Apheloria whiteheadi ( Shelley, 1986 )

Apheloria whiteheadi ( Shelley, 1986) View in CoL

Vernacular name: “The Laurel Creek millipede”

Figs 17, 18

Sigmoria (Sigiria) whiteheadi Shelley, 1986: 102 View in CoL .

Detailed taxonomic history in Appendix 1.

Material examined: Type specimens— ♂ holotype ( VMNH), 1 ♂, 2 ♀ paratypes ( VMNH) from Virginia, Patrick County , along Laurel Creek on Blue Ridge Parkway at mile 174.3, 20 May 1983, 16:00 (Colls: R. Hoffman). ( vidi). ( 1 paratype collected by R. Hoffman from same locality on 23 June 1984.) Non type material examined in Appendix 2. Material examined are archived in the Virginia Tech Data Repository at: https://doi.org/10.7294/29829209

Diagnosis: Apheloria whiteheadi is distinct from other apheloriine species based on the following combination of characters: Color. Tergites with yellow stripes and legs ( Fig. 17). ♂ Gonopods. Gonopodal acropodite ρ-shaped ( Fig. 18A)—not uniformly circular as in other Apheloria species nor smoothly oval-shaped as in Rudiloria . Acropodite apex flange-like and abruptly twisted ( Fig. 18B)—not of uniform width throughout as in other Apheloria species. Acropodite shaft without cingulum nor preapical teeth nor projections as in Appalachioria , Brachoria . Prefemur with a short, blunt prefemoral process located marginally ( Fig. 18B, pfp)—not long, scythe-like as in other Apheloria species nor located medially ( Figs 4B, 7B, 8B, 9B, 13B, pfp). Acropodite not bent 90° posteroventrally at prefemur ( Fig. 17B), prostatic groove generally straight from cannula to acropodite base, without bend tubercle nor acute angle on corner of bend ( Figs 4B, 7B, 13B, bt).

Note about coloration: The anterior and posterior metatergal stripes of the collum meet at the paranota and appear as a continuous yellow ring around the collum’s periphery.

Variation. There is a single color morph of A. whiteheadi : striped, with yellow metatergal—paranotal stripes, anterior collum stripe, and legs ( Fig. 17).

There is typical sexual size dimorphism between males and females, where females are larger, and negligible variation of measurements within individuals of the same sex. Somatic measurements: ♂ (n = 2) BL = 40.53–40.78 (40.66/0.18). CW = 5.54–5.59 (5.57/0.04). IW = 3.65–3.77 (3.71/0.08). ISW = 1.01–1.05 (1.03/0.03). B10W = 6.89–6.91 (6.90/0.01). ♀ (n = 10) BL = 31.42–45.96 (38.71/5.32). CW = 5.59–6.59 (5.89/0.30). IW = 3.89–4.48 (4.17/0.18). ISW = 1.06–1.22 (1.13/0.06). B10W = 7.09–8.39 (7.59/0.36).

Ecology. Apheloria whiteheadi individuals were typically encountered in rhododendron cove forests ( Means and Marek, 2017). More seldom were they found in montane mixed oak forest ( Means et al. 2021c). Syntopic tree species recorded with A. whiteheadi included oak, maple, tulip poplar, witch hazel, pine, beech, paper birch, and sweet gum.

Due to potential mimicry in color and overlap in distribution, A. whiteheadi may be confused in the field with A. corrugata , A. virginiensis , and P. flavipes . Apheloria whiteheadi can be distinguished from these taxa by its distinctive gonopod morphology, specifically by its ρ-shaped acropodite ( Fig. 18A), which is not uniformly circular as in other Apheloria species, nor sublinear in shape, with an acicular prefemoral process as in P. flavipes . Pleuroloma flavipes also possesses a distinctive claw-like bifurcated acropodite composed of a tibial process and a solenomere ( Shelley, 1980).

Distribution. Apheloria whiteheadi has the smallest distributional area of the genus, and is known from Floyd and Patrick counties in Virginia ( Fig. 11). The species is listed as a threatened species in Virginia and is afforded protection by state law.