SYSTEMATICS The Nearctic Genus Ammonaios Irwin and Lyneborg 1981 (Diptera: Therevidae) MARTIN HAUSER AND MICHAEL E. IRWIN University of Illinois and Illinois Natural History Survey, 1101 W. Peabody Drive, Urbana, IL 61801 Ann. Entomol. Soc. Am. 96(6): 738Ð765 (2003) Downloaded from https://academic.oup.com/aesa/article/96/6/738/14279 by guest on 22 September 2020 ABSTRACT The North American genus Ammonaios Irwin and Lyneborg is revised, and the three new species, A. confusus sp. n., A. mexicanus sp. n., and A. sabulosus sp. n., are described. The limits of the genus are redeÞned; a key to the species, descriptions of the pupae of three species, and distribution maps are provided. A cladistic analysis provides hypotheses of phylogenetic relationships within the genus, and the monophyly of Ammonaios was afÞrmed when tested with respect to species within its putatively closely related genera. KEY WORDS Ammonaios, Therevidae, new species, pupal morphology THIS ARTICLE IS PART of the effort to revise the species Specimens Examined Format. To conserve space of the genera of Nearctic Therevidae (Irwin and and include as much information as possible about Lyneborg 1981a, b; Webb and Irwin 1988, 1991a, b, c, each specimen, the “specimens examined” section un- 1995, 1999). In their revision of the Nearctic genera of der each species was formatted to avoid redundancy. Therevidae, Irwin and Lyneborg (1981a) erected the The data are reported hierarchically: country (all genus Ammonaios and designated Thereva nivea caps), state, county, populated place (with distance Kro¨ber as the type species. They stated that there are modiÞers, lower case), decimal degrees of latitude and “at least four additional, unnamed species at hand.” longitude [in square parentheses], altitude in meters Since then, several private collectors and institutions (m), collecting date (day, month in roman numbers, made more material available for study. Like most 4-digit year), collecting method (if known), collector members of the family Therevidae, the genus Ammon- (when represented by an acronym, see Appendix 1), aios prefers hot sandy habitats and is distributed in the number and sex of specimens followed by unique southwestern part of the United States and in north- identiÞer (all 6-digit numbers are MEI numbers if not western Mexico. The revision undertaken in this study stated otherwise), and collection depository acronym redeÞnes the limits of the genus, and provides a key to (all specimen numbers of specimens deposited in the the species, species descriptions with Þgures, descrip- same collection are enclosed by the same set of pa- tions of the pupae, and distribution maps. In a cladistic rentheses). Data not repeated in a series are the same analysis, the internal relationships of the genus Am- as those of preceding series. In the presentation of monaios were examined, and the monophyly of Am- locality data, a semicolon (;) terminates one series of monaios was afÞrmed with respect to species within its specimens and signals the beginning of the next. Ac- putatively closely related genera. ronyms of museums and collections are given in Ap- pendix 1; acronyms of collecters are in the Materials and Methods section. Immature Stages. The immature stages of Therevi- Materials and Methods dae are poorly known. Larvae are predators of imma- Specimens. A unique identifying number, usually a ture soil-dwelling insects. The larvae and pupae of three-letter preÞx followed by a 6-digit number species of Ammonaios can be found by sifting sand. (MEI######), was attached to each specimen (yel- Descriptions and biologies are available for very few low label). If a specimen had previously been assigned species of Therevidae, and most descriptions lack de- a unique identiÞer, that number was used in prefer- tail. For this study, only the pupal stage was examined. ence to the MEI#. This unique identiÞer, together The terminology for Asiloidea pupal morphological with all label information, was incorporated into characters is not well established. Such information in Mandala, a database designed to log data about and the literature is scattered and inconsistent. Therevid track individual therevid specimens (Kampmeier and pupal morphology is conÞned to the works of DeMei- Holston 2002). These data are available and searchable jere (1916), English (1950), Hennig (1952), Brauns through the Internet (http://pherocera.inhs.uiuc. (1954), and Irwin (1972, 1973). Additional informa- edu/index.htm). tion comes from publications about Asilidae pupae 0013-8746/03/0738Ð0765$04.00/0 ᭧ 2003 Entomological Society of America November 2003 HAUSER AND IRWIN:NEARCTIC GENUS Ammonaios 739 (Melin 1923, Musso 1978) and Bombyliidae pupae evinae (Metz 2002) suggest a putative sister group (Hull 1973), both of which are closely related to the relationship between species of Ammonaios Irwin and Therevidae. Inconsistencies in terminology include Lyneborg and Arenigena Irwin and Lyneborg. These the number of abdominal segments and abdominal two genera were also found to be closely associated spiracles, which vary among authors and are not in- with species in the genera Brachylinga Irwin and cluded in most. In this study, an overview of the Lyneborg, Chromolepida Cole, Lysilinga Irwin and morphology of therevid pupae is provided with the Lyneborg, and Rhagioforma Irwin and Lyneborg. aim of clarifying the use of terminology. The four genera were included in the morphological Description of Species. Adult terminology follows dataset, and Penniverpa Irwin and Lyneborg was Irwin and Lyneborg (1981a, b), McAlpine et al. used as an outgroup in the study presented in this (1981), and Winterton et al. (1999). We use the term work. To test the hypothesis of the monophyly of “pubescent” instead of “pruinescence” for the silver Ammonaios with respect to Arenigena, Brachylinga, microtrichia on head and thorax. The term pruines- Chromolepida, Lysilinga, and Rhagioforma, the follow- Downloaded from https://academic.oup.com/aesa/article/96/6/738/14279 by guest on 22 September 2020 cence is often used for “waxy bloom covering insects ing taxa were chosen to represent the above listed like Odonata” (Nichols 1989), while “pubescent” is genera: Arenigena marcida (Coquillett), Arenigena deÞned as “clothed with soft, short, Þne, loosely set semitaria (Coquillett), Brachylinga cinerea (Cole), hairs.” This description reßects better the microtrichia Brachylinga baccata (Coquillett), Chromolepida bella covering the head and thorax. Descriptions and rede- (Cole), Lysilinga aurantiaca (Coquillett), Rhagio- scriptions of the species are based on holotype spec- forma maculipennis (Kro¨ber), and Penniverpa festina imens. Variation found in other specimens is recorded (Coquillett). within that description in parentheses. The following Phylogenetic analyses followed the cladistic philos- abbreviations are used: av, anteroventral macrosetae ophy of parsimony promoted by Hennig (1966). of the femora; dc, dorsocentral macrosetae of mesono- The outgroup was used to establish character polari- tum; np, notopleural macrosetae of mesonotum; pa, ties. Data were recorded in WINCLADA version postalar macrosetae of mesonotum; sa, supra-alar 0.9.99m24 (Nixon 1999), and an exhaustive search was macrosetae of mesonotum; sc, scutellar macrosetae. performed using PAUP* 4.0b10 (Swofford 2001). All ALM ϭ A. L. Melander, CRN ϭ C. R. Nelson, DWW ϭ multistate characters were treated as nonadditive. The D. W. Webb, ELS ϭ E. L. Sleeper, EMF ϭ E. M. Fisher, character states are described in Table 1, and the data FDP ϭ F. D. Parker, JAP ϭ J. A. Powell, JLF ϭ J. L. matrix is shown in Table 2. Fisher, MAC ϭ M. A. Cazier, MEI ϭ M. E. Irwin, States of characters that were not known in certain RCM ϭ R. C. Miller, DYA ϭ D. Yanega. species were scored as “?”. Bremer support values Illustrations. Genitalia were macerated in 10% KOH were calculated using SEPAL version 1.4 (Salisbury overnight to remove soft tissue, rinsed in distilled 2000) and added to the cladogram (Fig. 2). water, and dissected under a Wild/Leica MZ8 binoc- ular dissecting microscope. Female reproductive or- gans were stained with a saturated solution of Chlo- Results and Discussion rozol Black in 75% ethanol. Preparations were retained in glycerin in genitalia vials mounted beneath Cladistic Analysis. Parsimony analysis to test the the specimens. Images of preparations were captured monophyly of Ammonaios with respect to its putative electronically with a digital camera and enhanced related genera resulted in three most parsimonious using Adobe Photoshop 5.0. Line drawings were made trees of 71 steps. The strict consensus tree of 74 steps by the Þrst author using Adobe Illustrator 8.0 aided by had a consistency index (CI) of 0.52 and a retention the digital images. index (RI) of 0.68 (Fig. 2). Cladistic Analysis. The internal hierarchy of the The Arenigena ϩ Ammonaios clade is supported by Therevidae remains unclear. Lyneborg (1976) and several synapomorphies, including the pale yellow Irwin and Lyneborg (1981a) divided the family into macrosetae of the thorax and the missing hindcoxal two subfamilies, the Phycinae and Therevinae. While knob. The coloration of the thoracic macrosetae is the Phycinae were split into two tribes, the Phycini found in several other therevid genera (e.g., Ammoth- and the Xestomyzini (Lyneborg 1976), the highly di- ereva Lyneborg) and therefore homoplasic. The ab- verse Therevinae were left with no formal tribal clas- sence of the hind coxal knob(character 16) is a strong siÞcation. Gaimari and Irwin (2000) erected the tribe diagnostic feature of this clade, and this state is only Cyclotelini for a Laurasian group of Therevinae. These found in two other genera: the Phycini genus Actorthia studies helped to characterize one monophyletic Kro¨ber (which belongs in a separate subfamily and is group of Therevinae, but left the majority of genera without a doubt not closely related) and Ammothereva lacking placement in named groups. Winterton et al. (lepida Lyneborg & mesasiatica Zaitzev), a Palaearctic (2001) described a third subfamily, Agapophytinae, genus placed in the Cyclotelini (Gaimari and Irwin for a group of Australasian genera.