Sumitrosis pallescens (Baly)

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 : 35-36

Sumitrosis pallescens (Baly)

( Figs. 82–83 , 152 )

Reared or barcoded specimens. NORTH CAROLINA: Scotland Co., Laurinburg, St. Andrews University , 29.vi.2016, em. by 3.vii.2016, T.S. Feldman , ex Chamaecrista , # CSE 2688 (1 adult, MLBM; 1 pupa, ZFMK) ; OHIO: Adams Co., Lynx, Lynx Prairie , 25.viii.2017, em. 30.viii–4.ix.2017, C.S. Eiseman, ex Chamaecrista , # CSE 4191 (2 adults, ZFMK) ; OKLAHOMA: Payne Co., Mehan , 36.014339° N, - 96.996744° W, 14.vi.2017, em. 24–26.vi.2017, M.W. Palmer, ex Chamaecrista fasciculata , # CSE 3941 (4 adults, ZFMK) .

Hosts. Fabaceae : Chamaecrista fasciculata (Michx.) Greene ; adults also on C. nictitans (L.) Moench ( Cavey 1994). No other hispine has been associated with Chamaecrista , with the exception of Chittenden’s (1902) record of “ Odontota nervosa Panz. ” being reared from C. nictitans . His other records under this name clearly represent a conflation of Sumitrosis inaequalis and S. rosea , and we suspect that the C. nictitans record is referable to S. pallescens .

Biology. The egg is embedded in a pit chewed in the upper leaf surface ( Fig. 82 ), as with Sumitrosis rosea and (sometimes) S. inaequalis . As noted above, S. ancoroides and (sometimes) S. inaequalis deposit their eggs singly in pits chewed in the lower leaf surface. The only other Sumitrosis species in the USA, S. triplehorni Riley , has not yet been associated with any host plant. It therefore now seems safe to say, as suggested by Wheeler & Snook (1986), that Ford & Cavey (1985) were entirely mistaken in listing Sumitrosis among the genera whose “eggs are laid in clusters of 3–7 on a leaf or leaflet.”

The leaf mines of Sumitrosis pallescens have not been described previously, beyond this statement by Cavey (1994): “Mines were observed to usually occur in pairs, one each on adjacent leaflets. The larger mine of a pair houses the pupa.” In our limited experience, each larva mines several leaflets, but these are not always adjacent or in pairs. Furthermore, we have seen examples of the leaflet containing the egg being almost entirely mined out, and of the pupa occupying a mine little more than twice its size ( Figs. 82–83 ). As with S. ancoroides , the mine is flat and largely confined to the upper leaf surface. The larva establishes secondary mines by chewing a slit in the upper epidermis in the basal half of the leaflet, then working its way toward the apex. Frass is in scattered, minute particles, 1–5 times as long as wide.

Notes. Both Ohio and Oklahoma are new state records for Sumitrosis pallescens . Our barcoded specimens all belong to BIN BOLD:AAU7048.

Figures

FIGURES 78–86. Leaf mines of Sumitrosis spp.; 78: S. ancoroides on Strophostyles helvola (with pupa at center); 79: S. inaequalis on Eurybia divaricata (with egg at upper right, and larva above center); 80: S. inaequalis on Eutrochium maculatum; 81: S. inaequalis on Symphyotrichum anomalum (with pupa at upper right); 82: S. pallescens on Chamaecrista sp. (with egg above center); 83: same (secondary mines, with pupa at upper right); 84: S. rosea on Celastrus orbiculatus (with egg at right); 85: S. rosea on Laportea canadensis (with larva left of center); 86: S. rosea on Coursetia cf. caribaea (larva in secondary mine).

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.