Photomorphus (Photomorphina) subtenuis (Viereck)

Brabant, Craig M., Williams, Kevin A. & Pitts, James P., 2010, True females of the subgenus Photomorphina Schuster (Hymenoptera: Mutillidae), Zootaxa 2559, pp. 58-68 : 64-65

Photomorphus (Photomorphina) subtenuis (Viereck) , REVISED STATUS

( Fig. 4 )

Odontophotopsis subtenuis Viereck, 1904 . Amer. Ent. Soc., Trans. 30: 85. Holotype male: Texas [ANSP]. Photomorphus (Photomorphina) myrmicoides Mickel, 1965 . Proc. Ent. Soc. Wash. 67: 3. Misidentification, based on sex association with misidentified female.

Diagnosis of female: Females of Photomorphus subtenuis can be separated from other females in the subgenus from the eastern USA by the following characters: mandible with obscure ventral tooth basally; pygidium with longitudinal striae; and mesosomal dorsum and T2 with scattered pale brown setae ( Fig. 4 ).

Description of female: Length. ~ 3.5–4.5 mm. Coloration and Setal Pattern. Integument of body light ferruginous. Legs concolorous with mesosoma. Antennal flagellum concolorous with head. Dorsum of head, mesosoma, and metasoma clothed with short reddish-brown to golden-reddish simple and brachyplumose setae dorsally; longer, distinctly brachyplumose, whitish setae present on propodeum and T1; setae of head often white or lighter in color than those of mesosoma and T2. T2–5 with sparse fringe of pale plumose setae. Disk of T2 with appressed and erect ferruginous setae.

Head. Head rounded posteriorly, subequal in width to the mesosoma at its widest point, moderately punctate. Head evenly rounded in lateral view; occipital region straight and gena evenly rounded. Eye ovate. Clypeus protruding anteriorly, posteromedially produced into low triangular tubercle with fringe of plumose setae projecting ventrally. Malar space parallel in frontal view. Antennal scrobe without dorsal carina. Antennal tubercle subglabrous, impunctate. Flagellomere 1 ~1.2X length of pedicel. Flagellomere 2 ~1.2X length of pedicel. Flagellomeres 2–10 slightly produced apically on ventral side; surface densely, finely punctate, appearing dull. Mandible bidentate apically, attenuated towards apex. Ventral mandibular margin with small, sharp (angulate rather than rounded) basal tooth. Genal carina absent. Hypostomal carinae lamellate medially.

Mesosoma. Mesosoma widest in mesonotal region, longer than broad. Mesosoma coarsely punctate dorsally. Propleuron anterodorsally and mesopleuron medially running vertically punctate. Epaulet not prominent. Scutellar scale broad, but not obviously distinct from surrounding sculpture. Distinct transverse carina present on mesonotum anterior to scutellar scale. Mesosternum with low transverse tubercle present medially just anterior to mesocoxa. Metasternum with medial projection, extending dorsoventrally between hind coxae. Propodeum rounded, without distinct dorsal and vertical faces.

Metasoma. Segment 1 broadly sessile with segment 2. T1 with small sparse punctures. T2 with evenly distributed, moderate punctures. T2 with felt line; length 0.5X length of tergite. T3–5 shagreened. T6 with distinct pygidial area defined laterally by carinae; surface obviously striate, striae vary from being present only on basal half of pygidium to continuous throughout length of pygidium. S2–5 with punctation similar to tergites.

Distribution. Widespread in the Great Plains, from Texas to Iowa.

Material examined: USA, Iowa, Plymouth Co.: Sioux City: 12.Jul.1924, C.N. Ainslie (1 Ψ, UMSP); 8.Aug.1928, C.N. Ainslie (3 Ψ, UMSP); 11.Aug.1928, C.N. Ainslie (1 Ψ, UMSP); 20.Jul.1933, C.N. Ainslie (1 Ψ, UMSP); 11.Aug.1933, C.N. Ainslie (1 Ψ, UMSP); Kansas, Riley Co.: 13.Apr, J.B. Norton (1 Ψ, UMSP); Missouri, Jefferson Co.: Maxville, 1.Aug.1938 (1 Ψ, UAIC); Nebraska, Morrill Co.: Chimney Rock National Historic Site, 5.Aug.2006, K.A. Williams (1 Ψ, EMUS).

Remarks. Based on a series of seven females and ten males from Iowa, Mickel (1934) associated females that he identified as P. m y r m i c o i d e s with these males, which he failed to recognize as the already named P. subtenuis . These females, however, are not conspecific with the holotype of P. myrmicoides . Only after Schuster (1958) included P. s u b t e n u i s in his key to the nocturnal mutillids of North America did Mickel associate the name P. subtenuis with the females he had called P. myrmicoides . Mickel (1965) realized his oversight and placed P. subtenuis as a junior synonym of P. myrmicoides . Because of his initial misidentification of the female, Mickel’s (1965) synonymy of P. s u b t e n u i s with P. myrmicoides is incorrect. Photomorphus subtenuis is reinstated here and the true females of this species are described for the first time. See Fig. 7 for a summary of these taxonomic changes.

The females of P. subtenuis can be immediately separated from P. m y r m i c o i d e s by setal pattern and sculpturing: the lateral face of the propodeum is glabrous, the propodeum has erect brachyplumose setae, T1 has erect brachyplumose setae, and there are distinct plumose bands on T2–4.

This is one of the most widespread Photomorphina species; in its southern and western ranges (Texas, western Plains States) it shares overlapping distribution with other Photomorphina species [e.g., P. j a s o n (Fox)] that are currently known only from males. In these regions, the female diagnostic characters are probably too general for explicit identification, until more females are associated.

Figures

FIGURE 7. Chronology of taxonomic changes discussed herein.

FIGURES 1 − 6. Habitus, female. 1, Photomorphus archboldi (Florida); 2, P. auriventris (Wisconsin); 3, P. s p i n c i (South Carolina); 4, P. subtenuis (Nebraska); 5, P. impar (South Carolina); 6, P. myrmicoides (Missouri).