Polysphincta Gravenhorst, 1829

Khalaim, Andrey I., Ruíz-Cancino, Enrique & Coronado-Blanco, Juana María, 2024, Darwin wasps of the subfamily Pimplinae (Hymenoptera: Ichneumonidae) of Mexico: Polysphincta genus-group, Zootaxa 5458 (2), pp. 151-196 : 173-174

Genus Polysphincta Gravenhorst, 1829

Polysphincta Gravenhorst 1829: 112 . Type species: Polysphincta tuberosa Gravenhorst, 1829 , by subsequent designation ( Westwood 1840: 59).

References. Cresson 1870: 149 [3 species (2 described as new) in America north of Mexico; key]. Cushman 1920: 21 [subgenus of Polysphincta s.l.; review of 7 species (1 described as new) from North America; key]. Townes & Townes 1960: 245 [description; review of 5 specis (1 described as new) from Nearctic region; key]. Townes & Townes 1966: 18 [catalogue; 1 species in Neotropical region; 1 species in Mexico]. Townes 1969: 106 [diagnosis]. Carlson 1979: 337 [catalogue; 5 species in North America]. Gauld 1991: 308 [description; review of 6 species from Costa Rica (all described as new); key]. Gauld et al. 1998: 41 [7 species (1 described as new) in Costa Rica; key]. Gauld et al. 2002: 43 [2 species in El Salvador (including 1 unidentified species); key]. Ruíz-Cancino et al. 2002: 645 [checklist; 3 species in Mexico]. Kloss et al. 2016a [host, biology; Brazil]. Kloss et al. 2016b [host, biology; Brazil]. Higa & Penteado-Dias 2020: 382–383 [2 new species from Brazil; key]. Eberhard 2021 [ Costa Rica; biology]. Pádua et al. 2021 [7 new species from South America; key].

Polysphincta is a predominantly Holarctic and Neotropical genus with about 30 species. Five species occur in Nearctic region (one of them also occurs in Palaearctic region), seven in Central America and about 11 species in South America. Seven species are recorded here from Mexico, including two new species. All Mexican species possess a distinct epomia ( Figs 42 , 44 , 48 ).

Species of Polysphincta are koinobiont ectoparasitoids of adult spiders, mainly the family Araneidae . The larva of the parasitoid induces the host spider to spin a modified “cocoon web” ( Eberhard 2010, 2019, 2021).

Polysphincta thoracica (Cresson) is known to us only from its brief original description ( Cresson 1874), therefore this species is not included to the key.

Key to species of Polysphincta occurring in Mexico

1. Mesoscutum orange with anterolateral sides broadly white ( Fig. 44 ). Propodeum black ( Fig. 44 ). First sternite in profile without projection ventrally. Ovipositor shorter than hind tibia ( Fig. 43 )................................................ 2

– Mesoscutum either entirely orange or orange with black markings. Propodeum black or orange. First sternite in profile sometimes with distinct projection ventrally. Ovipositor at least as long as hind tibia................................ 3

2. Submetapleural carina complete ( Fig. 44 ). Legs white with black markings ( Fig. 57 ). Metasomal tergites black ( Fig. 43 )..................................................................................... 2. P. gutfreundi Gauld

– Submetapleural carina absent. Legs white with a few orange and brownish markings. Metasomal tergites dark reddish brown, tergites 2–5 with black bands posteriorly.................................................... 7. P. xena sp. nov.

3. Mesoscutum with median blackish mark ( Fig. 49 ), upper posterior corner of mesopleuron black ( Fig. 48 ). Legs without distinct black marks, all femora orange-brown ( Figs 46, 47 ). [Pronotum with a distinct mediodorsal forward-projecting tubercle. Nervellus in hind wing with distinct angulation ( Fig. 48 ). First sternite without protuberance ventrally, at most with a slight swelling ( Fig. 48 ).].................................................................. 3. P. koebelei Howard

– Mesoscutum and mesopleuron entirely orange-brown ( Figs 42 , 52 ). Legs usually whitish, sometimes with conspicuous black or brown markings.................................................................................... 3

3. Pronotum with a strong mediodorsal shelf-like projection ( Fig. 42 , arrow). First tergite robust ( Fig. 42 ), 1.2–1.3× as long as posteriorly broad. First sternite in profile without distinct projection ventrally, at most with a slight swelling. Hind wing with distal abscissa of CU vestigial but its position discernible by an angulation of nervellus. [Legs whitish without black markings. Ovipositor 1.3–1.4× as long as hind tibia.]................................................. 1. P. albipes Cresson

– Pronotum without a mediodorsal shelf-like projection ( Fig. 52 ). First tergite slender, 1.6–2.0× as long as posteriorly broad. First sternite in profile with a distinct projection ventrally ( Fig. 52 , arrow). Hind wing with distal abscissa of CU absent and nervellus not angled ( Fig. 55 )................................................................................... 4

4. Hind leg with apices of tibia and all tarsomeres black ( Fig. 53 ). Ovipositor 1.2–1.4× as long as hind tibia ( Fig. 50 )............................................................................................. 4. P. purcelli Gauld

– Hind leg without black markings, at most extreme apices of tibia and tarsomeres brownish. Ovipositor 0.9–1.0× as long as hind tibia................................................................................ 5. P. sirena sp. nov.

Figures

FIGURES 40–42. Polysphincta albipes, ♀ (Tamaulipas): 40—habitus, lateral; 41—head, front; 42—mesosoma and base of metasoma, lateral.

FIGURES 43–45. Polysphincta gutfreundi, ♀ (Chiapas): 43—habitus, lateral; 44—mesosoma and base of metasoma, lateral; 45—apex of metasoma with ovipositor, lateral.

FIGURES 46–49. Polysphincta koebelei, ♀ (46, Tlaxcala) and ♂ (47–49, Tamaulipas): 46, 47—habitus, lateral; 48—mesosoma and base of metasoma, lateral; 49—anterior part of mesosoma, dorsal.

FIGURES 57–61. Polysphincta albipes var., ♀ (Michoacán): 57—habitus, lateral; 58—head, front; 59—mesosoma and base of metasoma, lateral; 60—propodeum, dorso-lateral; 61—apex of hind tarsus, lateral.

FIGURES 50–54. Polysphincta purceli, ♀ (50–53) and ♂ (54) (Tamaulipas): 50, 54—habitus, lateral; 51—head, front; 52— mesosoma and base of metasoma, lateral; 53—hind leg, lateral.

FIGURES 55–56. Polysphincta purceli, ♀ (Tamaulipas): 55—wings; 56—apex of metasoma with ovipositor, lateral.