Sumitrosis rosea (Weber)

Eiseman, Charles S., 2014, New Host Records and Other Notes on North American Leaf-Mining Chrysomelidae (Coleoptera), The Coleopterists Bulletin 68 (3), pp. 351-359 : 357

Sumitrosis rosea (Weber)

This species mines leaves of various plants of the pea family ( Fabaceae ), and Staines (2006, 2012) makes no mention of Celastrus L. ( Celastraceae ) or Laportea Gaud. (Urticaceae) as larval, adult, or incidental hosts of any hispine species. Specialists disagree about whether beetles reared from these hosts may belong to separate, cryptic species (C. L. Staines and S. M. Clark, in litt.), and it appears that further work is needed before conclusions can be drawn. The record of S. rosea being reared from Chenopodium album L. ( Amaranthaceae ) in Indiana ( Butte 1969) may also be worthy of further investigation. Ford and Cavey (1985) regard this as likely a case of misidentified host plant, but it is difficult to imagine any of the known hosts of this beetle being mistaken for that species.

Hicks (1944) reported that Anoplitis inaequalis (Weber) , a synonym of S. inaequalis , was “a very common leaf miner of Celastrus scandens ” L. in Ontario. Later ( Hicks 1965), this species-level identification was reconsidered: “Another Anoplitis sp. that is poorly known in the United States... and Canada mined the leaves of climbing bittersweet, Celastrus scandens L., in southern Ontario where populations were observed for several years at Windsor, De Cew Falls, and Niagara-on-the-Lake. The host is common to the northeast into the Ottawa District but the distribution of the insect appears to be limited. The author was never able to find adults of this species in the District but four dead pupae, one in each of four mined leaves, were found at Britannia Bay in Ottawa.” These are apparently the only published records of Celastrus as a host for Sumitrosis ( Clark et al. 2004) .

In Massachusetts, the native C. scandens is now rare, but the exotic Celastrus orbiculatus Thunb. is abundant ( Anonymous 2012). On 3 July 2013, I found a very small blotch mine in a C. orbiculatus leaf in Pelham, Massachusetts, beginning with an oval egg inserted in a pit chewed in the upper leaf surface. On 22 July, I determined that the miner was dead, and I opened the mine to reveal a somewhat moldy adult Sumitrosis (specimen in MLBM). On 13 September in Northampton, Massachusetts, I found a more or less complete mine in the same host; it was a full-depth blotch with short strips of frass throughout ( Fig. 14 ). The adult emerged on 22 September, feeding in small, elongate patches on either side of the leaf, 2–3 mm long by 1 mm wide. The completed mines of the two beetles covered about 6 cm 2 and 5 cm 2. Both of these beetles were unambiguously S. rosea , not S. inaequalis , based on present species concepts, and it seems likely that the Ontario bittersweet miners are conspecific.

Hicks (1965) was also the first to report miners in Laportea canadensis (L.) Weddell. He referred to them as Anoplitis philemon (Newman) and observed them over several years in southern Ontario. Since then, Riley and Enns (1979) reported adults collected on this plant in Missouri; Ford and Cavey (1985) examined one or more larvae from “ Urticaceae ” (no indication of genus) in northern Virginia; and McPheron (1985) reared Laportea miners in Illinois. Wheeler and Snook (1986) mentioned seeing a hispine developing on Laportea without reference to location, although most of their observations took place in Pennsylvania. They stated: “Although the forms reared from various legumes and wood nettle may indeed be conspecific, it is unusual for a North American hispine to mine the leaves in such distantly related families.”

From mines in Laportea canadensis , I collected a larva in southeastern Ohio on 13 September 2012 and a pupa in western Iowa on 17 September 2012. Both have been deposited in the USNM so that they can be compared with immature stages of S. rosea from other hosts. These records, in addition to my second discovery of a mine in Celastrus , are unusual in terms of season as well as host. McPheron (1985) observed adults ovipositing in mid-May and their offspring emerging as adults five weeks later; he did not observe a later generation. Wheeler and Snook (1986) stated that S. rosea appears to be univoltine but reported finding eggs as late as July and suggested that a second generation might be possible in some years.

Figures

Figs. 13–17. 13) Young Sumitrosis inaequalis larva mining in white wood aster (Eurybia divaricata) leaf; egg at upper right; 14) Mine of Sumitrosis rosea in leaf of Oriental bittersweet (Celastrus orbiculatus); 15) Detail of presumed Dibolia chelones mine in leaf of white turtlehead (Chelone glabra), showing squiggly strings of frass; 16) Leaf of climbing false buckwheat (Fallopia scandens) mined by four Mantura floridana larvae; 17) Mines of Monoxia angularis in Atriplex prostrata leaf.