sumitrosis inaequalis (Weber) (see below), this species is also associated with plants in the order Lamiales , at least as adults, which have been found abundantly on Lamiaceae ( Monarda fistulosa var. menthifolia (Graham) Fernald ) and Oleaceae ( Fraxinus greggii A.Gray , F. velutina Torr. ) ( Clark et al. 2004).

Biology. Jones & Brisley (1925) noted that Acourtia leaves are often completely mined out by several larvae whose mines have become confluent, but they provided no further details. The mines found in association with adults on Brickellia betonicifolia contained one to four larvae and were full-depth with frass in fairly sparse, compact pellets 1–2 times as long as wide ( Eiseman 2014). Adults window-feed in elongate patches on the upper surfaces of leaves.

Figures

FIGURES 142–161. Chrysomelidae adults; 142: Octotoma marginicollis; 143: O. plicatula; 144: Odontota dorsalis; 145: O. floridana; 146: O. horni; 147: O. scapularis; 148: Stenopodius cf. lateralis; 149: Sumitrosis ancoroides (reared from Stylosanthes biflora); 150: S. ancoroides (reared from Strophostyles helvola); 151: S. inaequalis; 152: S. pallescens; 153: S. rosea (reared from Hylodesmum glutinosum); 154: S. rosea (reared from Laportea canadensis); 155: S. rosea (another individual reared from same collection of L. canadensis leaves); 156: S. rosea (reared from Celastrus orbiculatus); 157: Oulema palustris; 158: Altica cf. lazulina; 159: Dibolia borealis; 160: D. chelones; 161: D. melampyri.