Pseudopectinosoma Katovich, 2011

Katovich, Kerry, 2011, PseudopectinosomaKatovich, New Genus, and Review ofPectinosomaArrow (Scarabaeidae: Melolonthinae: Macrodactylini), The Coleopterists Bulletin 65 (4), pp. 335-340 : 335-340

Pseudopectinosoma Katovich , new genus

Type Species. Pseudopectinosoma mesa Katovich , new species (present designation), deposited at the CMNC.

Diagnosis. This genus is characterized by its elongate body and large size in comparison to other macrodactylines; prementum elongate, ventral surface with a medial groove; mesosternum trapezoidal, flattened, anteriorly obscured in males by a posteriorly produced prothoracic process; sixth ventrite of males with a raised process; all pretarsal claws simple in both sexes, a character unique to all other macrodactylines except male Pectinosoma . Males and females are sexually dimorphic, with females lacking abdominal processes. Pseudopectinosoma may be distinguished from Pectinosoma and Ancistrosoma by the following characteristics. Males of all three genera possess an abdominal process, but the location varies. In Ancistrosoma , the process arises on the posterior margin of the first ventrite, whereas in Pectinosoma the process arises from the medial region of the fifth ventrite and from the sixth ventrite in Pseudopectinosoma . The obvious sixth visible ventrite is itself unusual, as most melolonthines have a reduced or partially visible sixth ventrite that is often partially concealed by the pygidium.

Description. General form elongate, narrow. Head: Clypeus not coplanar with frons, prementum

335

elongate, ventral surface with medial groove. Pronotum: Oblong, hexagonal, longer than wide, widest medially, anterior angle acute, posterior angle acutely toothed, posterior margin medially tridentate; prosternum of male with blade-shaped, posteriorly facing process that extends partially over the mesosternum; prothoracic legs with transverse coxae, similar to males of Pectinosoma , but differing from Ancistrosoma (elongate coxae); pretarsus with claws not divergent, equal in length, claws simple in males, split in females, empodium elongate, narrow, bisetose. Mesothorax: Mesosternum trapezoidal, flattened, anteriorly obscured in males by blade-shaped, posteriorly-facing process (process present in Pectinosoma and Ancistrosoma males, but differing in design); scutellum cordate, appearing divided; elytra longer than wide, widest in anterior one-fourth, anterior umbones prominent, posterior umbone weakly developed; pretarsus similar to prothoracic pretarsus. Metathorax: Metathoracic coxae widely separated; pretarsus with claws and empodium similar to prothoracic and mesothoracic claws. Abdomen: Six visible ventrites, sixth ventrite of male medially with a raised process (differing from process on the first ventrite of male Ancistrosoma and fifth ventrite of male Pectinosoma ), posterior margin membranous, ventrite and tergite of fifth abdominal segment (historically referred to as the propygidium if the sixth ventrite is partially covered by the pygidium) not separated by suture, spiracle placed anteriorly, fifth ventrite partially covered by elytra, not visible in dorsal view; pygidium cone-shaped in males, longer than wide, wrapping around ventrally.

Etymology. A false Pectinosoma .

Pseudopectinosoma mesa Katovich , new species ( Figs. 1, 2 , 5, 6 , 9, 10 , 13, 14 , 17, 18)

Diagnosis. This species is recognized by its elongate body, large size, brown body color with distinctive light brown patches on the pronotum and elytra; prosternum of males with a bladeshaped, posteriorly facing process ( Fig. 5 ); sixth ventrite of male with a posteriorly raised, prominent, mesa-like process ( Fig. 6 ).

Material Examined. Holotype male, first label, Colombia, Putumayo, Pto. Umbria, Belle – legrt, Coll. Martinez; underside of first label, Ene – 980; second label H & A Howden Collection, ex. A. Martinez coll; third label Pectinosoma Sp. Nov. A. Martinez det 1990. fourth label red , Holotype, Pseudopectinosoma mesa Katovich 2011 . Holotype deposited in CMNC . Paratype, male, first label, white, Parandra Gigante : Huila, Caquete, Colombia VI-81; underside of first label, July 27, 1981, O. Rojes coll.; second label, white, paratype Pseudo- pectinosoma mesa Katovich 2011 . Specimen deposited in PKLC . Allotype, female, first label, small, white, Gigante Huila, Caquete Colombia, VI/27 /80; second label, white , Allotype female, Pseudopectinosoma mesa Katovich 2011 . Specimen deposited in PKLC .

Description of Male. Measurements (n = 2): Anterior ocular margin 2.0 mm; prothorax at apex 4.5 mm, at widest point 8.0 mm, elytra at base 6.8 mm, at widest point 9.0 mm, at declivity of elytral base 4.5 mm; total length 24.0 mm. Color and vestiture: Head, pronotum, abdomen, and elytra brown, patches on pronotum and elytra light

Figs. 17–20. 17–18) Pseudopectinosoma mesa , male, median lobe and parameres, caudal and lateral views; 19–20) Pectinosoma elongatum , male, median lobe and parameres, caudal and lateral views.

brown, femora dark brown, tibiae and tarsi mottled brown, abdomen with fine yellow setae. Head: Clypeus not coplanar with frons, clypeal suture incomplete; frons angled at 30° in relation to clypeus; labrum in frontal profile trapezoidal, emarginate, not coplanar with clypeus; labium with prementum elongate, ventral surface with medial groove; mandibles in dorsal profile rectangular, thin in lateral profile, scissoral area membranous, emarginate, directed aborally, molar area produced aborally, well-sclerotized, composed of numerous plates; maxillae with basistipes rectangular, aboral margin deeply grooved, dististipes broadly triangular, aboral lateral margin grooved; galea with 6 well-developed teeth, teeth oriented adorally at 60°; lacinia triangular, tightly conforming with dististipes; maxillary palpi 4-segmented, with apical palpus ovate, equal to segment 2; antenna 9-segmented, segment 1 equal to length of segment 5, segments 2–4 equal in length, segments 7–9 forming club, club segments equal in length to segments 4–6 combined. Prothorax: Pronotum ( Fig. 9 ) oblong, hexagonal, longer than wide, widest medially, anterior angle acute, lateral margin convex, margin with slight shelf in anterior third, posterior angle acutely toothed, posterior margin weakly convex, medially tridentate; prosternum ( Fig. 5 ) with blade-shaped, posteriorly facing process that extends partially over the mesosternum; prothoracic legs with transverse coxae; tibia subequal in width to femur, bidentate in distal half; pretarsus of proleg with claws not divergent, equal in length and simple, empodium elongate, narrow, bisetose. Mesothorax: Mesosternum trapezoidal, flattened, anteriorly obscured by blade-shaped, posteriorly facing prosternal process; scutellum cordate, appearing weakly divided; elytra ( Fig. 10 ) longer than wide, widest in anterior fourth, epipleuron with slightly deflexed margin and narrow membrane along margin, elytral surface with pair of weak striae, dorsal surface distinctly flattened, anterior umbones prominent, posterior umbones weakly developed; pretarsus of midleg similar to that of proleg. Metathorax: Metathoracic coxae widely separated; leg with femur ovate, widest in distal fourth; tibiae clavate, narrow proximally; posteroventral margin with pair of spurs, ventral spur short, broad, dorsal spur elongate, narrow, spurs raised above level of tarsal articulation joint, posterior margin with several elongate setae, margin with a deep, U-shaped groove; pretarsus of hind leg similar to those of proleg and midleg. Abdomen ( Fig. 6 ): Ventrites 1–4 subequal in width; ventrite 1 with raised sinuate anterior margin; width of fifth ventrite 2× width of ventrite 1, posterior margin medially concave, fused with tergite, spiracle placed anteriorly; width of sixth ventrite equal to width of first ventrite, medially with a raised, trapezoidal process with ventral surface flattened, posterior margin of ventrite membranous, in lateral view sixth ventrite partially concealed under the pygidium; pygidium conical, longer than wide, wrapping around ventrally. Genitalia: Parameres as in Figs. 17 and 18.

Description of Female. Measurements (n = 1): Anterior ocular margin 2.0 mm; prothorax at apex 4.0 mm, at widest point 6.0 mm, elytra at base 5.5 mm, at widest point 9.0 mm, at declivity of elytral base 3.5 mm; total length 22.0 mm. Color and vestiture: Head, pronotum ( Fig. 13 ), abdomen, and elytra ( Fig. 14 ) dark brown, patches on pronotum and elytra light brown, femora dark brown, tibiae and tarsi mottled brown, abdomen with fine yellow setae. In all other respects, the female is similar to the male, except that it lacks abdominal processes. The female’ s pygidium is sinuate on the posterior margin, indented medially on the dorsal surface, and is not conical or wraps around ventrally as in the male.

Distribution. This species is known only from Colombia.

Remarks. The immature stages of this species are unknown, as is its habitat.

Etymology. This species is named for the distinctively flat, table-like prominence on the male’ s sixth ventrite.

Figures

Figs. 1–4. 1–2) Pseudopectinosoma mesa, male, dorsal and lateral views; 3–4) Pectinosoma elongatum, male, dorsal and lateral views.

Figs. 5–8. 5) Pseudopectinosoma mesa, male, procoxae and pro- and mesosternum, ventral view; 6) P. mesa, male, visible abdominal segments, ventral view, membranous posterior margin of sixth ventrite shaded gray; 7) Pectinosoma elongatum, male, procoxae and pro- and mesosternum, ventral view; 8) P. elongatum male, visible abdominal segments, ventral view.

Figs. 9–12. 9) Pseudopectinosoma mesa, male, head and pronotum, dorsal view; 10) P. mesa, male, scutellum, elytra, and pygidium, dorsal view; 11) Pectinosoma elongatum, male, head and pronotum, dorsal view; 12) P. elongatum, male, scutellum, elytra, and pygidium, dorsal view.

Figs. 13–16. 13) Pseudopectinosoma mesa, female, head and pronotum, dorsal view; 14) P. mesa, female, scutellum, elytra, and pygidium, dorsal view; 15) Pectinosoma elongatum, female, head and pronotum, dorsal view; 16) P. elongatum, female, scutellum, elytra, and pygidium, dorsal view.