Parkerodynerus erythrogaster (Bohart, 1939) Fateryga, 2021

Fateryga, A. V., 2021, Two new Nearctic genera in the tribe Odynerini s. str. revealed on the bionomics and morphology, with a comment on the cocoons of the eumenine wasps (Hymenoptera: Vespidae: Eumeninae), Far Eastern Entomologist 427, pp. 1-19 : 11-16

Parkerodynerus erythrogaster (Bohart, 1939) , comb. n.

Figs 12 , 23–31

Monobia bicolor Provancher, 1888: 420–421 , ♀ (type locality: “ Anaheim ” [ USA: California]), holotype, ♀, in the collection of the Smithsonian National Museum of Natural

History, Washington, D.C., USA. Junior secondary homonym in the genus Odynerus

Latreille, 1802, nec de Saussure, 1855.

Odynerus erythrogaster Bohart, 1939: 81–82 , replacement name for Odynerus bicolor (Provancher, 1888) .

MATERIAL EXAMINED. USA: California: San Bernardino County, Redlands , 1 ♂ ,

leg. F. R. Cole, ex coll. K.W. Cooper [ FSCV]; San Diego County, Borrego Valley, Palm

Canyon, 1 ♀ (boring no. 2574B), 1 ♂ (boring no. 2565A), leg. F.D. Parker [ FSCV]; Inyo

County , Big Pine Creek, 7500′, 20.VI 1942, 1 ♂, leg. R. M. Bohart [ CDFA]; Napa County ,

Samuel Spring, 13.V 1954, 1 ♀, leg. R. M. Bohart [ CDFA]; Los Angeles County, Tanbark

Flat, 25.VI 1958, 1 ♀, leg. R. M. Bohart [ CDFA]; Santa Barbara County, Sunset Valley ,

16. VI 1982 , 2 ♀, leg. A.J. Gilbert [ CDFA].

DISTRIBUTION. USA (Arizona, California), Mexico (Baja California) .

REMARKS. The name Monobia bicolor being junior secondary homonym replaced before 1961 is permanently invalid (Art. 59.3 of ICZN, 1999).

BIONOMICS. Bohart (1951) was first who reported the nesting of this species in elderberry twigs ( Sambucus spp. ) while Parker & Bohart (1968) reported it utilizing pre-existing cavities of trap nests, but only Parker (1984) described the nests in detail. He studied a total of 207 nests; all of them were constructed in artificial borings in elderberry and raspberry

( Rubus spp. ) canes inserted vertically into the ground. The borings were of different diameters:

3 mm, 6 mm, and 9 mm; the narrow borings were widened and often lengthened by the female wasps, the medium borings were only lengthened but not widened, and the broad ones were not modified. The nests contained from 1 to 11 cells (mean values in different boring diameters were from 2.9 to 3.6) provisioned with gelechiid caterpillars. The partitions between the cells were made of packed sand while the closing plug was made of packed sand too but in some nests it contained also bits of debris. Apparently, the wasps did not use any liquid while constructed both the cell partitions and the closing plug.

1939), a whole cocoon with the opening made by the emerged wasp; 33 – Paravespa rex

(von Schulthess, 1924), a dissected cocoon with some clayish substrate remaining laterally and at the bottom of the cell, arrow indicates the free part having a sandwich-like structure.

Parker (1984) described the cocoon of P. erythrogaster, which I also had an opportunity to study ( Fig. 32 ). He paid an attention to the fact that this cocoon differed principally from the cocoons of most other representatives of the eumenine wasps, which constructed cocoons merely by lining the cell walls with silk. In the case of P. erythrogaster, the larva started cocooning with making a bag-like case of silk that was not firmly attached to the cell walls.

Then, it removed pieces of sand from the partition above the cell and used them to line the inside of the case. After that, the larva finished the inside of the cocoon by depositing the inner layer of silk over the sand particles. Dissection of a complete cocoon of P. erythrogaster confirmed its sandwich-like structure ( Fig. 34 ) described by Parker (1984). The outer layer,

looked from the outside like a whitish cobweb ( Fig. 32 ), consisted of a chaotic interweaving of silk strands ( Fig. 35 ). The thickest middle layer was represented by sand particles ( Fig.

34). The thinnest inner layer consisted of mostly broad strands and presumably airtight films of silk, with an inclusion of some sand microparticles, apparently penetrating there from the middle layer ( Fig. 36 ).

Parker (1984) also reported that the species was univoltine and hybernating at the prepupal stage; the sex ratio was female-biased (1.2: 1). He also provided data on the nest associates:

predators and brood parasites. An unusual feature was a low immature mortality: about 22%

(14.8% due to the nest associates and 7.1% due to unknown reasons).

(Bohart, 1939) (34 – dissection of a lateral part; 35 – detached outer layer from the inside; 36

– inner layer from the inside); 37–39 – Odynerus (Odynerus) spinipes (Linnaeus, 1758) (37 –

dissection of a free part; 38 – dissection of a lateral part with some clayish substrate forming the middle layer; 39 – inner layer from the inside). Arrows indicate the inner layer; figure parentheses indicate the outer layer.

There are no doubts that either Bohartodynerus or Parkerodynerus cannot be merged into the genus Odynerus . They are even more different from Odynerus than some Palaearctic genera

(first of all, Gymnomerus ) which have been already separated from it by Blüthgen (1938a,

1938b, 1939, 1941). Another question can be arisen: why Bohartodynerus and Parkerodynerus were described above as two genera instead of a single genus for all the members of the “red”

complex? The answer is that there are no strong evidences of their sister phylogenetic rela-

tionships. As was stated above, Bohartodynerus and Parkerodynerus share the following characters which distinguish both genera from Odynerus : a narrow apical margin of the clypeus, the absence of distinct pronotal foveae, sharply impressed notauli and distinct parapsidal lines, the tegula with a small but evident inner posterior angle where it adjoins the scutum, a dense short pilosity of the posterior sterna in the male, and a reddish pattern. Most of these characters are of plesiomorhic state (such as sharply impressed notauli or the tegula shape, Carpenter & Cumming, 1985) or cannot be considered as apomorphic without doubts

(such as clypeal shape or body coloration). The only possible clear synapomorphy is a dense short pilosity of the posterior sterna in the male but it is also arizen independently in

Paragymnomerus and Tropidodynerus , as well as several representatives of the Pterocheilus group. As for the similar color pattern of the two newly described genera, it is not surprising since it can be merely a case of the Müllerian mimicry that is rather common in the eumenine wasps (Garcete-Barrett, 2014; Selis, 2020).

Therefore, I prefer to recognize Bohartodynerus and Parkerodynerus as two separate genera until they are studied phylogenetically (preferably involving molecular data) despite the opinion that the “proliferation of genera is merely the sort of extreme splitting” (Carpenter

& Garcete-Barrett, 2002: 52). If further studies will show their sister position, they can be treated as subgenera of a single genus. The differences between Bohartodynerus and Parkerodynerus are, however, at least not less than those between Odynerus and Gymnomerus . In both pairs of these genera there are differences in the female clypeus and cephalic foveae, as well as the male legs and genitalia (they are, however, quite similar in Odynerus and Gymnomerus , while very different in Bohartodynerus and Parkerodynerus ). Unfortunately I did not have a chance to examine the genitalia of Bohartodynerus but the drawing in Bohart (1939:

79, fig. 3) allows to consider them different enough from those of both Odynerus and Parkerodynerus .

Different kinds of cephalic foveae and distinct notauli are also present in the genus Symmorphus Wesmael, 1836 (Cumming, 1989) but it is hardly possible that the latter one is closely related to Bohartodynerus and Parkerodynerus . It rather means that both groups

( Symmorphus and the “red” complex of two newly described genera) are generalized (posses a significant number of plesiomorhic characters) that is confirmed by the basal phylogenetic position of Symmorphus within its clade on the “molecular” cladograms (Bank et al., 2017;

Piekarski et al., 2018).

It is worthy to mention, that each genus in the Odynerus group of the tribe Odynerini

s. str. has their peculiar nesting bionomics and there are no genera sharing all the main behavioral characters of the females ( Table 1). At the same time, species within each genus have very similar bionomics; they differ mainly in the ecological preferences of a certain type of landscape or a certain species of prey within the given prey group, as well as in the minor details of the nest parameters. This is true for several species of Odynerus , which were studied bionomically (e. g., Miotk, 1979; Bohart et al., 1982; Schaber, 1985; Haeseler, 1997;

Fateryga, 2013 ), two studied species of Paragymnomerus (Móczár, 1939; Fateryga, 2018 ),

four studied species of Paravespa (Blüthgen, 1957; Gess & Gess, 1988; Fateryga & Ivanov,

2013), and two studied species of Tropidodynerus (Ferton, 1895; Arens, 1999; Fateryga,

2009). The genus Gymnomerus is monotypic and has very specific, unique nesting habits

(e. g., Fateryga, 2012 ), that is true for the genus Parkerodynerus as well. Neither Bohartodynerus nor Parkerodynerus can be treated as members of the genus Odynerus according to their ethology, and the differences between these two newly described taxa are also enough to recognize them as separate genera ( Table 1).

s. str.

* – can be often modified (enlarged) by the female wasp. The data on most of the genera

(except first two) are from my previous papers ( Fateryga, 2009 , 2012, 2013, 2018; Fateryga

& Ivanov, 2013) and references therein.

In my previous papers, I described cocoons of Tropidodynerus and Gymnomerus as consisting of a single thick layer ( Fateryga, 2009 , 2012). Then, I described cocoons of

Odynerus , Paravespa , and Paragymnomerus ( Fateryga, 2013 , 2018; Fateryga & Ivanov,

2013) as consisting of an outer silk layer at its free part and an inner thick layer “made with the help of fluid secretion penetrating into the cell walls and making them durable and water-

proof” (e. g., Fateryga & Ivanov, 2013: 595; Fateryga, 2018: 437 ). That was not true.

Detailed re-examination of the cocoons of Paravespa ( Fig. 33 ) and Odynerus ( Figs 37–39 )

revealed that they actually had a sandwich-like structure ( Fig. 37 ), similar to that in the cocoon of Parkerodynerus , but present only at the free part (= proximal end) of the cocoon instead over its whole surface (cf. Fig. 40 with Fig. 41 ). Therefore, cocoons of Paravespa and

Odynerus cannot be easily detached from the substrate ( Fig. 33 ). Their outer layer is made of a loose chaotic interweaving of silk strands and films ( Fig. 37 ) in the form of a convex meniscus at a distance from the inner surface of the outer cell partition. Thus, the outer layer is present only at the proximal end of the cocoon while the middle layer (consisting of soil,

Figs 37, 38 ) and the inner one (consisting of mostly broad silk strands, Fig. 39 ) are present over the whole cocoon surface ( Fig. 41 ). Such cocoon structure is apparently peculiar also to

Gymnomerus , Paragymnomerus , and Tropidodynerus .

whole cocoon have a sandwich-like structure, its outer layer is loose, prey feces are supposed to be above the cocoon, the inner surface of the cell plug is not covered with silk); 41 – Odynerus ,

Paravespa , and probably most other Odynerini s. str. (only the free part have a sandwich-like structure, its outer layer is loose, prey feces are above the cocoon, the inner surface of the cell plug is not covered with silk); 42–44 – most other Eumeninae s. str. (42 – one layer, prey feces are below the cocoon; 43 – two layers, prey feces are below the cocoon; 44 – two layers, prey feces are between them).

One more common trait of the cocoons of Parkerodynerus and other members of the

Odynerus group is that the inner surface of the outer cell partition is not covered with silk

( Figs 40, 41 ). Cocoons of most other wasps in the subfamily Eumeninae s. str. completely cover the inner surface of the cell including the outer partition (Figs 42–44). They can be also consisted of several layers (Figs 43, 44) but these layers are made of silk only; none of such cocoons have a sandwich-like structure involving sand or soil (Figs 43, 44). Therefore,

cocoons of Parkerodynerus are outstanding among other Odynerini s. str. but the whole group of Odynerini s. str. , in its turn, differs enough from the remaining eumenine wasps in its habits, particularly the cocooning behavior.

Figures

Figs 7–12. Aedeagus, dorsal view: 7 – Paravespa (Paravespa) quadricolor (Morawitz,

Figs 23–31. Parkerodynerus erythrogaster (Bohart, 1939): 23–27 – female (23 – habitus,

Figs 32–33. Cocoons of Odynerini s. str.: 32 – Parkerodynerus erythrogaster (Bohart,

Figs 34–39. Cocoons of Odynerini s. str.: 34–36 – Parkerodynerus erythrogaster

Figs 40–41. Schematic plans of the eumenine wasp cocoons: 40 – Parkerodynerus (the