Neotriphyllus, Lawrence, John F., Escalona, Hermes E., Leschen, Richard A. B. & Ślipiński, Adam, 2014

Lawrence, John F., Escalona, Hermes E., Leschen, Richard A. B. & Ślipiński, Adam, 2014, Review of the genera of Mycetophagidae (Coleoptera: Tenebrionoidea) with descriptions of new genera and a world generic key, Zootaxa 3826 (1), pp. 195-229 : 197-199

Neotriphyllus gen. n.

( Figs 2 E–F, 5C–E, M)

Type species. Mycetophagus confusus Horn, 1878 .

Diagnosis. In the presence of a relatively distinct 3-segmented antennal club and lack of distinct puncture rows, this genus resembles Triphyllus , Triphyllina , Pseudotriphyllus and Nototriphyllus . It differs from all of these, however, in the absence of abdominal pore fields in the male and from the last three in the lack of a pubescent fovea on the male prosternum. It is probably most closely related to Mycetophagus , in which genus the type species was formerly included, but in addition to the antennal and elytral features mentioned above, Neotriphyllus differs from all Mycetophagus species in having a pubescent fovea on the frons of the male ( Figs 2 E, 5M).

Description. Total length 3.00– 4.25 mm. Body about 1.92–2.24 times as long as wide, slightly convex. Color usually yellowish-brown to dark reddish-brown, with a pattern of yellow maculae on elytra; vestiture of moderately long, dense, recumbent setae.

Head slightly declined, without posterior constriction; posterior end of head capsule with short median endocarina on each side of which is a large, shallow concavity. Eyes moderately well developed and protuberant, truncate anteriorly, coarsely facetted. Antennal insertions barely concealed from above by weak frontal ridges. Frons in male with circular pubescent fovea just behind frontoclypeal suture, which is distinctly impressed and very slightly curved ( Figs 2 E, 5M); clypeus about 0.4 times as long as wide at base; sides converging anteriorly; anterior edge truncate. Labrum less than half as long as wide; sides slightly curved; anterior edge subtruncate. Antennae 11-segmented, with distinct but relatively narrow, 3-segmented club; scape only slightly longer than pedicel; antennomeres 3–8 at least slightly longer than wide; antennomeres 9 and 10 slightly transverse, subcylindrical and slightly expanded apically, with limited sensory area at apex ( Fig. 2 F); antennomere 11 narrowly rounded at apex with sensory area occupying about half its length. Mandibles about 1.3 times as long as wide, strongly but evenly curved apically, with two apical, acute teeth, differing slightly in length and aligned perpendicular to plane of movement of mandible; cutting edge on right mandible with stout tooth; molae strongly asymmetrical, transversely ridged; prostheca extensive and setose. Maxilla with galea expanded, broadly rounded and setose; lacinia slender and apically setose, without uncus; apical maxillary palpomere more or less cylindrical with obliquely truncate apex. Mentum about half as long as wide, apically expanded and truncate at apex; ligula laterally expanded and truncate; apical labial palpomere cylindrical. Submentum separated by suture from pregular area. Gula about half as long as wide; sutures strongly converging anteriorly. Corpotentorium strongly doubly arched, without anterior median process. Cervical sclerites small and slender.

Pronotum about 0.50–0.60 times as long as wide, widest at or near base, which is not narrower than combined elytral bases; sides weakly rounded; anterior edge truncate and finely margined; lateral carinae complete, smooth and finely margined; anterior angles not produced forward; posterior angles slightly obtuse and more or less rounded; posterior edge straight at sides and weakly trisinuate at middle; disc slightly convex with small, relatively weak, paired basal pits. Prosternum in front of coxae about as long as mid length of coxal cavity, strongly convex, without median pubescent fovea in male; anterior edge truncate. Prosternal process slightly expanded apically, distinctly curved dorsally behind coxae, slightly overlapping mesoventrite; apex subtruncate in ventral view. Notosternal suture complete. Procoxae not projecting below prosternum, without long concealed lateral extension. Trochantins fused to notum, not or barely exposed. Procoxal cavities slightly transverse, with short, narrow lateral extensions; externally moderately broadly open (postcoxal process short and blunt); internally barely open but with sternal and notal processes almost meeting.

Scutellar shield well developed, not abruptly elevated, about half as long as wide; sides slightly expanded near base, then continuous with broadly rounded apex. Elytra about 1.50–1.76 times as long as combined width and 3.08–3.82 times as long as pronotum, with about 10 fine and somewhat irregular rows of punctures, which are not easily visible due to scattered minute punctures bearing moderately long, recumbent setae; epipleuron narrow and incomplete; internal surface of each elytron with elongate, subsutural binding patch at apical third and sublateral binding patches at anterior fourth and middle. Mesoventrite separated by complete sutures from mesanepisterna, anterior edge on same plane as metaventrite, with small, median semicircular prosternal rest; body of ventrite slightly concave in middle. Mesocoxae slightly, obliquely transverse and weakly projecting, with exposed trochantins. Mesocoxal cavities at middle moderately narrowly separated (distance between them about a third as great as shortest diameter of one cavity); open laterally (partly closed by mesepimera). Mesometaventral junction dicondylic, with two very small mesoventral knobs fitting into paired impressions in the metaventral process. Metaventrite moderately convex; discrimen about 0.8 times as long as ventrite excluding anterior process. Exposed portion of metanepisternum about 3.3 times as long as wide; metepimeron visible. Metacoxae narrowly separated, not extending laterally to meet elytra. Metendosternite with long, narrow stalk, long lateral arms, well-developed laminae and anterior tendons located on arms at about middle. Hind wing about 2.5 times as long as wide; apical field about half total wing length, with two vaguely indicated radial extensions and a distinct post-radial sclerite; radial cell about twice as long as wide, with basal edge straight and inner posterobasal angle right; cross-vein r3 not apparent, possibly fused with r4, which is more or less complete; a curved oblique rod-like sclerite present next to r4; basal portion of RP moderately long; medial spur curved and reaching wing margin, where there is a slight medial embayment; medial field with four free veins, an oval, undivided medial binding patch and no wedge cell; anal lobe moderately well developed; anal embayment absent. Trochanterofemoral joint strongly oblique with femur narrowly reaching coxa. Tibiae relatively slender with weakly bipectinate spurs, those on protibia slightly unequal in length; tarsi 4-4- 4 in female and 3-4- 4 in male; tarsomere 1 distinctly longer than 2; pretarsal claws slender and simple.

Abdomen slightly longer than its basal width; ventrite 1 slightly shorter than 2, with acute intercoxal process; ventrite 5 strongly transverse and broadly rounded at apex. Abdominal tergites III–VI lightly sclerotized, V and VI with pair of large, circular wing-folding spicule patches; tergite VII more heavily sclerotized, 0.6 times as long as wide and broadly rounded at apex. Sternite VIII in male with short anterior strut (spiculum relictum), slightly emarginate at apex; tergite VIII lightly sclerotized and broadly rounded. Segment IX in male ( Fig. 5E ) with long, slender, slightly curved spiculum gastrale and moderately sclerotized laterotergites; segment X membranous. Aedeagus ( Fig. 5C ) with phallobase about 1.15 times as long as apicale, broadly rounded anteriorly; each paramere sinuate laterally, widest subapically and subacute at apex. Penis ( Fig. 5D ) almost as long as phallobase and apicale combined, slender and parallel-sided, subacute and ventrally curved at apex, with basal struts about one-fourth as long as body of penis. Sternite VIII in female with long, fixed, slender, slightly curved anterior strut (spiculum ventrale). Ovipositor about 3.3 times as long as wide, lightly sclerotized, except for baculi. Proctiger elongate with distinct baculi. Paraprocts subequal in length to gonocoxites, with distinct longitudinal baculi. Each coxite transversely divided into short, broad, proximal lobe with transverse basal baculum and a distal lobe twice as long, indistinctly, obliquely subdivided, narrowing apically, distinctly setose near apex and bearing long, slender, subapical, subcylindrical, gonostyli.

Etymology. From the Greek, neos, “new”, referring to the New World, and Triphyllus (a mycetophagid genus); gender masculine.

Distribution. Southwestern United States (Colorado, New Mexico, Arizona) south to Mexico, Guatemala and Costa Rica.

Biology. Adult Neotriphyllus confusus are found on the fruiting bodies of various saproxylic fungi including Ascomycota and Basidiomycota indicating that adults, at least, may not be host-specific.

Included species: N. confusus ( Horn, 1878) (Mycetophagus) comb. n. (= M. arizonensis Schaeffer, 1910 ) (synonymy by Parsons, 1975) (= Triphyllus perfectus Sharp, 1902: 638 ) syn. n. Parsons (1975) placed Mycetophagus confusus in the subgenus Gratusus Casey , based on the 3-segmented anennal club, although the antennal clubs in other Gratusus could hardly be considered as distinct; M. confusus also differed from other species in lacking seriate elytral punctation. None of these early workers noticed the distinct pubescent fovea on the male frons, which also occurs in males of Triphyllus perfectus Sharp , described from Mexico and Guatemala. A comparison of identified specimens of both species made it fairly obvious that a single species was distributed from Central America north to the southwestern United States, and that this species differed sufficiently from both Mycetophagus and Triphyllus to be placed in a separate genus.

Specimens examined. USA: AZ: Cochise Co.: Chiricahua Mts., West Turkey Creek, 5800 ft., 17.viii.1990, ex Lentinus lepidus, P. Skelley (4♂♂, 3♀♀, ANIC, NZAC); 5 mi. SW Portal, 4.viii.1961, Lot 899 JFL, Coriolus [= Trametes ] versicolor, J. F. Lawrence (1♀, ANIC). MEXICO: 7 mi. SE Temascaltepec, 6000 ft., 14.ix.1973, under pine bark, A. F. Newton (1♂, ANIC). GUATEMALA: Sacatepéquez: Finca San Rafael, 7200 ft., 27.vi.1948, on underside gilled fungi, CNHM Guatemala Zool. Exped. (1948), R. D. Mitchell (1♂, ANIC). COSTA RICA: Puntarenas: Monte Verde, 1450m, 25.v.1989, ex Schizopora paradoxa, J. Ashe, R. Brooks, R. Leschen, Snow Entomol. Mus. Costa Rica Exped., #472 (3♂♂, SEMC); Monte Verde, 1550m, 24.v.1989, ex Ganoderma, J. Ashe, R. Brooks, R. Leschen, Snow Entomol. Mus. Costa Rica Exped., #442 (3♂♂, 4♀♀, SEMC, NZAC); same locality, date & collectors, ex Xylaria, Snow Entomol. Mus. Costa Rica Exped., #421 (6♂♂, 5♀♀, SEMC, NZAC); same data (1♀, ANIC); Monte Verde, 1580m, 13.v.1989, ex various fungi, J. Ashe, R. Brooks, R. Leschen, Snow Entomol. Mus. Costa Rica Exped., #149 (1♂, SEMC); same locality, date & collectors, #148, ex Thelephoraceae (1♀, SEMC). HONDURAS: Francisco Morazán: El Rincon, 1.xii.1995, summit, closed forest, R. Turnbow (3♀♀, NZAC).

Figures

FIGURES 2 A – B, habitus, dorsal: A, Afrotyphaeola natalensis sp. n., length 1.6 mm; B, Thrimolus minutus Casey, length 1.2 mm. FIGURES 2 C – D, Litargus balteatus LeConte, prothoraces: C, dorsal, showing paired slit-like impressions; D, posterior, showing notal attachments of posterior apodemes and cryptopleura. Figure 2 E, Neotriphyllus confusus (Horn), head, dorsal. FIGURES 2 F – H, antennal apex: F, Neotriphyllus confusus (Horn); G, Pseudotriphyllus suturalis Reitter; H, Zeclaviger explanatus sp. n. Figure 2 I, Litargops sp. (Australia: ACT: Picadilly Circus, Brindabella Range), protibial apex. FIGURES 2 J – K, Litargus balteatus LeConte: J, labium; K, maxilla. All figures © CSIRO Australia.

FIGURES 5 A – H, mycetophagid male genitalia: A – B, Nototriphyllus araucania sp. n.: A, basale (phallobase) and apicale (partly fused parameres); B, penis; C – E, Neotriphyllus confusus (Horn): C, basale and apicale; D, penis; E, segments IX and X with long spiculum gastrale; F – H, Zeclaviger explanatus sp. n.: F, basale and apicale; G, penis; H, segments IX and X with short spiculum gastrale. FIGURES 5 I – J, habitus, dorsal: I, Nototriphyllus hispidellus (Broun), length 1.9 mm, © Landcare New Zealand; J, Filicivora chilensis (Philippi & Philippi), length 5.3 mm, © CSIRO Australia. FIGURES 5 K – L, Afrotyphaeola natalensis sp. n.: K, basale and apicale; L, penis. FIGURES 5 M – O, habitus: M, Neotriphyllus confusus (Horn), length 3.4 mm, © Landcare New Zealand; N, Nototriphyllus araucania sp. n., length 2.8 mm, © CSIRO Australia; O, Zeclaviger explanatus sp. n., length 1.6 mm, © Landcare New Zealand.