Odontophotopsis Viereck

Pitts, James P. & Parker, Frank D., 2003, Description of the female and larval stage of Odontophotopsis succinea Viereck (Hymenoptera: Mutillidae), with new synonymy and notes, Zootaxa 137, pp. 1-10 : 3-9

Odontophotopsis Viereck

Type species. Odontophotopsis exogyrus Viereck, orig. desig.

Female. Head. As wide as thorax. Eyes slightly projecting, oval, finely but clearly faceted. Clypeus anterior edge emarginate medially, base swollen medially. Antennal scrobe lacking dorsal carina. Antennal tubercle well developed, separated by distance equal to width of single tubercle, transversely rugose. Antenna 12­segmented. Pedicel and flagellomere II subequal in length, flagellomere I slightly longer than pedicel ( Fig. 1). Mandible bidentate apically ( Fig. 2). Dorsal margin of mandible lacking prominent carina ( Fig. 2). Ventral margin of mandible emarginate on basal third with distinct basal tooth ( Fig. 2). Genal carina absent. Maxillary palpus 6­segmented, labial palpus 4­segmented. Decumbent plumose pubescence present on frons and vertex.

Mesosoma . Pyriform, slightly longer than wide, widest medially ( Fig. 4). Anterolateral margin of pronotum slightly angulate with vertical carina ( Fig. 3). Scutellar scale present with lateral carina connecting scale to propodeal spiracle tubercles ( Figs. 3, 4). Propodeum with distinct disk and declivity regions ( Fig. 3). Decumbent plumose pubescence present on metasomal dorsum. Femora of all legs rounded apically. Tibial spurs pectinate.

Metasoma. First segment subsessile with respect to second, slightly disciform posteriorly ( Fig. 5). T2 with lateral felt line. S2 flattened medially, without lateral felt line. T6 with pygidial area defined laterally by carinae. Plumose pubescence present both on surface of tergites and as dense apical fringes.

Distribution. Western North America, east to Arkansas, from B.C. Canada south into Central America (Northern Costa Rica).

Comments. The genus Odontophotopsis is in the subfamily Sphaeropthalminae (Sphaeropthalmini). Males of Odontophotopsis can be separated from other Sphaeropthalmini by the presence of large ocelli, simple spine­like sternal processes (absent in O. mamata Schuster and in some specimens of species in the O. tapajos speciesgroup), usually with weak sculpturing and the integumental surface polished, presence of incomplete parapsidal furrows (complete in O. fallax Viereck and O. pudica (Melander)) , absence of or very short felt lines on the second sternite, presence of well­developed plumose pubescence (especially on the abdomen), and presence of three or four mandibular teeth (mandibles bidentate in the O. unicornis species­group) ( Schuster 1958).

The female of Odontophotopsis can be distinguished from females of other sphaeropthalmine genera by the following combination of characters: presence of plumose pubescence, absence of dorsal carina on the antennal scrobe, antennal flagellomere I being only slightly longer than the pedicel, absence of genal carina, presence of a scutellar scale connected to a transverse carina, first metasomal segment subsessile and slightly disciform, and presence of lateral carinae defining pygidium. These characters are thought to be of generic importance and were chosen after a survey of approximately ten other undescribed probable Odontophotopsis females. Because the female of only one of 59 species has been described, it is unclear which characters are autapomorphic, if any, for the females and it is anticipated that the generic description will need to be modified as more females are described.

Several described female species currently placed in Sphaeropthalma (Photopsis) Blake but not associated with males may be Odontophotopsis species, such as S. (P.) arota (Cresson) , S. (P.) ceres (Fox) and S. (P.) zenobia (Blake) , as well as several others. However, these species do not completely match the above generic description. As such, we feel that we should attain a better understanding of the generic characters for Odontophotopsis females by studying females from definitive sex associations before placing described species into Odontophotopsis .

In the key to the mutillids of the United States ( Manley and Pitts 2002), the Odontophotopsis female will terminate at couplet 16 with a choice between Dilophotopsis Schuster and Sphaeropthalma (Photopsis) . Dilophotopsis females are much larger in size, have a transverse carina on the antennal tubercle, have a dorsal carina abruptly terminating at a distinct denticle on the basal third of the mandible ( Fig. 8), have a granulate pygidium, and exhibit differences in plumose pubescence and the shape of the first metasomal segment. Photopsis females that could be confused with Odontophotopsis , such as S. (P.) orestes (Fox) or S. (P.) marpesia (Blake) have a dorsal carina on the antennal scrobe, have a granulate or coarsely rugose pygidium, and lack a scutellar scale. This last character may not be a reliable generic character because it is known to vary within other genera, such as Dasymutilla Ashmead.

Odontophotopsis (Odontophotopsis) succinea Viereck

Odontophotopsis succinea Viereck, Proc. Acad. Nat. Sci., Phila. , 54:741­743, male, 1902. Odontophotopsis annulatus Baker, Invertebrata Pacifica , 1:94­96, male, 1905. NEW SYNON­ YMY.

Female. Head. Head brown orange, clothed with sparse erect white brachyplumose pubescence, also clothed with dense decumbent white plumose pubescence. Clypeus clothed with erect white brachyplumose pubescence. Eye width 0.44 mm, distance to occipital margin from posterior eye margin 0.26 mm. Eyes convergent ventrally. Malar space 0.7X maximum eye width. Pedicel length 0.10 mm ( Fig. 1). Flagellomere I slightly longer than pedicel ( Fig. 1). Flagellomere II slightly shorter than I, equal in length to pedicel ( Fig. 1). Antenna concolorous with head. Antennal scrobe not carinate dorsally. Front with small confluent punctures. Mandible orange, red brown distally. Dorsomedial portion of head with inconspicuous transverse tumid region just anterior to occipital carina, only visible at certain angles.

Mesosoma . Mesosoma and coxae brown orange, femora and tibiae dark brown. Mesosoma with erect orange brown brachyplumose pubescence. Metanotal area and propodeal dorsum also with decumbent orange white plumose pubescence, denser posteriorly. Propodeum with only erect white brachyplumose pubescence posteriorly. Legs with both erect white brachyplumose and decumbent white plumose pubescence. Anterolateral margins of pronotum angulate with vertical carina ( Fig. 3). Transverse sinuate carina present anterior to scutellar scale, similar in size to scale. Scutellar scale broadly bidentate. Lateral area of pronotum sparsely punctate with decumbent white plumose pubescence. Mesopleura with posterior half punctate with erect white brachyplumose pubescence; anterior half sparsely punctate with decumbent white plumose pubescence. Propodeum laterally sparsely punctate with decumbent white plumose pubescence. Mesosomal dorsum punctures similar to head, closely spaced. Punctures of vertical portion of propodeum small and sparsely spaced, distance apart at least 2X ­width of puncture. Declivity of propodeum flattened medially.

Metasoma. Brown orange. T1 with sparse long erect white brachyplumose and short plumose pubescence. T1 flattened medially with small widely spaced punctures, distance apart at least 2X width of puncture. Anterior margin of T2 with moderate punctures, distance between punctures equal to width of puncture. Surface of T2 with denser punctures, some confluent, and with erect orange brachyplumose pubescence. T2 felt line 0.36X length of T2. T2­T5 and S2­S5 with dense orange white plumose pubescence fringe that obscures following tergite, and with sparse erect orange white brachyplumose pubescence. S2 with median tumid region on anterior sixth, flattened medially. T6 finely longitudinally rugose.

Length. 5.25 mm.

Male Larva. Body. Ten pairs of spiracles, second thoracic pair minute. Spiracles small, spiracular atria unarmed, subatria elongate. Integument lacking setae, clothed densely in spinules separated by 0.5­1.0X their own length.

Head: 1. 2 X as wide as high, height measured to apex of clypeus, unpigmented except for apical half of mandible. Side of head more convex than vertex. Parietal bands elongate, faintly pigmented. Antennal orbit below middle of head capsule, located on large, circular elevated area; each with three sensilla. Head with several scattered setae. Mandible more than 2.0X as long as wide at base, without setae, terminating in four teeth in same plane, basal tooth much smaller, two preapical teeth subequal in size, smaller than apical tooth, length of second tooth from apex ~0.5X length of apical tooth ( Fig. 6). Labrum bilobed, each lobe with 14­15 sensilla, some bearing minute setae, apical median margin spinulose. Maxilla with several setae laterally, minutely spinulose mesally. Maxillary palpus much wider than long, with three apical sensilla. Galea smaller than palpus, similarly formed, each with two sensilla. Labium broad, with a few small apical setae. Labial palpus much broader than long, with 4 sensilla. Spinneret a transverse slit, widened medially.

Length. 4­6 mm.

Type Material Examined. Odontophotopsis succinea , Holotype male, CA, La Jolla, Aug., Cockerell, ANSP. Odontophotopsis annulata , Holotype male, CA, Claremont, CUIC.

Material Examined. USA: CA: Davis, 1 female, 3 males X. 1964, rearing no.3102, F.D. Parker ( BBSL, JPPC); Monterey Co., Big Sur, 1 male, 7.VII. 1938, M. Cazier (UMC); San Diego Co.: Jacumba, 1 male, 20.VII. 1949 ( UMSP), D.J. and J.N. Kissell; Live Oak Springs, 1 male, 11.VII.1923 ( UMSP); Mission Dam, 3 males, 21.VI ( UMSP); Pine Valley, F.W. Kelsey: 1 male, 25.Vl­ 4.VII.1927, (UMC); 1 male, 18.VII.1927, 1 male, 20.VII.1927, 1 male, 19.VIII.1927, 1 male, 11.IX.1927, 1 male, 21.IX.1927, 1 male, 26.IX.1927, 1 male, 28.VIII.1927, ( UMSP); 1 male, 19.VIII.1927, (UMC); San Diego, 5 males, C.E. Ricksecker ( NMNH, UMSP); Vallecitos, 1 male, 27.IX. 1936 ( UMSP); Santa Cruz Co.: Santa Rosa Mts., 1 male, 15.VI.1946, D.J. and J.N. Kissell (UMC).

Host. Three males and one female reared from Oxybelus uniglumis (L.).

Discussion. The male holotypes of O. annulata Baker and O. succinea Viereck were studied and found to be conspecific. Both are characterized by deeply excised mandibles that are dilated beyond the excision, infuscated flagellomeres, posteromedian margins of clypeus produced into a weak transverse ridge, a nitid pygidium that is not defined laterally by carinae, weakly infuscated tarsi, and a marginal cell length along the costa that is equal to the length of the pterostigma. The genitalia of both types were studied and found to be identical ( Figs. 9, 10 ). The holotype of O. annulata has a weak tubercle a short distance from each mesosternal process. These tubercles were found to be present in a few of the specimens studied, but absent in most. No other differences could be found between specimens with tubercles versus those without tubercles.

There is some variation in the male O. succinea specimens that were studied. Length ranged from 7 to 11 mm. The infuscated coloration of the flagellum, legs and tarsi varies in intensity from very dark to almost absent. The infuscated coloration, however, is dark in both of the holotypes.

Several problems were found in Schuster (1958) in relation to O. succinea . Firstly, Schuster placed O. succinea in the melicausa species­group and keyed it out there, but he also keyed this species out as O. annulata in the O. parva species­group. Schuster stated that the species O. annulata (now O. succinea ) and O. viereckii Baker appear to be close to or identical with O. cookii Baker ( Schuster 1958) and that “all three forms perhaps should be treated as members of the [ melicausa species­group]." After studying the holotype of O. cookii (CUCI: Claremont, California), it was found that this is not the case. Odontophotopsis cookii clearly belongs in the O. parva species­group. It differs markedly from the other two species by having the sculpture of the pygidium granulate and having only a slight excision, but not a distinct basal tooth, on the ventral margin of the mandible, as opposed to O. succinea ( Fig. 7).

Secondly, after studying the holotype of O. viereckii (CUCI: Ormsby Co., Nevada), it was found that it does belong in the O. melicausa species­group, but was left out of Schuster’s key. It will key to O. succinea . Odontophotopsis viereckii has the legs completely honey­colored. In O. succinea , at least the distal portions of the femora and tibiae are infuscated, but ranges from almost completely stramineous to completely black. The genitalia differ from O. succinea by the cuspis being slightly longer and spatulate apically. Also, the length of the aedeagus of O. viereckii is much more than 2X its basal height (as opposed to Figs. 9, 10 ).

We were able to base our larval description on an exuvium of a larva. The resolution obtained by clearing the exuvium was comparable to that of a freshly prepared larva, except that we were unable to study the natural shape of the larva or the form of the tenth abdominal segment.

The description of the larva of O. succinea generally agrees with the description of the Mutillidae larval stage as given by Evans (1987). The head capsule and integument of O. succinea is very similar to Sphaeropthalma pensylvanica (Lep.) . It differs from S. pensylvanica , however, in having spinules more densely clothing the body and in having a larger first mandibular tooth that is approximately equal to 2X length of second tooth (for S. pensylvanica , the first mandibular tooth is length is <1.5X length of second tooth).

Figures

FIGURES 9 ­ 10. Odontophotopsis succinea male: 9, genitalia with aedeagus removed, internal view; 10, aedeagus; scale = 0.3 mm (same for Figs. 9 ­ 10).