Strumigenys mendezi, Booher, 2021

Booher, Douglas B., 2021, The ant genus Strumigenys Smith, 1860 (Hymenoptera: Formicidae) in western North America North of Mexico, Zootaxa 5061 (2), pp. 201-248 : 234-236

Strumigenys mendezi sp. nov.

Figure 40

Distribution. USA; Arizona

Holotype worker USA, Arizona, Cochise County, Chiricahua Mountains at the Jct. of Basin Trail #247 & Forest Service Road 42, 31°53.94’N 109° 14.27°W, 13 August 2009, 1890 m, Collector S. P. Cover, collection number 81600 (unique specimen identifier MCZ-ENT00584721) [ MCZC].

Paratype workers 2 workers, same collection as type (unique specimen identifier MCZ-ENT00584719, MCZ-ENT00584720) [ MCZC] .

Holotype and paratype worker measurements (n=3) HL = 0.64–0.719 (0.682); HW = 0.418 –0.451 (0.433); ML = 0.111 –0.131 (0.125); PW = 0.279 –0.315 (0.300); SL = 0.369 –0.381 (0.372); FL = 0.492 –0.513 (0.500); HT = 0.352 –0.375 (0.367); EL = 0.049 –0.067 (0.056); WL = 0.648 –0.741 (0.709); CI = 59.9–66.7 (63.6); MI = 16.1–20.5 (18.3); SI = 81.8–88.2 (86.0).

Diagnosis. Strumigenys mendezi is morphologically most similar to S. arizonica ( Ward, 1988) (sharing similar dentition, sculpturing, and most characters of pilosity) but can be most easily distinguished from S. arizonica by lack of flagellate pronotal humeral setae.

Description of worker. Mandible with a triangular basal lamella about as long as the base. Lamella followed by a short diastema that is about as long as length of first principle tooth. Mandible with five principle teeth. From base of mandible, first three and fifth tooth about equal in length with the fourth tooth obviously shorter. Principle teeth are followed by three sets of denticles decreasing in size with two large denticles, two intermediate sized denticles, and four minute denticles. Mandible terminating with small spiniform apical tooth for a total tooth count of 14. The first four principle teeth do not fully overlap when mandibles are fully closed and leave a zipperlike gap of open space between them. Labral lobes digitate and long, extending to third tooth in closed position, posterior half to apex of lobes with a series of projecting transparent spoon-shaped setae. Lateral to anterior free margins of clypeus broadly rounded and about 1.25 times as wide as long. In profile view head and clypeus nearly evenly flat with clypeus slightly raised above adjoining frontal area. Scape elongate SI 85. with a narrowly marginate anterior border. Propodeal teeth triangular and well formed with lamella of propodeal declivity narrowing below tooth followed by a broadly lamellate expansion above bulla of metapleural gland that is wider than propodeal tooth.

Pilosity. Setae on anterior margin of scape are spatulate with two or more setae curving towards base of scape at and posterior sub-basal bend. All setae extending from lateral and anterior margin of clypeus consist of spatulate curved setae that are directed anteriorly towards mandibles or to the midline. Clypeal dorsum covered with similar but shorter evenly distributed setae that curve anteriorly. Pilosity on dorsum of head, pronotum, and mesonotum consisting of more sparse but similar setae as on clypeal dorsum and are directed anteriorly or medially. Setae on dorsal nodes of petiole and post-petiole short simple arched setae directed posteriorly. Ground pilosity of gaster consisting of numerous short arched simple setae about as long as EL and mostly directed posteriorly. Differentiated subflagellate to flagellate setae limited to the basal quarter of the first gastral tergite, not present on head or body. Ground pilosity of legs short reclined to suberect simple setae. Outer surfaces of metatibia and basitarsi with a row of finer elongate setae that tend to recurve at midlength with apices resting against leg so that they appear looplike. However, on at least one metatibia in some specimens, one to two of these setae do not recurve and appear as elongate flagellate setae.

Sculpture. Dorsum of clypeus, head, mesosoma, and node of petiole densely covered with reticulopunctate sculpture as is the side of pronotum. Median carinal ridge on dorsum of pronotum lightly pronounced to absent. Meso- and metapleurae smooth and shining with peripherally reticulopunctate sculpture. Exposed disc of postpetiole smooth and shining. Basigastral costulae well developed but short, limited to the basal quarter of first gastral tergite mostly smooth and shining, but with some superficial punctuations present.

Spongiform appendages. Spongiform tissue well-developed and present as a ventral flange of the petiole, a lateral flange on node of petiole, as a flange surrounding the exposed disc of postpetiole, and as a ventral process of the postpetiole. Sub postpetiolar flange near the length of exposed portion of postpetiolar disc in profile.

Etymology. This species was discovered by Stefan Cover at The Ant Course (organized by Brian Fisher). Both Fisher and Cover expressed their wishes for this species to be named after Ray Mendez. Ray Mendez, an artist and myrmecological associate that has in many ways —over many years— provided his talents to help The Ant Course, a course instrumental to nearly all early career myrmecologists for the last 20 years. The name was created by adding the singular Latin genitive case suffix -i to the last name of a male person. The orthography of an eponym is unchangeable and does not depend on the generic name in which the epithet is used.

Comments. The morphologies of S. mendezi and S. arizonica are strikingly similar at first glance and both occur in Arizona, however they are ecologically dissimilar. Strumigenys arizonica is an obligate nest inhabitant of Trachymyrmex arizonensis where it benefits from the climate-controlled refuse chambers of their host and preys on Collembola associated with their host’s refuse (Gray al. 2018). Strumigenys mendezi appears to be a freely living ant species, not obligately associated with T. arizonensis or any other ants according to the collector Stefan Cover who discovered this species. He collected S. mendezi in a dense gray oak, juniper, emory oak woodland with vegetation height approximately 7.5 m, on a gentle southeastern facing slope. Individuals were collected by sifting litter under an oak stump in shade. I tentatively identify an alate queen as S. mendezi , based on images (BugGuide 2020b) (collection data: September 26, 2019, by Gary Alpert and Mark Szydlo 16 km southeast of Flagstaff in Walnut Canyon National Monument, Coconino County, Arizona, USA, 26 September 2019, Gary Alpert and Mark Szydlo).

Nontype material examined 3 workers, same collection as type (unique specimen identifier casent0747777, casent0747778, casent074779) [ MCZC] .

Nontype worker measurements. HL = 0.64–0.697 (0.659); HW = 0.418 –0.451 (0.431); ML = 0.123 –0.131 (0.127); PW = 0.279 –0.308 (0.291); SL = 0.369 –0.369 (0.369); EL = 0.049 –0.057 (0.053); WL = 0.648 –0.722 (0.693); CI = 64.7–66.7 (65.6); MI = 18.2–20.5 (19.3); SI = 81.8–88.2 (85.5).

Figures

FIGURE 40. Worker of Strumigenys mendezi [CAS: casent0179538]. Photographed by Erin Prado (AntWeb.org 2020).