Xanthonia hirsuta Weisman, 2019

Riley, Edward G., Weisman, Donald M. & Quinn, Michael A., 2019, A taxonomic review of the Xanthonia species occurring in Texas (Coleoptera: Chrysomelidae, Eumolpinae), Zootaxa 4668 (1), pp. 1-29 : 12-14

7. Xanthonia hirsuta Weisman , n. sp.

( Figs 12 , 24 , 45–46 , 57 , 62 ; Map 3 )

Holotype. Here designated, ♂ ( Fig 57 ) with the following labels and attachment: || Dallas TX | IV-5-12. || WDPierce | Collector || on | Juniperus | sp. || NM || 141 || [glycerin-filled microvial containing male genitalia] || [red label] HO- LOTYPE | Xanthonia | hirsuta | Weisman ||. This specimen is dissected with the abdomen glued on its point and the median lobe contained in a glycerine-filled microvial, all appendages intact. Deposited in USNM.

Paratypes. (12 total), TEXAS: Dallas Co., Dallas , IV-25-1907, Schwarz and Pratt [5 USNM, 1 male dissected with microvial] ; same locality, IV-5-1912, W. D. Peirce, on Juniperus [1 USNM] ; same data, except IV-27-1912 [2 USNM] ; same locality, III-2-1908, E. S. Tucker, on pine [3 USNM, 1 male dissected with microvial] ; same locality, III-6-1909, E. S. Tucker [1 USNM] .

Diagnosis. Size moderate, length 3.0– 3.5 mm; ground color dark brown, elytra with consistent pattern of black maculae ( Figs 12 , 57 ), venter of body black; hairs of elytra generally dense, composed of single rows of strongly reclined hairs on intervals and equally long appressed hairs arising from punctures; ventral tooth of profemur minute; lateral margins of all ventrites entire; median lobe of male genitalia narrowed distally, apex evenly rounded with narrow parallel-sided incision ( Fig 45 ).

Description. Color: Head reddish brown, labrum and basal segments of antennae yellowish brown, distal segments reddish brown. Pronotum uniformly dark reddish brown. Elytra dark reddish brown with darker spot at middle of base and each elytron with two or three dark longitudinal lines on disc, uniting basally and formed by extension and fusion of subapical spots, elytral markings partially obscured by dense pubescence ( Figs 12 , 57 ). Venter dark brown with distal abdominal ventrites lighter. Legs uniformly yellowish brown. Form: Length 3.0– 3.5 mm Head densely and coarsely punctate throughout and with long golden recumbent pubescence, face with median line not evident, inter-antennal area flat. Pronotum densely and coarsely punctate, with long silky golden recumbent pubescence, length averaging 1.35 times its width, widest behind middle; sides fairly evenly broadly rounded in dorsal aspect; anterior transverse depression and lateral impressions absent. Elytra length averaging 1.45 times combined width, 2.45 times length of pronotum; basal callosity evident; punctures in regular rows, confused near scutellum, behind sulcus and below humerus; punctures as large as or larger than intervals of disc; intervals flat, or slightly elevated at sides and apex; pubescence composed of strongly reclined or recumbent hairs in single lines on the intervals and appressed hairs arising from punctures as long as the reclined hairs, pubescence fairly dense partially obscuring punctation. Metasternum with lateral areas rugose and very coarsely densely punctate, becoming smooth toward midline. Abdomen with ridge on lateral margins of all ventrites entire, last ventrite of male flat without tubercles. Ventral tooth on all femora minute to absent. Median lobe of male genitalia in en-face view narrowed distally, apex evenly rounded with narrow parallel-sided incision ( Figs 45–46 ).

Range. Colorado, New Mexico and Texas. Primarily on the Edwards Plateau and westward to the Davis Mountains, Chisos Mountains and Guadalupe Mountains in Texas ( Map 3 ), southeastern New Mexico, and extreme southeastern Colorado (Baca County).

Plant associations. Weisman (1960) cited plant associations from label data of “on Juniperus ” and “on Pine.” More recently-collected specimens are mostly from Juniperus , represented by many separate collections. Of the 380 specimens tabulated for the Travis County study, 99% were from Juniperus ashei J. Buchholz (Table 1). The Austin County specimens, representing the eastern-most portion of the range, were collected from J. virginiana L.

Seasonal distribution. Most collections of this species are from the early spring through early June, but some are from the fall and winter months, indicating that unlike other Texas Xanthonia species, at least some emergence occurs prior to the spring warming. During the Travis County study, more specimens were taken during March than during subsequent months ( Figure 62 ).

Remarks. This is a distinctive and easily recognized species, separated from the others occurring in the United States by the longer and denser elytral pubescence. That on the elytra is all decumbent, laying close to the elytral surface, and the hairs arising from the punctures are as long as those arising from the intervals. It is clearly a Juniperus specialist, but not closely related to the other juniper-associated species ( X. vagans and X. marquai ).

Specimens examined. See Appendix 5. The genitalia of 27 males from 15 localities were examined.

Figures

FIGURES 10–12. Xanthonia species, dorsal habitus. 10) X. vagans (Cochise Co., Arizona); 11) X. marquai (Jeff Davis Co., Texas); 12) X. hirsuta (Travis Co., Texas). Scale bars = 1 mm. Figs 13–16. Xanthonia species, types and type labels. 13) X. vagans (courtesy of the MCZ type database); 14) X. marquai; 15) X. picturata; 16) X. villosula.

FIGURES 17–26. Xanthonia species, margins of ventrites III–V. 17) X. dentata; 18) X. parva; 19) X. villosula; 20) X. angulata. Figs. 21–22. Xanthonia species, profemora. 21) X. vagans; 22) X. marquai; 23) X. picturata; 24) X. hirsuta; 25) X. texana; 26) X. parva.

FIGURES 27–54. Xanthonia species, en-face and lateral view of median lobe. 27) X. vagans (Palmerlee, Arizona); 28–29) X. vagans (Chisos Mts., Texas); 30–31) X. marquai (Jeff Davis Co., Texas); 32–33) X. picturata (Gonzales, Texas); 34–35) X. parva (Kerr Co., Texas); 36) X. villosula (Miller, Indiana); 37) X. villosula (Dallas, Texas); 38–39) X. villosula (Natchez, Mississippi); 40) X. dentata (Socorro Co., New Mexico); 41) X. dentata (Sapello, New Mexico); 42) X. dentata (Chisos Mts., Texas); 43–44) X. dentata (Cloudcroft, New Mexico); 45–46) X. hirsuta (Dallas, Texas); 47–49) X. texana (Victoria, Texas); 50) X. nitida (San Antonio, Texas); 51–52) X. nitida (Dallas, Texas); 53–54) X. querci (Dallas, Texas). All figures from Weisman (1960), except 30–31 and 32–33.

FIGURES 55–60. Xanthonia species, types and type labels. 55) X. dentata; 56) X. parva; 57) X. hirsuta; 58) X. angulata; 59) X. striata, 60) X. nitida.

FIGURES 61–63. Seasonal distribution of Xanthonia species from Travis County, Texas (data from Quinn, 2000). 61) X. picturata; 62) X. hirsuta; 63) X. texana. Table 1. Quantitative plant association data for Xanthonia species from Travis County, Texas (data from Quinn, 2000)

MAPS 1–6. Distribution of Xanthonia species. 1) X. vagans; 2) X. furcata (■), X. marquai (♦), X. nitida (●); 3) X. hirsuta; 4) X. picturata; 5) X. angulata (♦), X. dentata (●), X. querci (■); 6) X. parva (■), X. villosula (●).