During a survey of Corynorhinus rafinesquii Lesson, 1827 in southeastern Georgia, USA, chiggers (larval Trombiculidae) and other mites were removed from their wings and ears. Among these collections, we identified an unnamed species of the trombiculine genus Hoffmanniella. This is the first record of the genus from the United States.

Hoffmanniella solickiana Crossley and Clement, n. sp

Description. (Terminology of Goff et al. 1982)

Idiosoma—Holotype 520 × 370 μm engorged. Eyes 2/2, anterior larger, on indistinct ocular plate. 28 plumose dorsal setae arranged 2-8-6-6-4-2, length 45–72 μm. 22 plumose ventral setae, 2-2-6-6-4-2, length 22–35 μm. Total idiosomal setae 50.

Gnathosoma—Palpal setal formula N/N/NNN/5BS (Fig. 1A); galeal seta branched. Palpal claw three-pronged. Cheliceral base with scattered punctae, blade 40 μm with tricuspid cap. Gnathobase with paired branched setae.

View Figure

• Download as Powerpoint
• Download Figure

Scutum (Fig. 1B)—Scattered punctae on anterior two-thirds. Anterior margin straight, posterior margin slightly convex, lateral margins concave. Scutal setae plumose; sensillae with numerous fine branches. Scutal measurements (holotype) in micrometers: AW 67, PW 78, AP 28, SB 31, AM 50, AL 35, PL 60, SENS 85.

Legs (Fig. 1C–E)—Seven-segmented, with terminal claw and claw-like empodium. Leg I measurements (holotype) 245 μm; leg II, 200 μm; leg III, 210 μm. All legs bearing feathered setae; setal bases indicated on figures. Leg I with one genuala; two tibialae and one microtibiala; two tarsalae, one microtarsala, and one pretarsala. Leg II with one genuala, two tibialae, two tarsalae, and one pretarsala. Leg III with one genuala and one tibiala.

Material Examined

Etymology

The species is named for Donald Solick, who first introduced me to bats and who remains a true friend (M.J.C.).

Taxonomic Remarks

All three known Hoffmanniella species are parasitic on bats. Vercammen-Grandjean (1960) created the genus Hoffmanniella for Trombicula beltrani Hoffmann, 1946, a parasite of Lasiurus blossevillii (Lesson & Garnot) (syn. Nycteris borealis mexicana [Saussure]) collected in the Mexican state of Puebla. Later, Goff (1988) added H. transylvanica parasitic on a vampire bat, Desmodus rotundus (Geoffroy), from Costa Rica. Hoffmanniella solickiana is, thus, the third species known for the genus and the first from the continental United States. It is readily separated from the other two by the pattern of specialized setae on the legs. According to Brennan and Goff (1977), H. beltrani has a papilliform microgenuala I, a seta missing in H. solickiana. Hoffmanniella transylvanica has three genualae I versus a single genuala I in H. solickiana. Further, the sensillae of H. transylvanica have fewer than a dozen prominent branches; sensillae of H. solickiana have >20 shorter branches. The three species also differ in numbers of idiosomal setae. Hoffmann (1949) illustrates numerous ventral setae on H. beltrani. Hoffmanniella transylvanica has 54 total idiosomal setae, whereas H. solickiana has but 50.

Biological Remarks

All collection sites were in bottomland hardwood forests along river floodplains. Collection occurred in low-lying areas supporting flood-adapted tree species, especially Nyssa aquatica L. and Taxodium distichum L. The host, C. rafinesquii, roosts inside large, hollow cavities that readily form in these tree species (Clement and Castleberry 2013). Concurrent surveys in additional counties in southern Georgia (Bleckley, Calhoun, Dougherty, Glynn, Pulaski, and Screven) did not yield any H. solickiana. Corynorhinus rafinesquii have rarely been inspected for ectoparasites, but individuals captured in Tennessee yielded specimens of Macronyssus crosbyi Radovsky (Mesostigmata: Macronyssidae; Reeves et al. 2007). Additional references to C. rafinesquii or Plecotus rafinesquii in the ectoparasite literature appear to be synonyms for C. townsendii Cooper, 1837.