Palmodes Kohl, 1890

Danilov, Yuriy N. & Byvaltsev, Alexander M., 2020, The digger wasps of the genus Palmodes Kohl, 1890 in Central Asia (Hymenoptera Sphecidae: Prionychini), Zootaxa 4803 (3), pp. 401-434 : 405

Genus Palmodes Kohl, 1890

Palmodes Kohl, 1890:112 . Type species: Chlorion occitanicum ( Lepeletier de Saint Fargeau et Audinet-Serville, 1828) [= Sphex occitanicus Lepeletier de Saint Fargeau et Audinet-Serville, 1828 ], designated by Fernald 1906:318.

Diagnosis. Morphologically, the genus differs well from the related genera Prionyx and Chilosphex . Palmodes closely resembles Chilosphex by the shape of the clypeus, the claws with two ventral teeth and by lacking the placoids on the male antennae, but differs in having a distinctly defined tarsal rake of the female foreleg and by the rectangular male S8 with the apical margin slightly emarginate or triangular ( Chilosphex has no defined tarsal rake on the female foreleg and male S8 is rectangular with lateral teeth). Palmodes is similar to the subgenus Calosphex (= niveatus species group) of Prionyx in having the claws with two ventral teeth and by the absence of placoids on the male antennae, but differs in lacking pale fasciae on the metasoma, and by the shape of clypeus (the clypeus of Calosphex has no distinct emargination and the metasoma has pale fasciae). Palmodes also resembles the subgenus Harpactopus (= crudelis species group) of Prionyx in having the claws with two teeth on ventral margin, but differs in lacking placoids on the male antennae and by the female clypeus which has the lateral emargination, and is divided into three lobes ( Harpactopus has the male antennae with placoids and the female clypeus without the lateral emargination, not divided into three lobes).

Description. The following are the main recognition features of Palmodes : clypeus broad, flattened, its free margin in female emarginate and divided into three lobes; male antennae without placoids; second submarginal cell of forewing higher than broad; claws with two ventral teeth; female foreleg with well-defined tarsal rake; male S4–S5 pruinose; male S8 triangular or rectangular with slightly emarginate apical margin; male volsella spatulate apically.

Species diagnostic features. The following main features are used in species determination (in both sexes): shape of the clypeus (elongation and width of medial lobe, development of lateral lobe and lateral emargination; presence and features of appressed silvery setae (goldish or brownish in some species) of clypeus, pronotum, scutum and mesopleuron; sculpture of scutum and mesopleuron. The male genitalia are uniform in Palmodes .

Coloration. The color is variable in Palmodes . The females of P. minor and P. strigulosus have partly red legs. The metasoma is reddish basally in the females of P. melanarius , P. hissaricus , P. mandarinius , P. minor , P. occitanicus , and P. strigulosus and in the males of P. hissaricus , P. mandarinius , P. occitanicus , and P. strigulosus . Most species of the genus have melanistic specimens; such specimens occur in P. melanarius (in female), P. hissaricus (in both sexes), P. mandarinius (in both sexes), P. minor (in female), P. occitanicus (in both sexes), and P. strigulosus (in male). P. orientalis shows no variability in the coloration.

Earlier classifications. The name Palmodes has been proposed for a group of species in the genus Sphex by Kohl (1890). Fernald (1906) placed Palmodes in the genus Chlorion Latreille as a subgenus and designated Chlorion occitanicum Lepeletier et Serville as the type species. Bohart and Menke 1961 treated Palmodes as a separate genus and gave a detailed generic characteristics, and continued to use this status ( Bohart & Menke 1963; 1976). In a revision of Palearctic Palmodes Roth (1963) treated the taxon as a subgenus of Sphex . In the following years Palmodes was regarded either as a distinct genus or as a subgenus of Sphex . In recent decades, it has become customary to treat it as a full genus.

Life history. The female digs a single-cell nest in different types of soil, which she provisions with Tettigoniidae ( Orthoptera : Ensifera ) from the following genera: Anabrus Haldeman , Atlanticus Scudder , Capnobotes Scud- der, Ephippiger Berthold , Montana Zeuner, Neduba Walker , Pediodectes Rehn et Hebard , Platylyra Scudder , and Tettigonia Linnaeus. The females drags the prey while walking on the ground. One nest is provisioned with one to four prey specimens. ( Bohart & Menke 1961, 1963; Kazenas 2001).