Brachoria cedra, KEETON, 1959

Marek, Paul E., 2010, A revision of the Appalachian millipede genus Brachoria Chamberlin, 1939 (Polydesmida: Xystodesmidae: Apheloriini), Zoological Journal of the Linnean Society 159 (4), pp. 817-889 : 836-837

BRACHORIA CEDRA KEETON, 1959

‘THE CEDAR GLADE MIMIC MILLIPEDE’ ( FIG. 8A–D,

FIG. 39K–M; SUPPORTING INFORMATION VIDEO S1)

Brachoria cedra Keeton, 1959: 17 . Keeton, 1965: 85; Hoffman, 1971: 233.

Diagnosis: Adult males of B. cedra are distinct from other Brachoria species based on the combination of: Size. Body length on average smaller than other species (♂ 37.49, ♀ 38.68). Colour. Three-spotted, yellow metatergal spots, paranotal spots, anterior and posterior collum spots, legs (Fig. 39K). Exoskeleton. Caudolateral corners, paranota 1–4 slightly rounded, lateral margins angled cephalically. Gonopods. Gonopodal acropodite narrow, half width of tibia on leg pair 9, of uniform width throughout. Prefemur with thin, sharp prefemoral process. Acropodite curved medially in D-shaped form ( Fig. 8D ). Arc immediately distal beyond cingulum slightly elbowed. Acropodal apex projecting laterally. Acropodite distal to postcingular arc bent 90°, with curved acuminate apex ( Fig. 8D , arrow).

Variation: Brachoria cedra is known from three areas in Wise, Norton City, and Lee Counties (6♂ and 4♀ represent specimens throughout this range). There is some variation in coloration amongst these specimens with an orange variant (Fig. 39M) of the common three-spotted morph and a two-spotted yellow morph (Fig. 39L), both of which are less common than the three-spotted yellow morph. Measurements: ♂ (N = 6) BL = 33.56–40.78 (37.49/2.69). CW = 6.85–7.70 (7.34/0.33). IW = 4.60–5.09 (4.85/0.17). ISW = 1.28– 1.60 (1.45/0.12). B10W = 9.10–10.49 (9.92/0.58). B10H = 5.55–6.25 (5.93/0.28). ♀ (N = 4) BL = 37.76– 39.92 (38.68/0.93). CW = 7.10–7.72 (7.28/0.29). IW = 5.29–5.60 (5.42/0.13). ISW = 1.67–1.81 (1.74/ 0.06). B10W = 9.71–11.00 (10.21/0.59). B10H = 6.66– 7.57 (7.06/0.38).

Description: Male described by Keeton (1959).

Ecology: Brachoria cedra was previously only known from the cedar glades around Jonesville in Lee County; however, I found a disjunct population around High Knob in the tulip and maple deciduous forests there, and later in other localities in Lee County. All specimens were collected during the day in either cedar forests ( Juniperus virginiana L.) or mixed mesophytic deciduous forests. At the cedar glade localities, individuals were found beneath layers of decomposing cedar leaves. Brachoria cedra normally occurred beneath cedar duff on the plate-like dolomitic limestone. One other xystodesmid encountered sympatrically at this locality is A. v. corrugata , which has a strong mimetic resemblance to B. cedra . At the other localities, B. cedra was found beneath decomposing leaves of broadleaf species like maple, tulip, and oak. Note: individuals of B. cedra may easily be confused in the field with A. v. corrugata , B. dentata , B. insolita , B. mendota , B. sheari , and B. hoffmani because of similarity in colour patterns (around High Knob all of these species, except B. sheari and B. mendota , can be found as mimics), but can be distinguished from the other Brachoria by the diagnostic characters and from A. v. corrugata by the presence of the following characters (viewed with a 20¥ loupe): Acropodite with midlength transverse groove, cingulum. Arc immediately distal beyond cingulum slightly elbowed. Acropodite not circular like in A. v. corrugata .

Distribution: Known from four areas in south-western Virginia from Edd’s Mill in south-western Lee County, north-east through the cedar glades and Lovelady Gap, to the highlands around High Knob in Norton City and Wise Counties. Brachoria cedra co-occurs with B. dentata , B. insolita , B. mendota , B. sheari , and B. hoffmani forming a component of a Müllerian mimicry ring with them.

Material examined: Type specimens. ♂ holotype ( USNM) from Lee County, Virginia, cedar glades near Jonesville , v.1955 (coll: L. Carr) (vidi). Nontype specimens. Virginia : 1♂ (SPC000276*: DQ 490680 ) , Lee County, The Cedars , CR656, 1.6 rd km south US 58, telephone line clearcut (36.66032°N, - 83.18390°W, 408 m), 28.v.2004, 10:45 (coll: P. Marek) ; 1♀ ( MMC0277 ) , Lee County, The Cedars , CR-738 (36.65624°N, - 83.20165°W, 436 m), 28.ix.2006, 16:00 (colls: P. and B. Marek) ; 1♂ ( MMC0280 ) , 1♀ ( MMC0277 ) , Lee County, Lovelady Gap, CR 619 (36.763661°N, - 82.88194°W, 815 m), 27.ix.2006, 12:15 (coll: P. and B. Marek) ; 1♂ ( PMLN00027 ) , Lee County, west of Long Hollow School (36.725600°N, - 83.05930°W), 30.v.1990 (coll: J. Fulks) ; 1♂ ( MMC0349 ) , 1♀ ( MMC0338 ) , Lee County, Edd’s Mill (36.63098°N, - 83.35825°W, 395 m), 29.ix.2006, 15:00 (coll: P. Marek) ; 1♂ (SPC000273), Wise County, Stone Mountain, near Eagle Knob , FR238, east of curve in road (36.895321°N, - 82.60513°W, 777 m), 27.v.2004, 19:30 (coll: P. Marek) ; 1♂ ( MMC0029 ) , 1♀ ( MMC0024 ) Wise County, Osborn Rock, FR 238 (36.894991°N, - 82.59027°W, 1145 m), 17.viii.2006, 9:00 (colls: P. Marek and C. Spruill) .

Figures

Figure 8. Brachoria cedra Keeton, 1959. A–D, holotype specimen gonopods: A, left male gonopod, anterior view; B, left male acropodal apex, ventrolateral view; C, left male gonopod, medial; D. same, posterior (acropodite length = 1.59 mm).