Zoosphaerium taitii Anilkumar & Wesener, 2020

Wesener, Thomas & Anilkumar, Pooja Avinipully, 2020, The millipedes collected by the Museum " La Specola " on Madagascar 1989 / 1991, with the description of three new species of giant pill-millipedes (Diplopoda, Sphaerotheriida, Arthrosphaeridae), ZooKeys 930, pp. 3-35 : 3

Zoosphaerium taitii Anilkumar & Wesener sp. nov. Figures 5C , 8 , 9 , 10

Etymology.

Adjective, the species is named after the land isopod expert Dr. Stefano Taiti who collected this species.

Material examined.

1 ♂ Holotype (MZUF), Madagascar: SW 17 km Edi Sakaraha, forêt de Zombitsy, foresta secca, 22°52'47.1"S, 44°36'41.1"E, n. Mag. 1107. Legit: Bartolozzi, S. Taiti, C. Raharimina, 15 May 1991.

Other material.

1 ♂, CAS BLF Mei-99 Ma-14, Province Toliara, Zombitse Nature Reserve, 16 km E Sakaraha, 825 m, tropical forest on sand, 22.88231°S, 44.70062°E, coll. E. L. Schlinger, M. E. Irwin, 15-18 Dec 1999.

Diagnosis.

Zoosphaerium taitii sp. nov. is mostly similar to Z. isalo , both differing from all other species in the anterior telopod where sclerotized teeth are absent on the third podomere. Zoosphaerium taitii sp. nov. differs from Z. isalo in the shorter marginal bristles of the endotergum (protruding above the tergite margin in Z. isalo ), the higher number of ventral spines on leg 2 (four or five versus six or seven) and the slightly differently shaped anal shield (tapering in Z. isalo , well-rounded in Z. taitii sp. nov.).

Description

(all measurements in mm):

Body length: holotype male: length 20.4, width 9.4 (2nd) up to 9.9 (tergite 9 = widest), height 5.4 (2nd = highest).

Coloration: Strongly faded due to exposure to alcohol. Antennae dark green. Legs basally brown and apically green. Head and collum light green. Tergites and anal shield faded light brown.

Head: Eyes with 60-70 ommatidia. Antennae short, protruding up to leg 3 or 4. Size of antennomeres 1>2<3>4<5<6 (Fig. 8A ). Antennomeres 1-3 with sclerotized teeth. Antennomeres 1 and 6 with a single row of sensilla basiconica (Fig. 8B, C ). Antennomeres 3-6 with long setae. Antennomere 6 with an apical disc containing four apical sensory cones (Fig. 8B ).

Gnathochilarium: Stipites and central mentum with long setae, setae absent at center of lamellae linguales. Inner palpi protruding to medial side of gnathochilarium, bearing single field of sensory cones. Rudimentary lateral palpi sharing a well-developed base bearing four sensory cones. Hypopharynx with one row of marginal teeth. Central pads apically protruding from lamellae linguales, with a median triangular incision on each pad. Posterior half of underside with single field of large sensory cones interspersed with longer, slimmer structures.

Mandible not dissected.

Stigmatic plates: First stigmatic plate apically elliptical with marginal setae, lateral end pointed (Fig. 9A ). Second stigmatic plate trapezoidal with nine spines near tracheal opening, covered with tiny setae inside and few long marginal setae (Fig. 9B ).

Pleurite: First pleurite weakly extending posteriorly with a well-rounded tip.

Collum: Glabrous, anterior and posterior margin with sparse rows of isolated setae.

Thoracic shield: Glabrous expect for narrow lateral grooves.

Tergites: Surface glabrous and shiny, chagrined. Paratergite tips not projecting.

Endotergum: Inner area with narrow conical spines, very few isolated setae. A single row of rounded-elliptical cuticular impressions. Broad smooth marginal ridge. Two rows of marginal bristle protruding towards marginal brim, few reaching tip, other few reaching 1/4-3/4 of distance to margin (Fig. 5C ).

Anal shield: Large and well rounded, surface glabrous. Two locking carinae, second carina 2.3 times longer than first, close to anal shield margin.

Legs: Leg 1 with four or five spines, leg 2 with six or seven spines, leg 3 with seven or eight ventral spines and an apical spine, legs 4-21 with nine ventral spines and one apical spine. In leg 9 femur 2.0, tarsus 4.7 times longer than wide. Uniform distribution of setae on all podomeres. Prefemur and femur with few long setae. Femur ridge length reaching 1/4 of femur length (Fig. 9C ).

Female unknown.

Male sexual characters: Gonopore slightly oval, rounded apically, divided, reaching 1/2 length and 1/4 width of coxa, covered by 1/4 semicircular membranous plate apically and 3/4 sclerotized plate basally with few setae (Fig. 9B ).

Anterior telopod: Harp carrying one stridulation rib positioned medially with one end pointing laterad. Podomere 1 broad with marginal setae, few setae above stridulation rib (Fig. 9D ) and a shallow mesal cavity laterally (Fig. 9E ). Podomere 2, process visible in anterior view, reaching 2/3rd of length of podomere 3 (Fig. 9D ), with sclerotized nubs along apical-mesal margin and one basal spine present below field of spots (Fig. 9F ). Podomere 3 apically broad, rounded, longer than podomere 2 (Figs 9F , 10G ), and carrying one dark sclerotized spot at apical tip (Fig. 9F ). Field of sclerotized spots run along apical-basal margin with four spines out of six visible (Figs 9F , 10G ). Three spines positioned at apical margin above field of spots, one in middle of cavity with tip protruding to sclerotized spot, one small single spine in lateral projected area slightly towards base, and one spine at base of field of spots (Fig. 10G ). Podomeres 2 and 3 covered with setae except mesally (Fig. 10G ).

Posterior telopod: Movable finger 2.5 times longer than wide with tip slightly curving towards immovable finger. Apical tip with a dark sclerotized spot, eight sclerotized crenulated teeth (arranged in three groups), three mesal spines (two merged at tip), with very few setae at base and a shallow mesal cavity with two membranous lobes (Fig. 10H, I ). First five teeth positioned below apically merged spines, other two teeth below middle spine, located in middle of first membranous lobe, two isolated single tooth located between both membranous lobes (Fig. 10H ). Immovable finger 4.3 times longer than wide, reaching 3/4th of length of movable finger, slender, tip curved towards movable finger with a row of small sclerotized spots along 1/4 apical mesal margin, covered with setae in posterior aspect (Fig. 10H ). Podomere 1 glabrous except for very few marginal setae.

Remarks.

This species was described as a population of Z. isalo in a previous study, already with a remark that the status of the population should be evaluated when more male specimens become available ( Wesener 2009). With the additional male specimen available from the collections of the "La Specola" Museum, we feel more confident in describing the Zombitse specimens as a species separate from Z. isalo . The species lives in sympatry with Z. album Wesener, 2009, a species belonging to a different species group ( Wesener 2016).

Figures

Figure 5. SEM, Endotergum of mid body tergites, ventral view. A Zoosphaerium mangabe sp. nov., male from Marojejy B Zoosphaerium bartolozzii sp. nov., male holotype C Zoosphaerium taitii sp. nov., male holotype. Abbreviations: IA = inner area; ci = cuticular impressions; mr = marginal ridge; mb = marginal bristles.

Figure 8. Zoosphaerium taitii sp. nov., male holotype, SEM, Right antenna. A lateral view B antennomeres 1 and 2 with sclerotized teeth C apical disc with four sensory cones. Abbreviations: ac = apical cone; ad = apical disc; sb = sensilla basiconica; sc-t = sclerotized teeth.

Figure 9. Zoosphaerium taitii sp. nov., male holotype. A, B Coxae of first and second right legs, D - F Left anterior telopod. A first stigmatic plate B second stigmatic plate C 9 th left leg D anterior view E posterior view F mesal view. Abbreviations: as = apical spine; cx = coxa; ds-p = dark sclerotized spot; fe = femur; f-rdg = femur ridge; gp = gonopore; mem-p = apical membranous part of plate covering gonopore; pf = prefemur; po = postfemur; scl-p = sclerotized plate; sp-p = second podomere process; sr = stridulation rib; ss = sclerotized spot; st = stigmatic plate; syn = syncoxite; ta = tarsus; ti = tibia; to = tracheal opening. Scale bars: 1 mm.

Figure 10. Zoosphaerium taitii sp. nov., male holotype, left anterior telopod. G lateral view. H, I Left posterior telopod. H posterior view I anterior view. Abbreviations: cr-t = crenulated teeth; ds-p = dark sclerotized spot; imm-f = immovable finger; mf = movable finger; ml = membranous lobes; s-ca = shallow cavity sn = sclerotized nubs; ss = sclerotized spot. Scale bars: 1 mm.