Allozercon Vitzthum 1926

Klompen, Hans & Gerdeman, Beverly S., 2023, Genus-level revision of the Heterozerconoidea (Parasitiformes: Mesostigmata), Zootaxa 5322 (1), pp. 1-66 : 36-37

Allozercon Vitzthum 1926

Allozercon Vitzthum 1926: 104

[type species. Allozercon fecundissimus Vitzthum 1926 , by original designation].

Allozercon .— Womersley 1958: 129; Flechtmann & Johnston 1990: 147; Gerdeman & Garcia 2010: 93; Di Palma et al. 2015: 640; Gerdeman et al. 2018: 9 .

Asioheterozercon Fain 1989: 146

(type species Heterozercon audax Berlese 1910 by original designation); Evans 1992: 426 [junior synonym of Allozercon Vitzthum 1926 by Gerdeman et al. 2018: 9].

Alloheterozercon .— Gerdeman & Klompen 2003: 353 [incorrect subsequent spelling].

Diagnosis. Axial outgrowth of palp trochanter in male distinct and sclerotized, solid (9); setae hyp2 at least twice as long as setae hyp3 (22); insertion sternal setae st2 and st 3 in female and st 3 in male on isolated platelets (38, 40, 52); insertion sternal setae st 1 in male on isolated platelets (48); opisthogastral setae Jv5 inserted posterior to ventrianal fusion line (71); all marginal opisthosomal setae setiform (77, reversal); femora II setae al, pl, and av in male spines (105–107, shared with Maracazercon and Heterozercon ); genual and tibial setae pv on legs II in male spine-like (109, 110).

Remarks. A re-evaluation of the 11 characters listed by Fain (1989) for the genus Asioheterozercon , shows that two are included in the updated diagnosis of Allozercon listed above: palpal trochanter with its apico-internal angle strongly produced and bearing 2 setae (our character 9) and anal shield with five setae (71). Three of the remaining characters are variable among the S.E. Asian populations: tarsus and tibia of legs I much narrower than the other segments of that leg (81.2); anterior region of the dorsum with 20–40 long and stiff setae (29.1); antero-lateral margin of dorsal shield in male with numerous small spines (30.1). One is incorrect: palp trochanter in female bears only one seta. Seta v2 is in fact present and is inserted on the membranous axial outgrowth of the trochanter. However, it is highly reduced ( Fig. 39 ). The remaining characters are imprecise or refer to primitive character states at this taxonomic level. To further clarify the status of Allozercon a complete description is provided for one of the nine geographically separate populations for which we have specimens available. These nine populations originate in the Philippines (Bohol, Leyte, Mindoro, Samar, and Siquijor islands), Thailand (Saraburi and Bangkok), Laos, and India. The remaining taxa will be described in an upcoming revision of the genus.

Di Palma et al. (2015), in a study of the anatomy of the female genital system, found no indication of secondary genital openings (solenostomes) in females of an unidentified Allozercon species from Cebu island, Philippines. Examination of all available slide mounted Allozercon females also failed to find any indication of secondary genital openings either near the opisthogastral suckers (as in Heterozercon or Narceoheterozercon ) or posterior to coxae IV (as in Afroheterozercon ). In the absence of evidence to the contrary, we assume that Allozercon species do not have a secondary genital system in the females.

Immatures of an Allozercon species from Bangkok, Thailand were partially described in Gerdeman et al. (2018), but a complete description of Allozercon immatures is not yet available.

Allozercon Błaszak 1984 (Zerconidae) is a junior homonym of Allozercon Vitzthum 1926 ( Kemal & Koçak 2009; Koçak & Kemal 2008). The zerconid genus name was replaced by Blaszakzercon Kemal & Koçak ( Gerdeman et al. 2018) .

Figures

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.