Aulacophilinus Lomholdt, 1980

Pulawski, Wojciech J., 2017, A Revision of the Wasp Genus Aulacophilinus Lomholdt, 1980 with Descriptions of Three New Species (Hymenoptera: Crabronidae), Proceedings of the California Academy of Sciences 64 (1), pp. 1-29 : 2-6

Genus Aulacophilinus Lomholdt

Aulacophilinus Lomholdt, 1980:27 .

Type species: Aulacophilinus rennellensis , by original designation and monotypy.

Synonymized with Pison by Antropov, 1999:564, resurrected by Menke, 2016.

TAXONOMIC HISTORY.— Lomholdt (1980) established the genus Aulacophilinus , a member of Trypoxylini, for his new species A. rennellensis from the Solomon Islands. He pointed out that the new genus has gastral segment I as long as in the Neotropical genus Aulacophilus and shares with it the presence of only two submarginal cells and the absence of a carina at the top of the propodeal side, but differs from it by the flagellum filiform (rather than claviform), the occipital carina continuous (rather than interrupted ventrally), and the mesopleuron non-ridged (rather than horizontally ridged). There are also three additional differences between these genera: in Aulacophilus the mandible is acuminate apically (truncate in Aulacophilinus , see below for details), the metapleuron is parallel-sided for most of its length (in Aulacophilinus the metapleuron is markedly wider above the upper metapleural pit than below it), and tergum I has a pair of longitudinal, admedian carinae (no such carinae are present in Aulacophilinus ). Antropov (1999) questioned the close relationships of these two genera, claimed that Aulacophilinus has not a single autapomorphy within Trypoxylini and that its gaster is just an extreme case of the situation in Pison , in which several species have the gaster elongate to a various degree, with the length exceeding the maximum width ( P. difficile Turner , P. icarioides Turner , P. obliteratum F. Smith , P. pistillum Menke , and P. woji Menke ; in P. icarioides segment I is bulging apically, in P. woji the basal portion is approaching the condition of Aulacophilus ). He concluded that Aulacophilinus should be treated as a specialized member of Pison and as its junior synonym. Neither Lomholdt nor Antropov, however, paid attention to the specialized, unique mandible and the specialized clypeus of Aulacophilinus . Naumann (1990b), on the other hand, recognized the importance of the broadly truncate mandible and revised the four Australian species with this character, calling them the caliginosum group of Pison . He did not recognize the close relationship of the group to Aulacophilinus rennellensis . Menke (2016), however, demonstrated that the caliginosum species group should be included into Aulacophilinus , resurrected Aulacophilinus from synonymy, provided its definition, described one new species ( A. amblygnathus ), provided a key to determination of the species known to him, and commented on the types of A. rennellensis and A. mandibulatus .

DEFINITION OF GENUS.— Aulacophilinus is characterized by a mandible that is unique within Trypoxylini: both the outer and inner surfaces are punctate and setose throughout (except narrowly impunctate and asetose adjacent to the apical margin), the acetabular and condylar grooves are absent, and the inner portion is broadly expanded preapically, thus forming an apical truncation (the apical margin of the truncation being slightly concave, e.g., Fig. 2 ). Unlike Pison , the clypeus is punctate throughout, without a shiny, medioventral lamella (see below for exception). I agree with Menke (2016) that these striking features justify recognition of Aulacophilinus as an independent genus. An undescribed Pison from Australia, however, is somewhat intermediate between Aulacophilinus and Pison : the clypeus without a lamella and the broadened preapically inner mandibular portion are as in Aulacophilinus . Unlike Aulacophilinus , however, the inner mandibular surface is impunctate and glabrous (as in Pison ), and the following are unique: two large, preapical teeth on the inner mandibular margin, a broad, shallow condylar groove, and a sharp conspicuous acetabular carina. Also, the setae of tergum I are erect (appressed in Aulacophilinus ).

The unique mandible of Aulacophilinus , clearly an outstanding autapomorphy, may be related to a particular way of nest building. Unfortunately, nothing is known about the nesting habits of the included species.

DESCRIPTION.— In addition to the specialized clypeus and mandible, the species share the following characters: eye asetose, ommatidia about equal in size; inner eye margin convergent above; frons without middle supraantennal carina except carina present in large females of A. caliginosus ; distance between antennal socket and orbit larger than socket diameter (about equal to socket diameter in female of A. rennellensis ); clypeus transverse; flagellum cylindrical, not thickened toward apex; mandibular posterior margin straight, neither emarginate nor step-like; labrum not emarginate or minimally emarginate apically; occipital carina continuous ventrally, not joining hypostomal carina, mostly not expanded but expanded in A. weiri , in many A. caliginosus , and slightly so ventrally in A. amblygnathus ; hypostomal carina not expanded; gena narrow in dorsal view (e.g., Fig. 31 ), somewhat thicker in A. solitarius ; scutum without notauli; scutellum not foveate along anterior margin except slightly foveate in A. carinatus and A. solitarius ; postspiracular carina present, about as long as midocellar diameter (about twice as long as midocellar diameter in A. solitarius ); propleuron and forecoxal venter closely punctate; metapleuron not ridged longitudinally between dorsal and ventral metapleural pits except ridged in A. weiri and most A. caliginosus ; metapleural flange narrowly lamelliform; propodeal dorsum with median longitudinal carina; forewing with two or three submarginal cells; first recurrent vein received by submarginal cell I or interstitial with first intersubmarginal vein; marginal cell acuminate; midcoxae separated, hindcoxae contiguous; punctures of tergum I well defined; sterna without graduli, punctate throughout; setae silvery, appressed to suberect on tergum I, at most slightly shorter than midocellar diameter; female tergum VI without pygidial plate; male flagellomeres cylindrical, not emarginate nor expanded, and without tyli except tyli present in A. rennellensis ; posterior margin of male sternum VIII emarginate.

GEOGRAPHIC DISTRIBUTION.— Four species of Aulacophilinus inhabit Australia ( A. caliginosus , A. mandibulatus , A. pyrrhicus , and A. weiri ), four other occur in New Guinea ( A. amblygnathus , A. carinatus , A. solitarius , and A. tegularis ), and A. rennellensis is found on the Rennell Island in the Solomon Archipelago. Of the four Australian species, A. caliginosus is known from all parts of the continent including Tasmania, A. mandibulatum occurs in the South Australia and Western Australia, and A. pyrrhicum and A. weiri are found in the Northern Territory and Queensland.

CLADISTIC ANALYSIS

The following is the list of characters used in the analysis below:

1. Clypeal lamella: 0. present, 1. absent.

2. Mandible surface: 0. partly impunctate, 1. punctate throughout on both inner and outer surface.

3. Mandible: acetabular and condylar groves: 1. grooves present, 2. grooves absent.

4. Mandible: apex: 0. acuminate, 1. broadly truncate.

5. Mandible: color: 0. black, 1. ferruginous

6. Width of labrum: 0. more than one midocellar diameter, 1. less than one midocellar diameter

7. Sculpture of frons, vertex, scutum, and mesopleuron: 0. punctate, 1. areolate.

8. Crenulate sulcus on gena: 0. absent, 1. present.

9. Tegula: 0. impunctate posteriorly, 1. punctate throughout.

10. Omalus: 0. absent, 1. present.

11. Number of submarginal cells: 0. three, 1. two.

12. Gaster: shape: 1. sessile, 2. pedunculate.

13. Gaster: color: 0. black,1. ferruginous

14. Apical emargination of male sternum VIII: 0. shallow or moderately deep, 1. prominently deep.

Pison atrum Spinola , the type species of Pison , was used as the outgroup, and the following data matrix was constructed:

Pison atrum 00000 00000 0000

amblygnathus 11110 00000 0000

caliginosus 11110 10010 1001

carinatus 11110 00000 0000

mandibulatus 11111 10010 0000

pyrrhicus 11110 00100 0010

rennellensis 11110 10000 1100

solitarius 11110 00000 000?

tegularis 11110 00010 000?

weiri 11110 11111 1001

A cladistic analysis was kindly performed by Fernando Alvarez Padilla of the Universidad Nacional Autónoma de México through implicit enumeration, using T.N.T. program by Pablo Goloboff, Steve Farris, and Kevin Nixon (2003). One tree of 16 steps was found ( Fig. 1 ), with the consistency index of 87 and the retention index of 80 (several nodes on the cladogram are without support because there are no characters that can be optimized unambiguously at those nodes).

Key to Species

1. Forewing with two submarginal cells in each wing (with one submarginal cell in occasional specimens)................................................................. 2

– Forewing with three submarginal cells........................................... 4

2. Gaster conspicuously pedunculate ( Figs. 37 , 38), its length 3.0–3.5 × its maximum width, conspicuously swollen apically ( Fig. 38 ); tegula impunctate in posterior half; outer surface of hindtibia without spines; dorsal length of flagellomere I 2.5 × its apical length in female, 2.4 × in male. Solomon Islands................................ rennellensis Lomholdt , p. 00

– Gaster sessile (its length about equal to maximum width), not swollen apically; tegula minutely punctate throughout; outer surface of hindtibia with fine but well-defined spines; dorsal length of flagellomere I 1.4–2.0 × its apical length in female, 1.3–1.9 × in male................ 3

3. Frons, vertex, scutum, and mesopleuron areolate; gena with well-defined, crenulate sulcus along posterior eye margin, sulcus delimited posteriorly by well-defined carina; pronotal collar with well-defined, crenulate furrow; omalus present. Australia............ weiri Naumann , p. 00

– Frons: vertex, scutum, and mesopleuron punctate (mesopleuron rugose in some specimens); gena without sulcus and carina along posterior eye margin; pronotal collar without crenulate furrow; omalus absent. Australia, Norfolk Island................... caliginosus Turner , p. 00

4. Gaster and at least tibiae ferruginous; gena with crenulate sulcus along posterior eye margin, sulcus delimited posteriorly by well-defined carina; posterior propodeal surface with several ridges radiating up from gastropropodeal articulation. Australia......... pyrrhicus Naumann , p. 00

– Gaster and legs black; gena without crenulate sulcus and carina along posterior eye margin; posterior propodeal surface without ridges radiating up from gastropropodeal articulation..... 5

5. Mandible ferruginous; tegula finely punctate throughout. Australia. mandibulatus Turner , p. 00 Mandible black; tegula punctate throughout or impunctate posteriorly.................. 6

6. Punctures of frons 2–3 diameters apart, on scutum more than one diameter apart at least at center; setae on frons erect, about as long as midocellar diameter, on scutum erect, about 0.5 × as long as midocellar diameter. New Guinea................... amblygnathus Menke , p. 00

– Punctures of frons and scutum averaging no more than one diameter apart; setae on frons suberect, about as long as 0.5–0.7 × midocellar diameter, on scutum suberect, about 0.3 × as long as midocellar diameter.................................................... 7

7. Tegula evenly punctate throughout. New Guinea......... tegularis Pulawski , sp. nov., p. 00

– Tegula impunctate posteriorly or with evanescent, microscopic punctures (punctures markedly smaller than those in anterior part).............................................. 8

8. Propodeum with well-defined carina between side and dorsum and posterior surface, on dorsum laterally with well-defined, short, transverse ridges meeting carina. New Guinea........................................................... carinatus Pulawski , sp. nov., p. 00

– Propodeum without carina between side and dorsum and posterior surface, on dorsum laterally with evanescent ridges. New Guinea.................. solitarius Pulawski , sp. nov., p. 00

Figures

FIGURES 2–8. Aulacophilus amblygnathus Menke. (2) Clypeus and mandibles, female; (3) Upper frons, female; (4) Clypeus and mandibles, male; (5) Upper frons, male; (6) Sternum VIII, ventral surface, male; (7) Genitalia, dorsal view, male; (8) Genitalia, lateral view, male.

FIGURES 30–36. Aulacophilus pyrrhicus. (30) Female clypeus and mandibles; (31) Female head in dorsal view; (32) Female tegula and adjacent portion of scutum; (33) Male sternum VIII (ventral surface); (34) Male sternum VIII in lateral view; (35) Male genitalia dorsally; (36) Male genitalia laterally.

FIGURE 1. Phylogenetic tree of Aulacophilinus

FIGURE 37. Collecting localities of Aulacophilinus pyrrhicus.

FIGURES 38–40. Aulacophilinus rennellensis. (38) Female clypeus and mandibles; (39) Male clypeus and mandibles; (40) Female head dorsally.