Glomeridesmidae Latzel, 1884

Iniesta, Luiz Felipe Moretti, Ferreira, Rodrigo Lopes & Wesener, Thomas, 2012, The first troglobitic Glomeridesmus from Brazil, and a template for a modern taxonomic description of Glomeridesmida (Diplopoda), Zootaxa 3550, pp. 26-42 : 29

Family Glomeridesmidae Latzel, 1884

Zephroniodesmidae Cook, 1895: 2

Comment: A monogeneric family ( Jeekel 2003, Shear 2011).

Characters: Females with 36 pair of legs, 20 tergites plus anal shield; males with 35 leg pairs, 19 tergites plus anal shield (see Hoffman 1982, Enghoff et al. 1993). Males with 20 tergites and 37 leg pairs are supposed to exist but have not yet been discovered ( Carl 1942).

Head without ocelli, but with large, circular organ of Tömösváry ( Fig. 3 D). Genae (head sclerites below the antennae) absent. Antennae long, slender, with seven joints and an apical disc carrying four long, slender apical cones ( Fig. 3 F). The mandible seems to consist of a sutureless fused cardo and stipites ( Fig. 3 C), confirming earlier observations ( Carl 1942).

Each body segment composed of tergite forming a semicircle, one large laterotergite ('pleurite') on each side, and two coxosternites with stigma and tracheal apodeme ( Fig. 3 A, 4A, B). As in earlier papers on the phylogeny of Pentazonia (Wesener & VandenSpiegel 2009), we follow here Snodgrass’ view of the so-called pleurites as laterotergites ( Snodgrass 1958). Tergites generally soft, weakly calcified, not divided into pro-, meso- and metazona, but with numerous (5–10) longitudinal striae ( Fig. 6 A, B, E). Lateral tips of last 3–5 tergites always(?) projecting posteriorly, overlapping following tergites with a sharp-edged tip ( Fig. 6 A, B). Ozopores for secretion of defense fluid absent.

Development hemianamorphic, leg and tergite development apparently decoupled ( Enghoff et al. 1993). Last leg pair of males (either 33rd, 34th or 35th) modified to telopods ( Fig. 8 A, B, 9A, B). Last leg in females, as well as second last in males, characteristically modified, with undivided large sternal plate ( Fig. 7 A), tarsus posteriorly protruding above anal shield ( Fig. 7 B). Starting at the mid-body each odd-numbered coxa (e.g. 11, 13, 15) with eversible coxal pouch ( Fig. 4 A, C).

Gonopores in both sexes located on posterior side of coxa 2. Females with long ovipositors (misinterpreted as 'penes' by earlier authors) forming long (up to half of body length), eversible, membranous tubes ( Fig. 3 B). Male gonopore consisting of two small sclerotized plates located mesally on the coxa ( Fig. 5 A, B).

Telopods (only known from 7 species) divided into a syncoxite with inner horns ( Fig. 8 A) and a 4-jointed telopod. Joint 2 at apico-mesal margin with a species-specific (?) membranous field, joint 3 elongated into immovable finger located laterally (see Wesener & VandenSpiegel 2009: fig. 37) or posteriorly ( Fig. 9 A) of joint 4, which forms the movable finger and carries a prominent apical spine ( Fig. 9 A, B, D).

The complete inner morphology remains unstudied (see discussion below).

Figures

FIGURE 3. G. s p e l a e u s n. sp., paratype female (ISLA 3837), SEM. A: midbody segment, anterior (oral) view; B: coxosternites and prefemur of 2 nd leg with ovipositor, posterior view; C: head, ventral view; D: right organ of Tömösváry, lateral view; E: head, dorsal view; F: antenna, antennomere 7 and disc, lateral view; G: gnathochilarium, underside. Abbreviations: C & P = tarsal claw and paranychium; Ca = cardines of gnathochilarium; Ca 1 = cardo, basal mandible joint 1; Ca 2? = either cardo (joint 1) or stipites (joint 2) of mandible; cP = central pads, modified central palpi; Cx-St = coxosternite; F = femur; Gn = gnathochilarium; iP = inner palpi; La = labrum; LL = lamella linguales; LP = lateral palpi; LT = latero-tergite; Me = mentum; O = ovipositor; Pl = plate covering organ of TO; poF = postfemur; prF = prefemur; St = stipes of gnathochilarium; sc = apical cones; St? = sternite?; T = tergite; Ta = tarsus; Ti = Tibia; TO = organ of Tömösváry; roman numerals refer to number of antennomeres. Scale bars: A = 200 µm; B = 100 µm; C = 200 µm; D = 20 µm; E = 200 µm; F = 20 µm; G = 100 µm.

FIGURE 6. G. spelaeus n. sp., paratype male (ZFMK Myr 0936), SEM, midbody tergite. A: dorsal view; B: lateral view; C: sclerotized knob with setae; D: posterior margin, ' limbus'; E: anterior margin. Abbreviations: ant = anterior; s = (sensorial) seta; str = stria; arrow points to oral side. Scale bars: A = 500 µm; B = 100 µm; C = 10 µm; D = 100 µm; E = 200 µm.

FIGURE 8. G. s p e l a e u s n. sp., paratype males, SEM, telopod, anterior view. A: left telopod with syncoxite and inner horns (ZFMK Myr 0936); B: right telopod, podomeres 2 – 4, (ISLA 3838); C: right telopod, podomere 2, detail of swollen membranous area (ZFMK Myr 0936). Abbreviations: IH = inner horns; mem = membranous area; roman numerals refer to podomere number. Scale bars: A = 300 µm; B = 30 µm; C = 50 µm.

FIGURE 7. G. s p e l a e u s n. sp., paratype male (ZFMK Myr 0936), SEM. A: last pair of walking legs (34) in oral view with sternite and subanal plate; B: anal shield, dorsal view, line marks part covered by last tergite (19). Abbreviations: Cx-St? = coxosternite; F = femur; poF = postfemur; prF = prefemur; s = field of small setae; S = isolated long setae, sp = spine-like claw; St = sternite; sub = subanal plate. Scale bars = 200 µm.

FIGURE 4. G. s p e l a e u s n. sp., A – D paratype male (ZFMK Myr 0936), E paratype female (ISLA 3838) SEM. A: leg pairs 4 – 7 with latero-tergites; B: coxosternite 6 with stigma opening; C: coxal pouch 7; D: midbody latero-tergite of male; E: endbody latero-tergite female. Abbreviations: cp = coxal pouch; Cx-St = coxosternite; F = femur; LT = latero-tergite; poF = postfemur; prF = prefemur; st = stigma; Ta = tarsus; Ti = Tibia; numbers refer to leg pair number. Scale bars: A = 500 µm; B = 80 µm; C = 30 µm; D = 100 µm; E = 100 µm.

FIGURE 5. G. spelaeus n. sp., paratype male (ZFMK Myr 0936), SEM. A: right male leg 2, posterior view; B: gonopore; C: tarsus 2 with tarsal claw, apical spine and paranychium; D: midbody tergite, underside; E: detail of anterior margin of underside; F: detail of posterior margin of underside, ' endotergum'. Abbreviations: Apo = tracheal apodeme; Cx-St = coxosternite; F = femur; Go = gonopore; Par = paranychium; poF = postfemur; prF = prefemur; Ta = tarsus; Ti = Tibia. Scale bars: A = 300 µm; B = 30 µm; C = 60 µm; D = 200 µm; E = 20 µm; F = 8 µm.

FIGURE 9. G. s p e l a e u s n. sp., paratype males, SEM, telopod, posterior view. A: right telopod, podomeres 2 – 4 (ZFMK Myr 0936); B: left telopod, podomeres 2 – 4 (ISLA 3838); C: right telopod, podomere 2, detail of swollen membranous area (ZFMK Myr 0936); D: right telopod, detail of podomere 3 & 4 (ZFMK Myr 0936). Abbreviations: mem = membranous area; pro = process of podomere 3; roman numerals refer to podomere number. Scale bars: A = 100 µm; B = 100 µm; C = 20 µm; D = 40 µm.