Xanthonia dentata Staines & Weisman, 2002

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 : 9-10

4. Xanthonia dentata Staines & Weisman

( Figs 2 , 17 , 40–44 , 55 ; Map 5 )

Xanthonia dentata Staines & Weisman, 2001b: 354 . Riley et al., 2003: 152.

Holotype. Examined, ♂ ( Fig 55 ) with labels and attachment as follows: || Cloudcroft | New Mex. | Wickham. || Wickham | collection | 1933 || ♂ || [glycerin-filled microvial containing male genitalia] || [red label] HOLOTYPE | XANTHONIA | DENTATA Staines & | Weisman | des. C. L. Staines 2000 ||. This specimen is dissected with abdo- men glued on point and male genitalia contained in a glycerin-filled microvial, all appendages intact. Conserved in USNM.

Diagnosis. Size moderate, length 2.8–3.4 mm; dorsal ground color dark reddish brown to medium brownish, elytra with distinct and fairly consistent pattern of black maculae ( Figs 2 , 55 ), venter dark brown to black; punctures of elytral disc irregular or with vague vestiges of rows present; elytral hairs composed of long erect hairs on intervals and appressed shorter hairs arising from punctures; ventral tooth of profemur small to minute; margins of ventrites III–V serrate to irregularly notched ( Fig 17 ); median lobe of male genitalia gradually tapered distally, apex narrowly rounded with short incision ( Fig 40–43 ).

Range. Arizona, Colorado, New Mexico and Texas. We have not confirmed the Kansas record reported by Staines & Weisman (2001b). Staines & Weisman (2001b) did not cite Arizona records for X. dentata , but a few specimens from Arizona were examined in the present study. Arizona records and an additional record for Colorado and records for New Mexico are cited herein (see Appendix 4). In Texas, the range of X. dentata is restricted to the mountains of the Trans-Pecos region ( Map 5 ).

Plant associations. This species has been regularly taken from oaks, including Quercus grisea Liebm.

Seasonal distribution. Collected from May to October, with most collections during June to August.

Remarks. Pale specimens of this species can be difficult to separate with certainty from X. pilosa Staines & Weisman , except by examination of the ridge on the margin of ventrites 3–5 and the male genitalia. In the later species, which is not presently known to occur in Texas, the ridge on the margins of ventrites 3–5 is entire. In general, the dorsal ground color of X. pilosa is a much lighter shade than that of X. dentata .

Specimens examined. See Appendix 3. The genitalia of 32 males from 18 localities were examined.

Figures

FIGURES 1–9. Xanthonia species, dorsal habitus. 1) X. angulata (Bastrop Co., Texas); 2) X. dentata (Jeff Davis Co., Texas); 3) X. furcata (Wood Co., Texas); 4) X. nitida (Pecos Co., Texas); 5) X. parva (Kerr Co., Texas); 6) X. picturata (Robertson Co., Texas); 7) X. querci (Val Verde Co., Texas); 8) X. texana (Bandera Co., Texas); 9) X. villosula (Bossier Parish, Louisiana). Images to scale, scale bar = 1 mm.

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.

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 (●).