Petralycus caryapecaus McDaniel & Bolen 1983
Creators: name: Uusitalo, Matti
Publisher: name: Zenodo
Year: 2025
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Sarcoptiformes
Alycidae
Petralycus
Petralycus caryapecaus

description: Petralycus caryapecaus McDaniel & Bolen, 1983
(Fig. 47A–K)
Petralycus caryapecaus McDaniel & Bolen, 1983: 814, figs. 3–4; Uusitalo 2010: 76.
Redescription. Dorsum (n= 1 female, Fig. 47A, B, K). Length 222 µm; holotrichous number of plumose dorsal setae, slightly larger in caudal segments; naso ca. 9 µm, narrow and rounded at tip, 3 pairs of ciliate prodorsal setae (vi, sce, in), setae exp and eyes absent, sensilla sci filiform with short cilia, sensilla ve rounded, all inserted on hard integument.
Venter (Figs. 47J; McDaniel & Bolen 1983: fig. 4a, c). Ventral side neotrichous with small stellate setae; 12 genital setae per valve; 4 anal setae per valve.
Gnathosoma (Fig. 47G, H). 3 pairs of plumose and elongated setae on subcapitulum; chelicerae chelate-dentate, robust, and elongated without cheliceral setae; large palpal solenidion reaching over two apical eupathidia, tactile setae elongated.
Legs (Fig. 47C–F). Pedal setae ciliate and elongated; 18 foot-shaped eupathidia ventrodistally on tarsus I; solenidial formula for tarsi, tibiae, genua and femora on legs I, II, III and IV, respectively: 1-1-0-0, 3-2-1-1, 6-2-1-2, 3-3-0-0+0; famulus I placed abaxially, near distal end of tarsus I.
Material examined. 1 female as Petralycus caryapecaus from sandy soil, Moorei Creek, National Battleground, Penden Co., North Carolina, USA, 23 December 1988, Eric G. Bolen, slide TAMU-ENTO X1646472 at the Texas A&M University Insect Collection, Department of Entomology. The examined specimen labelled as Petralycus caryapecaus by B. McDaniel was in very poor condition, shrunken and with an air bubble inside; therefore, the redescription is based on the original description (McDaniel & Bolen 1983).
Differential diagnosis. The naso of P. caryapecaus is ca. half the size of the naso of P. celtisacinus. The solenidial pattern is unique as shown in the table above. The American species P. celtisacinus and P. obtusicornis have chelicerae with a seta but the chelicerae of P. caryapecaus and the European P. unicornis are bald. All four have a holotrichous setal pattern while the African P. longicornis and P. brevicornis are neotrichous. The naso is blunt-tipped in the American species and P. longicornis but with a sharp point in P. unicornis and P. brevicornis.
Remarks. According to McDaniel & Bolen (1983): “The holotype specimen of P. caryapecaus will be deposited with National Museum of Natural History, Washington, D.C.”—but the specimen is not in their database (Dr. Debra Creel, in litt.). The holotype was collected in San Patricio Co., Texas, a riparian woodland known as Pecan Motte with features virtually identical with those for Hackberry Motte. The mixed tree stands, among other things with hackberry (Celtis) and pecan (Carya), obviously inspired the naming of both American species.
The original figures of P. celtisacinus and P. caryapecaus (McDaniel & Bolen, 1983, figs. 1–4) are distorted, without scale bars and the observations and measurements based on the figures are not quite reliable. The total length 222 µm given for P. caryapecaus in the text was measured in fig. 47B from the nasal tip to caudal end and used in adjusting the scale bars for the fragments of the figure. The solenidial pattern of P. celtisacinus in the original description corresponded with the examined material, and the solenidiotaxy of P. caryapecaus is also reliable. However, a sceptical attitude is advisable in regards to minor character states, such as absence of barbs on sensillus ve (as mentioned in text on p. 814, but present in fig. 3f = 47A), absence of a cheliceral seta, and absence of a pointed rutellum, until fresh material is available and examined.
description: Published as part of Uusitalo, Matti, 2025, A review of the family Alycidae (Acari, Acariformes) from North America, pp. 1-92 in Zootaxa 5602 (1) on page 79, DOI: 10.11646/zootaxa.5602.1.1