Bothriothorax Ratzeburg 1844

Zuparko, Robert L., 2015, Annotated Checklist of California Encyrtidae (Hymenoptera), Zootaxa 4017 (1), pp. 1-126 : 16

Bothriothorax Ratzeburg 1844

Hosts. Diptera : Syrphidae

californicus Howard 1895a: 609

Type. USNM

Distribution. C (Alameda, Alpine, Contra Costa, Fresno, Humboldt, Lassen, Marin, Mendocino, Merced, Mono/Tuolumne border, Monterey, Nevada, Riverside, Sacramento, San Francisco, San Luis Obispo, San Mateo, Santa Clara, Santa Cruz, Sierra, Solano, Sonoma, Tehama, Trinity, Yolo, coastal southern California)

Host/habitat. Eupeodes nitens , Scaeva pyrastri , Syrphus opinator

Remarks. Howard described B. californicus from three specimens, noting the “ types ” were in the U.S. National Museum, but I found only two specimens there. The Nearctic Bothriothorax species are badly in need of revision—the only generic treatment was by Howard (1895a) and there are discrepancies between the specimens and the descriptions therein. This species may prove to be a senior synonym of B. faridi and B. rotundiformis (q. v.).

faridi Kamal 1926: 283

Type. USNM

Distribution. C (Santa Clara)

Host/habitat. Syrphus opinator

Remarks. In the original description, Kamal did not provide a diagnosis for this species. It is very close to B. californicus , and the only difference I could discern between the types of the two species is a pair of medial longitudinal carina on the propodeum of B. faridi (missing in B. californicus ). However, this is not a reliable defining characteristic, as an examination of a series of specimens from Merced County show it is present in some specimens and absent from others, so I suspect B. faridi will prove to be a junior synonym of B. californicus .

nigripes Howard 1895a: 610

Type. USNM

Distribution. N (Colusa, Contra Costa, Imperial, Inyo, Kern, Los Angeles, Marin, Mono, Monterey, Orange, Placer, Riverside, Sacramento, San Bernardino, San Diego, San Joaquin, San Mateo, Santa Barbara, Trinity, Tulare )

Host/habitat. Eupeodes lapponicus , E. volucris

Remarks. In the original description, Howard erroneously reported the first funicle segment was as long as the pedicel. There is a series of specimens of this species from Los Angeles County that were apparently reared from the pupa of a Lycaenidae (Lepidoptera) (EMEC). Interestingly, this is not the first record of a Bothriothorax associated with Lepidoptera— B. altensteinii Ratzeburg 1844 has been reported as a hyperparasitoid of Lymantria dispar (Linnaeus) ( Lepidoptera : Lymantriidae ) via Exorista larvarum (Linnaeus) ( Diptera : Tachinidae ) ( Erdös 1957), and B. paradoxus ( Dalman 1820) has been reported from L. dispar , as well as Phalera bucephala (Linnaeus) (Notodontidae) , and as a hyperparasitoid of Gastropacha quercifolia (Linnaeus) (Lasiocampidae) , via the tachinids Compsilura concinnata (Meigen) , E. larvarum and Sturmia scutellata (Robineau-Desvoidy) ( Gyorfi 1942) . Although Noyes (2001) considers the P. bucephala record erroneous based on the discontinuity in the generic host range (predatory syrphids vs. parasitic tachinids), a similar dichotomy is present in the genus Syrphophagus , which are known as primary parasitoids of syrphids and hyperparasitoids of aphids.

rotundiformis Howard 1895a: 610

Type. USNM

Distribution. N (Placer)

Host/habitat. Unknown

Remarks. This species is known from only the single type specimen, which is very close to B. californicus . I am treating it as a good species, but further research may prove these two species to be synonymous.

spp.

Remarks. Specimens that appear to represent three additional species were collected in Alameda, Marin, Nevada, San Mateo and Santa Clara, Santa Cruz and Sonoma counties (CAS, EMEC, LACM, RLZC).