Phyllophaga (Phyllophaga) gramma Morón and Woodruff, 2014

Morón, Miguel-Ángel & Woodruff, Robert E., 2014, New Species of Phyllophaga Harris (Coleoptera: Scarabaeidae: Melolonthinae) from northeastern Mexico., Insecta Mundi 2014 (328), pp. 1-9 : 2-4

Phyllophaga (Phyllophaga) gramma Morón and Woodruff , new species

( Figures 1-8 )

Description. Holotype male. Total body length: 11.7 mm. Humeral width: 5.0 mm. Head and pronotum shiny, dark reddish brown; elytra velvety reddish brown; abdomen and legs shiny yellowish brown. Clypeus with scattered erect short setae, 2.4 times wider than long, anterior border strongly elevated, anterior margin broadly curved, disk surface nearly flattened, briefly rising at middle, densely covered with round punctures. Frontoclypeal suture clearly impressed, sinuate at middle. Frons 2.8 times wider than long, broadly convex, rugo-punctate with sparse medium sized erect setae on disk.

Antenna with 9-antennomeres and 3- lamellate club, lamellae 2.2 times longer than length of preceding 5 antennomeres combined; antennomeres 3 and 4 each same length, antennomere 5 as long as preceding 2; antennomere 6 much shorter than 5 with acute prominence on anterior side. Frons 4.8 times wider than dorsal diameter of eye. Eye canthus long, narrow, with 12 setae ( Fig. 1 ). Labrum reniform, slightly concave, with scattered setae along borders. Mentum nearly flat, with scarce punctures and slender setae at sides, anterior border briefly sinuate.

Pronotum 1.7 times wider than long and 2.4 times wider than frons. Pronotal disk with many erect, slender setae and round punctures irregularly separated by 1-4 diameters; anterior bead complete, with long, slender setae; lateral borders broadly angled, lateral marginal bead weakly crenulate, with slender, long setae; basal bead indicated by regular row of punctures, with long setae near middle; anterior angles slightly obtuse, rounded; posterior angles broadly obtuse, weakly prominent ( Fig. 1 ).

Scutellum 1.4 times wider than long, without punctures; anterior border broadly sinuate, with many long setae.

Elytron 2.3 times longer than wide, pruinose, with setiferous punctures densely and irregularly distributed on disk; a group of erect, long setae around scutellum, and scattered short setae near the apex; epipleural border progressively narrowed toward apex, with fringe of long setae; humeral callus rounded, prominent; apical callus rounded. Metathoracic wings completely developed.

Pterosternum with many yellowish, long setae. Visible abdominal sternites 2 to 5 with white pruinosity and scattered yellow setae at sides, shallowly depressed at middle; anal plate short, narrow, with weak transverse keel near basal margin and brief depression at middle, and scattered long setae along posterior border.

Propygidium dull, densely punctuate, with many short setae. Pygidium shiny, widely convex, with numerous, shallow punctures, and medium sized setae, regularly distributed; apical margin with 14 slender setae; basal margin narrow, not distinct at middle.

Protibia slightly shorter than protarsus (0.9:1), with 2 large teeth and a basal small tooth on external border, preapical spur acute, straight, shorter than 2nd protarsomere. Mesotibia with an oblique, well-marked, setiferous carina and small setiferous teeth on external side; upper apical spur with acute apex, as long as lower spur. Metatibia slightly shorter than metatarsus (0.9:1), with an oblique setiferous carina and small setiferous tooth on external side; upper apical spur articulated, slightly curved, apex rounded, nearly as long as basal metatarsomere, and 1.3 times longer than lower spur; lower apical spur articulated, nearly straight, apex rounded. Protarsomeres 1-4 semicylindrical elongate with enlarged apex, with scattered ventral setae and crown of apical setae. Meso- and meta- tarsomeres semicylindrical, elongate, with enlarged apex, crown of apical setae, and 2 rows of setae along ventral side. Tarsal claws dentate, with ventral tooth small, acute, located toward base ( Fig. 3 ).

Genital capsule with short, widened, curved parameres fused dorsally and ventrally, apex with 2 small rounded teeth ( Fig. 4, 6-8 ). Aedeagus with poorly sclerotized tube- like support; inner sac with apical sclerotized claw and many latero-ventral minute spines ( Fig. 6-8 ). Tectum wide, uniformly convex. Length of genital capsule from apex of parameres to border of basal piece: 3.4 mm.

Allotype female. Similar to male except as follows: total body length: 14.5 mm. Humeral width: 5.4 mm.; antennal club as long as preceding 5 antennomeres combined ( Fig. 2 ); head and pronotal punctuation deeper. Visible abdominal sternites 2 to 4 convex, with scattered, short setae near midline; sternite 5 enlarged, with many punctures and long setae; anal plate short, widely convex, with shallow punctures and slender setae. Both apical spurs of metatibia widened, curved, with rounded apices. Ventral genital plates sclerotized, short, nearly symmetrical, broadly convex, with rounded distal border, each with 1 apical seta; dorsal genital plates not fused, large, with distal border slightly angled, with 3-4 apical setae ( Fig. 5 ).

Variation. Body varies from 11.4 mm to 14.6 mm in length and 4.9 to 5.5 mm in humeral width.

Type Series. (Described from 38 males and 11 females). Holotype male; MEXICO: Nuevo Leon, 7 km sur Monterrey , 17-II-1962, on gramma flying close to ground, J. Mathieu ( FSCA) . Paratypes (37 males, 11 females): same data as holotype, (10 males, 1 female FSCA; 4 males IEXA; 2 males MXAL) ; same data except 17-II-1967 (4 males IEXA). Nuevo Leon, 4 km S Galeana , 13-V-1961, J. Mathieu (1 male, FSCA) ; Nuevo Leon, El Cercado, 11-III-1967, J. Mathieu (8 males FSCA) ; Nuevo Leon, Cañón de Iturbide , 30- VII-1969, on Rhus pachyrhachis, J. Mathieu and M. W. Sanderson (1 female FSCA) ; Nuevo Leon, Cañón de Iturbide , 8-VII-1969, black light trap, M. W. Sanderson, J. Mathieu and D. Cadena (1 male FSCA). Nuevo Leon, Santiago, San Francisco, 22-IV- 1989, 540 m, luz, N. Celestino (3 pairs MXAL; 2 pairs CMNC; 2 pairs CNIN, 2 females IEXA) .

Type Locality. Parque Nacional Cumbres de Monterrey , Monterrey municipality, state of Nuevo Leon, Mexico (25°36' 49”N; 100° 18' 29” W) .

Biological Data. Apparently this species only inhabits grasslands and open pine-oak forests located at 500-600 m of elevation in the northern slopes of Cumbres de Monterrey, on the road to Villa de Santiago and south of Galeana. Specimens studied were collected during February (22), March (8), April (16), May (1) and July (2), but most of the males were taken at dusk during February flying close to ground over short tall grass (gramma), apparently searching for females hidden between soil and grass. One female was collected feeding on leaves of Rhus pachyrhachis Hemsl. (Anacardiaceae) . All the specimens from Santiago were attracted by electric lights during April. The date of capture of many specimens, mainly from south of Monterrey city, is very early in comparison with the usual phenology of the genus in Central Mexico (May-July).

Remarks. Phyllophaga gramma is similar to the species group “anodentata” as defined by Morón (1986), but has the antennae with 9, rather than 10, antennomeres, and the structure of the male anal plate is very simple, nearly convex, without tooth-like projection on the basal border. The ring- shaped parameres are as in other members of this group, but details in the form of apical border and ventral teeth, as well as the shape and microstructures of the aedeagus, are clearly different from other species.

Etymology. We recognize the early studies on this species, giving the same name proposed on labels by Sanderson and Mathieu, gramma , in reference to its habits on the short grasses, so called grama, Spanish name with Latin root (gramen, graminis, gramineus; Jaeger, 1955) applied to many species of wild and cultivated grasses in Mexico.

Figures

Figures 1-8. Phyllophaga gramma. 1) Head and pronotum. 2) Female antenna. 3) Male fore tarsal claw. 4) Parameres, ventral view. 5) Female genital plates, ventral view. 6) Genital capsule with extended aedeagus, lateral view. 7) Parameres and aedeagus, distal view. 8) Genital capsule, dorsal view. Scale lines = 1 mm, except in Fig.3 = 0.5 mm.