Mimuloria castanea ( McNeill 1887 )

Hennen, Derek A. & Shelley, Rowland M., 2015, A contribution on the milliped tribe Nannariini (Polydesmida: Xystodesmidae): Revalidation of Mimuloria Chamberlin 1928; identities of Fontaria oblonga C. L. Koch 1847, and Nannaria minor Chamberlin 1918; elucidation of the tribal range; and commentaries on Nannaria Chamberlin 1918, and Oenomaea Hoffman 1964, Insecta Mundi 2015 (418), pp. 1-21 : 6-9

Mimuloria castanea ( McNeill 1887)

Fig. 3 , 9–14 .

Polydesmus castaneus McNeill 1887: 329 , fig. 8.

Fontaria castanea (not Williams and Hefner 1928: 106, fig. 9b): Bollman 1893: 123.

Mimuloria castanea: Chamberlin 1928: 153 . Causey 1952: 8, fig. 6c; 1955: 30. Chamberlin and Hoffman 1958: 37.

Nannaria castanea: Chamberlin 1928: 153 ; 1949: 4. Hoffman 1999: 365–366. Marek et al. 2014: 36.

Castanaria castanea: Causey 1950b: 1 .

Castanaria depalmai Causey 1950b: 1–3 , fig. 1. New synonymy.

Mimuloria depalmai: Causey 1952: 9 . Chamberlin and Hoffman 1958: 37–38.

Nannaria depalmai: Hoffman 1999: 366 . Marek et al. 2014: 36.

Type specimens. Male holotype and one female paratype ( NMNH) collected on an unknown date prior to 1887 in Bloomington, Monroe Co., Indiana, probably by Jerome McNeill.

Diagnosis. Acropodite arching strongly and broadly mediad; inner projection from prefemoral process relatively short, acuminate, and variably falcate, extending for 1/8 of acropodital length.

Color in life. According to Causey (1950 b, 1952), individuals from Barry Co., Missouri, had reddishorange paranota and a “black-brown” dorsum. Recently molted females that DAH collected in Carroll Co., Arkansas, evidenced by the black middorsal haemolymph vessels’ being partly visible through the tegument, displayed light pinkish-orange paranota with broad, concolorous bands along the anterior margins of the collums against light olive-green base colors that were darker along the anterior halves of the metaterga than on the caudal halves ( Fig. 3 ).

Description (derived from the fragmented holotype and intact topotypes [FSCA]). Holotype length ~ 23 mm; segmental widths as follows: collum ~ 3.7 mm, segment 2 ~4.0 mm, 5 ~ 4.1 mm, 12 ~ 4.2 mm (maximal width); W/L ratio 18.3%. Facial setae lost in some individuals but sockets visible: epicranial 0–0, interantennal 1–1, frontal 1–1, genal 0–0, clypeal 2–2, labral 14–14. Antennae reaching back to middle of 4 th tergite, ~ 4.3 mm long; 1 st antennomere slightly ovoid, 2–6 clavate, 7 truncated and cy- lindrical, with four terminal sensory cones within setose rim; antennomeres 2–5 sparsely setose, 6–7 denser; relative lengths of antennomeres 6>3>2=4=5>1>7.

Dorsum smooth, polished ( Fig. 3 ). Collum ~ 1.1 mm long, sides slightly elevated, corners rounded. Caudal paranotal margins slanting upwards or dorsad, overlapping anterior margins of succeeding paranota, caudolateral corners becoming progressively more extended and triangular from 15 th paranota caudad. Ozopores opening laterad, positioned centrally in midbody peritremata and more caudally in posterior ones. Epiproct subtriangular, slanting downward or ventrad, with two submarginal setae on each side and six apical ones arising from spinnerets. Paraprocts smooth, margins rimmed. Hypoproct semilunar, with one submarginal seta per side.

Sides of metaterga with noticeable grooves dorsad and shallow ones ventrad. Strictures narrow. Spiracles ovoid, oriented along lengthwise body axis, margins not elevated, clearly separated from coxae, anterior segmental spiracles larger than posterior ones. Postgonopodal sterna smooth and glabrous except for two small tubercles between 9 th legs (caudal legs on segment 7). Legs generally long and slender, present on segments 2–18; 1 st legs short, 2 nd legs slightly crassate with long, subcylindrical gonapophyses extending caudad from coxae, vasa deferentia opening apically. Prefemoral spines long, acuminate, overhanging femora and extending for 1/3 of postfemoral lengths, relative lengths of podomeres 3>6>2>5=1=4. Coxae hirsute proximal to midlengths, setae of succeeding podomeres becoming progressively denser distad. Tarsal claws on legs 2–9 (on segments 3–7) spatulate but not twisted.

Gonopodal aperture ovoid, sides and caudal margin elevated. Gonopods in situ with acropodites arching broadly mediad, extending well beyond segmental midwidth, overlapping opposite member near midlength, arch projecting over caudal half of 6 th sternum. Gonopod structure as follows ( Fig. 9–13 ): Prefemoral process short or nubbin-like with short, slender, falcate projection arising from inner corner. Acropodite tapering for most of length, expanding apically with short, narrow, lobes opposing each other on dorsal/ventral surfaces and caudally directed, triangular, and apically rounded lamina arising between them on inner surface. Prostatic groove arising in pit in prefemur, extending along acropodital stem onto terminal triangular lamina.

Cyphopodal aperture oblong, narrow. Cyphopod ( Fig. 14 ) small, positioned just inside aperture; valves located lateral to receptacle, caudal valve slightly larger, surfaces without noticeable hairs; receptacle proportionally large, subtriangular, subequal in size to both valves combined, with three long hairs arising anteriolaterad; operculum not evident.

Variation. Causey (1955) surmised that the prefemoral process “may be expected to show some variation when the species is better known,” and indeed this is true. The basal structure may be triangular or subrhomboid and vary in size from short, inconspicuous, and nubbin-like to larger and distinct. Additionally, the length and degree of curvature of the inner projection vary from short and strongly falcate to longer and gently curved ( Fig. 9, 10 ). Though sclerotized, they are so thin, fine, and even acicular, particularly when falcate, as to resemble macrosetae on initial viewing; they are fragile and would seem to be easily broken, which would leave an unadorned structure like that in M. missouriensis . The acropodital lobes in the males from Tennessee are narrower and less distinct, and the terminal lamina is less clearly demarcated from the stem.

Ecology. The species inhabits oak-hickory woodlands in Arkansas and Missouri ( Causey 1950a).

Distribution ( Fig. 2 ). Northeastern Indiana and western Tennessee to southwestern Missouri and northwestern Arkansas, a distance of approximately 792 km (495 mi). Grant Co., Indiana, is the northern- and easternmost record; Henderson Co., Tennessee, is the southernmost; and Carroll Co., Arkansas, and Barry Co., Missouri, are the westernmost.

Published records. General range statement. Ozark region ( Chamberlin and Hoffman 1958).

Arkansas: Arkansas in general ( Causey 1955). Carroll Co., Lake Leatherwood and 0.3 km (0.2 mi) S of it ( Causey 1950b, Chamberlin and Hoffman 1958, Hoffman 1999, Marek et al. 2014).

Indiana: Indiana in general ( Chamberlin and Hoffman 1958). Southern Indiana in general ( Chamberlin and Hoffman 1958). Grant Co., erroneously assigned to N. terricola by Causey (1952) and

Chamberlin and Hoffman (1958). Monroe Co. ( Causey 1950b), Bloomington ( McNeill 1887; Causey 1952, 1955; Chamberlin and Hoffman 1958; Hoffman 1999; Marek et al. 2014).

Missouri: Barry Co., Mark Twain National Forest ( Causey 1952). St. Louis Co. ( Causey 1955). Wayne Co., Patterson, Holmes Cave, erroneously assigned to M. missouriensis by Causey (1952).

New samples (in all accounts, samples based solely on females are assigned geographically).

Arkansas: Searcy Co., 8 km (5 mi) S Mull (in Marion Co.), M, 22 March 2011, M. B. Connior (NCSM). Stone Co., Blanchard Springs, 2F, 18 May 1973, D. H. Kavanaugh, H. Goulet (NMNH). Indiana: Monroe Co., Bloomington, MM, FF, juvs., C. H. Bollman (NMNH), and M, F, R. W. Siegel (FSCA). Missouri: Dent Co., along Dry Fork Cr., F, 28 August 1964, H, Exline (FSCA). Jefferson Co., 3.2 km (2 mi) SE Pacific, M, 3 November 1935, and M, 3 November 1936, L. Hubricht (NMNH) New State Record. Wright Co., Norwood, F, 22 May 1966, W. E. LaBerge (NMNH). Tennessee: Henderson Co., Natchez Trace State Park, Fern Nature Trail, 3M, 4F, 26 May 1980, R. M. Shelley (NCSM) New State Record.

Remarks. Causey (1952) and Chamberlin and Hoffman (1958) erroneously assigned the Grant Co., Indiana, record to N. terricola Williams and Hefner 1928 , then in Mimuloria . We examined this sample, and it actually is M. castanea ; likewise, we examined the sample from Wayne Co., Missouri, and found it to be M. castanea , not M. missouriensis as Causey (1952) reported.

We emphasize that Mimuloria castanea is not the same species as, and should not be confused with, Fontaria castanea Williams and Hefner 1928 , for which Loomis and Hoffman (1948) proposed Nannaria ohionis . Loomis and Hoffman (1948), Chamberlin and Hoffman (1958), and Hoffman (1999) have cited castanea from both Ohio in general and southern Ohio, but neither it nor Mimuloria as we define the taxon is presently known from this state.

Figures

Figure 2. Distribution of Mimuloria (colored symbols) with peripheral tribal records (black and green stars). Dots, castanea group. Red, M. castanea; green, M. missouriensis; blue, M. davidcauseyi. Diamonds, dilatata group. Solid orange, M. d. dilatata; open orange, M. dilatata sigmoidea; pink, M. rhysodesmoides; violet question mark, Mimuloria sp. The course of the Missouri River across Missouri is shown in light blue.

Figures 3–8. The castanea group, somatic and in situ features. 3) M. castanea, dorsal views of two recently molted females from Carroll Co., Arkansas. 4–8) M. davidcauseyi male from Newton Co., Arkansas. 4) Left side of three midbody tergites, dorsal view. 5) Head, antennae, and segments 1–7, anterior and subventral views, respectively. 6) Midbody sterna and basal podomeres, ventral view. 7) Gonopods in situ, ventral view. al, anterior sternal lobe; cl, caudal sternal lobe. 8) Pregonopodal tarsal claws, ventral view.

Figures 9–17. The castanea group, genitalic features. 9–14) M. castanea. 9) Telopodite of left gonopod of holotype, ventral view. 10) Prefemoral process of variant with long inner branch, ventral view. 11–13) Distal extremities of acropodital variants in medial, dorsomedial, and dorsal views, respectively. 14) Left cyphopod of female paratype, subventral view. 15) M. missouriensis holotype, telopodite of left gonopod, ventral view. 16–17) M. davidcauseyi holotype. 16) Telopodite of left gonopod, ventral view. 17) The same submedial view. dl, dorsal apical lobe; pfp, prefemoral process; r, receptacle; tl, terminal triangular lamina; v, valve; vl, ventral apical lobe.