Allozercon leytensis, Klompen & Gerdeman, 2023

Klompen, Hans & Gerdeman, Beverly S., 2023, Genus-level revision of the Heterozerconoidea (Parasitiformes: Mesostigmata), Zootaxa 5322 (1), pp. 1-66 : 37-40

Allozercon leytensis new species

( Figs 18–19 , 39–40 , 69–70 , 85 , 95 )

Diagnosis. Anterior dorsal body margin in both adults with multiple medium to long setae; antero-marginal area of dorsal shield in males with small, hook-like spines; sternal lyrifissures iv 3 in male absent.

Description. Female idiosoma length 1530 (152), width 1287 (186) (N=5); male idiosoma length 1311 (73), width 1058 (32) (N= 5). Complete measurements in Tables 3–4.

Chelicera ( Figs 18–19 ). Basal part of fixed digit in female stout, length width ratio 1–2. Movable digit in adults with thin, straplike dorsal extensions. Movable digit in female elongate, digit length>6 times basal width. Inside movable digit female with brush-like structure. Excrescences on male chelicera interdigital. Spermatodactyl on fixed digit of male chelicera, of the straight type.

Palp. Axial outgrowth of palp trochanter in female distinct and membranous. Seta v 2 in female poorly developed, setal base barely visible. Axial outgrowth of palp trochanter in male distinct and sclerotized, solid. Seta pd1 on femur present. Setae on femur long, thick spines. Seta al2 on genu absent, seta pl present. Number of sensilla on palp tarsus 12. Formula: 2–6–5–14–12.

Gnathosoma ( Figs 39–40 ). Gnathotectum of female without prominent points. Anterior margin gnathotectum not serrate. Overall shape of gnathotectum curved. Lateral lips enlarged to form a trough; posterior extension of the trough long, extending distinctly past insertions of setae hyp2. Distance between setae hyp3 and sc subequal to that between hyp3 and hyp2. Setae hyp2 at least twice as long as hyp3. Cornicula membranous, without distal notch. Additional setal base-like structure on hypostome present.

Dorsum ( Figs 48–50 ). Dorsal shield in older females not fully covering the dorsum, shield in recently molted females and in males covering entire dorsum. Peritrematal shield may be adjacent to dorsal shield but never fused to it. Anterior dorsal margin of idiosoma in both sexes with multiple medium to long setae, inserted anterior to the dorsal shield in females, on the shield in males (average number female 8 (1); male 7 (3)). Antero-marginal area of dorsal shield in males with small, hook-like spines (average number 31 (2)). Median dorsal setae minute. Posterior dorsal setae Z2–Z4 minute.

Sternal area female ( Fig. 69 ). Areas near insertion sternal setae st1 sclerotized, forming isolated platelets. Sclerites of sternal setae st1 and st2 not fused. Sternal setae st1 and lyrifissures iv1 inserted on the same shield. Areas near insertion sternal setae st2 sclerotized, forming isolated platelets. Areas near insertion sternal setae st3 sclerotized, fused to genitiventral shield or on isolated platelets close to genitiventral shield. Metasternal setae st4 absent. Areas near insertion sternal setae st5 sclerotized, fused to genitiventral shield. Sternal lyrifissures iv 1 in adults present. Sternal lyrifissures iv3 absent. Distinct curved, sclerotized ridge on anterior margin of genital shield absent.

Sternal area male ( Fig. 70 ). Areas near insertion sternal setae st1 sclerotized, fused to endopodal shield. Sternal setae st1 and lyrifissures iv1 inserted on same shield. Sclerotized areas near insertion sternal setae st2 fused to endopodal shield. Sclerotized areas of sternal setae st2 and st3 not fused. Areas near insertion sternal setae st3 sclerotized, fused to sternitiventral shield or on isolated platelets adjacent to sternitiventral shield. Sclerotized areas near insertion sternal setae st5 fused with sternitiventral shield. Sternal lyrifissures iv3 absent. Genital opening presternal. Genital shield overlaying base of the tritosternum. Sternitiventral area smooth.

Opisthogaster ( Figs 69–70 ). Metapodal and sternitiventral shields in male not fused. Posterolateral margin of metapodal shields in adults rounded. Setae Zv 3 in adults absent. Opisthogastral suckers in adults present, posterior to ventral shield, heterozerconid type. Apodemes extending from opisthogastral suckers present, small but distinct knobs in posterior position (both sexes). Ventral shield area with a single shield. Sternitiventral and anal shields in male fused, but line of fusion still visible. Setae Sv2 and Sv3 inserted on the genitiventral (female) or sternitiventral (male) shields. Additional seta(e) present in unsclerotized area between metapodal and ventrigenital shields. Setae Jv5 inserted posterior to ventrianal fusion line. Insertion paranal setae (pa) posterior to the anus. Postanal (po) seta of similar length as paranal (pa) setae. Setae Z 5 in male elongate, setae S5 medium in length. Marginal opisthosomal setae small, setiform. Lyrifissures iv5 inserted near anterior margin of the suckers. Postero-marginal shields in both sexes wide, extending lateral well beyond opisthogastral suckers.

Legs ( Figs 85 , 95 ). Tibiae and tarsi of legs I somewhat narrowed relative to the rest of the leg. Acrotarsus on legs I present. Femora I setae ad3 and pl2 present, setae v3 and v4 absent. Genua I setae ad3 and pd3 absent. Tibiae I seta ad2 present, setae ad3, av2 and pv2 absent. Femora II setae av2 and pv2 absent. Genua II–IV setae ad3 and pl2 absent. Genua II setae pd3 absent, genua III–IV seta pd3 present. Tibiae II–IV setae ad2, pd3 and pl2 absent. Femora III seta v3 absent. Tarsi IV setae av4 and pv4 absent. Complete chaetotaxy in Table 2. Coxae I setae in male setiform. Femora I setae al1 and al 2 in male spinose, in anteroventral position. Femora I seta av in male large, straight spine. Femora II seta al in male setiform. Femora II seta pl in male spine and ventral in position. Femora II setae av and pv in male spines. Genua II seta pv and tibiae II seta pv in male spines, barely half as long as setae av; in female setiform and as long as av. Tarsi II seta pl 1 in both sexes setiform. Trochanters III in male: seta al spine-like, setae av and pl setiform.

Type depositories: Holotype male at UPLB , accession number UPLB MNH ACA-01335. Paratypes at UPLB and OSAL

Material examined. Philippines, Leyte Prov., Leyte Is., VISCA, Hubasan Creek, 10.7731 N 124.8109 E, 7–Jun- 2000, Gerdeman, Beverly S. & Garcia, Rufino C., ex millipede, BSG 00–0607–45, 1 male, holotype, UPLB MNH ACA-01335. Same data, 1 female, OSAL 053240 ; 1F, OSAL 053241 ; same locality, date and collectors, ex big black millipede, BSG 00–0607–13,14,15,16, 1 female, OSAL 0053242 ; same data , 1 female, OSAL 053243 ; 1 male, OSAL 053244 ; ex big black female millipede, BSG 00–0607–19–21, 1 female, OSAL 053245 ; 1 female, OSAL 053246 ; 1 female, OSAL 053247 ; 1 male, OSAL 053248 ; ex big brown male millipede, BSG 00–0607–41, 1 female, OSAL 053249 ; ex litter, 1 male, OSAL053250 ; 1 female, OSAL 053251 ; Philippines, Southern Leyte Prov., Leyte Is., Silago , 10.5333 N 125.1178 E, 16–Jun-2000, Gerdeman, Beverly S., Garcia, Rufino C., ex litter, BSG 00–0616–1, 1 female, OSAL 053184 ; same locality, date and collectors, ex black female millipede, BSG 00–0616–12, 1 male, OSAL 053185 ; 1 male, OSAL 106780 .

Etymology. Named after the island on which the specimens were recovered.

Remarks. Allozercon leytensis differs from both Al. audax and Al. fecundissimus by the presence of a set of distinct setae on the anterior margin of the body and from Al. elapsus (= audax ) by much shorter setae Z5.

Specimens of Al. leytensis occasionally co-occurred with specimens of Al. ( Philippinozercon ) sp. on the same millipede hosts. Co-occurrence of multiple species of Heterozerconidae on a single host individual was previously reported for Afroheterozercon species in Central African Republic and Gabon ( Klompen et al. 2013) and, as noted earlier, for Amyzozercon and Ecuazercon on polydesmids in Ecuador.

Figures

FIGURES 16–19. Heterozerconidae, chelicera males, photograph (top) and composite drawing (bottom): 16–17, Allozercon ex Mindoro (OSAL 053284); 18–19, Allozercon leytensis n. sp. (OSAL 053250).

FIGURES 39–42. Heterozerconidae, gnathosoma, adults: 39, Allozercon leytensis n. sp., female (OSAL 053243); 40, Allozercon leytensis n. sp., male (UPLB MNH ACA-01335; red arrow: sclerotized axial extension of palp trochanter); 41, Al. (Philippinozercon) makilingensis, female (OSAL 053271); 42, Al. (Philippinozercon) makilingensis male (OSAL 102161). Inset: gnathotectum and labrum + salivary stylets.

FIGURES 69–70. Heterozerconidae, Allozercon leytensis n. sp., idiosoma venter: 69, female (OSAL 053251); 70, male (UPLB MNH ACA-01335).

FIGURES 82–86. Heterozerconidae, leg I, male. 82, Afroheterozercon mahsbergi (OSAL 003042, published); 83, Maracazercon joliveti (paratype); 84, Heterozercon calakmulensis n. sp. (CNAC 012443); 85, Allozercon leytensis n. sp. (OSAL 053185); 86, Al. (Philippinozercon) makilingensis (OSAL 0053267, redrawn from Gerdeman et al. (2018)).

FIGURES 93–96. Heterozerconidae, leg II, male: 93, Maracazercon joliveti (paratype); 94, Heterozercon calakmulensis n. sp. (CNAC 012443); 95, Allozercon leytensis n. sp. (OSAL 053185); 96, Al. (Philippinozercon) makilingensis (OSAL 053267, redrawn from Gerdeman et al. (2018)).

FIGURES 48–52. Heterozerconidae, details idiosoma: 48, Allozercon leytensis n. sp., female, hypertrichy of setae in j1 position (OSAL 053251); 49, same for male (OSAL 106780); 50, Allozercon leytensis n. sp., male, anterolateral spines (OSAL 106780); 50a, detail antero-lateral spines; 51, Heterozercon ex Cuba, female, venter (OSAL 125446); 52, Narceoheterozercon sp., broken off spermatodactyl (red arrow) in female secondary genital opening / sclerotized tube (OSAL 159712).