Notes on the psyllid fauna of Texas and their host plants
Psyllid diversity in a region is correlated with the plant diversity in that region, and so one would assume that Texas, a state second only to California in floral diversity, would also be home to a large number of psyllid species. But while California leads the US with over 150 psyllid species, only about 30 psyllids are known from Texas.
One reason for this could be that plant genera such as Salix, Ceanothia, & Cercocarpus, which serve as hosts for a great many psyllid species, are most diverse west of Texas, and indeed known psyllid diversity increases from east to west in the US following these plants and others. So while a state like Alaska only has 30% of the vascular plant diversity of Texas, more psyllid species are reported from that state, largely in part due to three times as many Salix species occurring in Alaska than in Texas.
But another factor is that the psyllid fauna of states like Alaska, California, and other western states has been more extensively studied than the fauna of Texas. Furthermore, the psyllid fauna surrounding many of the state's largest cities in central or eastern Texas can probably be expected to differ slightly from the psyllid fauna of the southwestern parts of the state. I believe that as the state is more thoroughly studied, more psyllid species will be found there.
Following is a list of host plants and the psyllids associated with them that have been reported from Texas. Plants with an asterisk * denote hosts for which associated psyllids have not yet been photographed.
Western TX
Suaeda nigra - Craspedolepta suaedae (host mostly restricted to western TX e. to Del Rio. Look for abundant white cottony wax on plant)*Rhus virens - Leurolophus vittatus (host e. to Austin)
Senegalia greggii - Aphalaroida pithecolobia
*Vachellia rigidula - Aphalaroida acaciae (host s. TX nw to Del Rio)
Salix exigua - Cacopsylla alba (host e. to Del Rio)
Celtis pallida - Leuronota maculata (host s. TX nw to Del Rio)
Baccharis spp. (salicina, salicifolia, pteroniodes) - Calinda spp.
Eastern TX inc. Austin
Ilex vomitoria - Gyropsylla ilecis (host from e. TX w. to around Austin. Look for leaf galls)Citrus sp. - Diaphorina citri (introduced sp.)
Diospyros spp - Baeoalitriozus diospyri
Rhus copallinum - Calophya nigripennis
Widespread hosts
*Rumex sp. - Aphalara rumicisSolidago sp. - Craspedolepta spp.
Celtis sp. - Pachypsylla celtidisgemma (look for bud galls), P. celtidismamma & P. celtidisasterisca & P. celtidisvesicula (leaf galls), P. celtidisinteneris (twig galls), P. venusta (petiole galls), Tetragonocephala flava (lerps on leaves). Note that adults of the leaf galling species cannot be ID'd from photos alone in this region, but the galls are distinct.
Prosopis sp. - Aphalaoida inermis, Heteropsylla texana. Note that P. glandulosa is the dominant Prosopis in TX
*Vachelia farnesiana - Heteropsylla mimosae
Amorpha fruticosa - Amorphicola amorphae
Ratibida columnifera, Rudbeckia (hirta?) - Bactericera antennata (look for galls on leaves)
Salix nigra, S. goodinggii - Bactericera minuta
Solanaceae spp. - Bactericera cockerelli
Some potential plants worth checking:
Rhus spp. are host plants for many psyllids in the genus Calophya throughout the US, but strangely no Calophya have been reported in the literature from Texas. However, they most definitely do occur in the state, as proven by this observation. Rhus aromatica is a widespread host with a lot of psyllid potential, and several other Rhus spp. are also probably worth checking.Dermatophyllum (=Sophora) secundiflorum - a nymph was observed on this host in Austin - this may represent a new species.
Mimosa sp. - John Schneider found Heteropsylla huasachae on an unspecified Mimosa sp. near Houston. That species is also known from a number of other Mimosoid legumes.
Fabaceae in general - Purely speculative on my part, but I suspect that Mimosoid and Caesalpinioid legumes, especially near the sourthern border of the state, may be hosts for a number of unreported species.
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Very interesting biogeographical pattern. What if you tally regional psyllid diversity as the number of host plant families used? Could argue that's another measure of evolutionary diversity within the group. Might be less influenced by important host plant families.
California would definitely still lead in terms of host family diversity but states like Alaska would certainly fall considerably, since many of the species there are associated with Salicaceae / Betulaceae. Throughout much of the US though the same host family trends can be found: Asteraceae, Anacardiaceae, Rosaceae, & Salicaceae are some of the big ones, with Rhamnaceae and Ericaceae becoming more common in the west, Betulaceae at more northern latitudes and Fabaceae becoming increasingly more common in the southwest (+Florida). Texas is interesting in that it represents a western limit for many typically eastern species but also has a large southwestern component characterized by a relatively high Fabaceae-host diversity
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