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Diomus lupusapudoves, sp. nov. (Figs. 1–7, 9, 11–15) Diagnosis. Due to variability in the dorsal color pattern (Figs. 4–7), the new species is best identified by the exact configuration of the adult male genital structures (Figs. 11–12) and by the myrmecophilous, onisciform (=platyform) larva (Figs. 14–15) possessing a finely granulate dorsum devoid of setae, and with the epipleurum of each abdominal segment extended into an oblique lateral plate, forming a protective skirt-like border to shield the underside of the body and appendages. This species closely resembles another myrmecophile, Diomus thoracicus (Fabricius, 1801), recorded from northern South America and the Antilles, to Mexico and southern Florida (Peck 2015), but the adult of our new species is smaller on average (1.7–2.1 mm vs. 2.0– 2.4 mm). Diomus thoracicus male genitalia (illustrated in Gordon 1999) are structurally quite similar as well, but possess at least 1.5× the number of setae along the outer margins of each paramere and have the trabes strongly inflated in apical 2/3. The larva of D. thoracicus is also onisciform (Vantaux et al. 2010; Roux et al. 2017), but has the dorsal surface a uniform light bluish gray except for the contrasting white epipleurum of each abdominal segment. The perimeter of the body is distinctly fimbriate in D. thoracicus, whereas the new species has only a few setae on the head and posterior end of the abdomen. In addition, the head of the D. thoracicus larva projects anteriorly, and is not enclosed laterally by the sides of the pronotum as it is in the new species. Although larvae of both species are myrmecophilous, D. thoracicus larvae are intranidal parasites that feed on ant brood, whereas larvae of the new species are coccidophagous and occur on open vegetation. Another species, D. urban Gordon, 1999 (Fig. 8), was found infrequently alongside the new species among colonies of C. viridis in the coffee agroecosystem that we studied in Chiapas, Mexico. Males and females of D. urban are superficially very similar to the unspotted male form of the new species (Figs. 5–6), but actually belong to an entirely different group within Diomus (Diomus Group G, sensu Gordon 1999) characterized by the male genitalia with extremely wide and densely setose, funnel-shaped parameres, and the penis with an apical flagellum. Females belonging to this group are distinguished by a heavily sclerotized, cylindrical or spindle-shaped nodulus and elongate tapered cornu of the spermathecal capsule. Externally, adults of D. urban can be separated from the new species by their slightly more robust form and the longer intercoxal process of the prosternum (Fig. 10) with the carinae more narrowly separated posteriorly and more weakly convergent anteriorly. Description of holotype (adult, male) (Fig. 4). Length 2.0 mm, width 1.5 mm. Form broadly oval, convex (height = 0.9 mm). Metathoracic wing present. Dorsal surfaces finely granulate, feebly shining, distinctly punctate, pubescent. Coloration of head including mouthparts pale yellow with mandibular apex reddish amber; pronotum pale yellow with large irregularly rounded basomedian reddish brown spot. Elytron predominantly black with faint bluish sheen, with diffusely lighter yellow brown elytral apex; disc bearing large teardrop shaped oblique reddish orange mark; elytral epipleuron yellow brown with margins narrowly dark brown. Scutellar shield dark brown. Venter predominantly brown, darkest on meso-, metaventrite; prosternum pale yellow with median half yellow brown; mesepimeron paler than surrounding sclerites with margins narrowly darkened; abdomen pale brown, lighter, yellower toward apex. Legs pale yellow with meso-, metacoxae slightly darker. Pubescence shiny off white. Dorsal punctation moderately coarse; punctures separated by approximately 1× diameter on elytron, equal in width to eye facet; punctures slightly coarser, more crowded on head, pronotum. Dorsal pubescence semierect, moderately dense, evenly distributed, lacking distinct setal pattern; individual setae equal to about 1/3 to 3/4× length of scutellar shield, arcuate; elytral setae directed more or less posteriorly except directed outwardly at sides of body, posteromedially near suture. Head large, 0.64× width of pronotum; eye large, finely facetted, with interfacetal setae, distinctly notched near antennal insertion by small triangular ocular canthus; inner orbits evenly arcuate, with minimum separation near midlength; interocular distance 1.6× width of eye in frontal view. Antenna composed of 11 antennomeres; antennomere 3 elongate, about 2.3× length of antennomere 4; last four antennomeres subequal in length, forming gradual oval club expanding apically from antennomere 8–10; antennomere 11 subrhomboidal, slightly narrower, than 10. Maxillary palp with terminal palpomere strongly expanded distally, triangulate, about as long as greatest width. Pronotum with basal width about 2× length, tapered toward apex, strongly convex. Elytron in dorsal view with lateral margin evenly arcuate; elytral apices dehiscent. Ventral surfaces pubescent, distinctly punctate; punctation less even, generally less dense than elytral punctation. Prosternum (Fig. 9) with intercoxal process short, broad, with convergent carinae extending to, merging near apex, framing ovotriangular depression. Suture between abdominal ventrites 1 and 2 distinct, linear; 5th ventrite with apex shallowly, roundly emarginate; 6th ventrite with apex bearing indistinct shallow notch at middle. Tarsal claw with broad scythe-like inner tooth extending from base to apical 1/3 or beyond. Male genitalia (Figs 11–12). Basal lobe (=penis guide sensu Ślipiński 2007) moderately flat, in ventral view expanding from base to apical 2/5, tapered beyond to pointed apex, asymmetrical, about 2/3 length of paramere. Paramere with apical 1/2 roundly expanded, with about 19–25 long setae along perimeter, with few shorter setae in more proximal position on each side; setae slightly flattened, broad at base, sharply pointed distally; inner (=ventral) surface of paramere with very short setae sparsely distributed. Penis (=aedeagus or sipho) with outer arm of capsule short, truncate, bearing semicircular crest on outer surface; inner arm short, roundly tapered; penis apex lacking flagellum, with slightly expanded membranous area. Female (Fig. 7). Similar to male except body form proportionally shorter, dorsal coloration uniformly medium brown. Prosternum and underside of head yellow brown. 5th abdominal ventrite with posterior margin roughly linear in median 1/3; 6th ventrite with posterior margin arcuate. Tarsal claw with short triangular tooth near base, not extending beyond apical 1/2. Spermathecal capsule of female genitalia (Fig. 13) moderately small, weakly bent near middle; nodulus (=collum) in the form of short annular projection; ramus sessile, with thorn-like apodeme (=beak sensu Gordon 1999) above accessory gland; cornu short, distinctly swollen distally. Sperm duct lacking sclerotized sheath or process (=infundibulum auctorum). Bursa with lightly sclerotized internal chamber (=bursal plate sensu Gordon 1999) visible as light brown ring-like structure. Variation (Figs 4–7). Length 1.7–2.1 mm. Male with basal mark on pronotum variable in size; reddish orange oblique mark on elytron may be absent or only faintly indicted as slightly lighter area on disc; pale band at elytral apex yellow to brown or indistinct. Female with dorsal coloration light brown to blackish, unicolorous or with anterior pronotal angles and extreme elytral apex defusely lighter. Larva (based on field collected 2 nd –4 th instars) (Fig. 2, 14-15). Form broadly oval, onisciform. Body light grayish tan with head, thoracic and terminal abdominal plates medium brown. Anterior margin of head, posterior margin of abdominal apex with few simple setae. Dorsum devoid of setae, with granulate texture consisting of tiny fingerprint-like ridges and pits (visible at 50× magnification or greater), with eight conspicuous pairs of intersegmental pores near anterior borders of abdominal segments 1–8; first pair situated more anteriorly, appearing to extend onto base of metanotum. Head with frontal arms of epicranial suture well developed; epicranial stem obsolete. Pronotum with pair of pigmented plates; external pronotal margins expanded, flattened, surrounding sides of head. Meso-, metanotum similarly expanded, each with two pairs of small pigmented plates. Abdominal segments transverse, with expanded, flattened epipleurum; tergum 9 with v-shaped pigmented plate. Venter concave, without strongly sclerotized plates; legs short, robust, not capable of extending beyond sides of body; pygopod well developed. Pupa (Fig. 3). Form broadly oval, attached at caudal end, not enclosed in shed larval skin; surface bearing glandular hairs. Coloration yellow to yellowish brown. Trophic relations. Larvae and adults have been observed feeding on Coccus viridis (Green) on coffee plants, especially those tended by Azteca sericeasur Longino and Pheidole synanthropica Longino ants. Etymology. The species name is a concatenation of the Latin phrase “lupus apud oves” (=wolf among the sheep), in reference to its presence among coccids tended by ants. Type material. Holotype (male) with labels: “MEX: Chiapas: Finca Irlanda, 15.173583°−92.336081°, 28.July.2010, coll. H. Liere / On Coffea arabica plants among C. viridis, newly eclosed adult / HOLOTYPE, Diomus lupusapudoves Vandenberg, Iverson & Liere, 2018 ” (USNM); 19 paratypes (9 females, 10 males): 2 with same labels as type except third label “PARATYPE, Diomus lupusapudoves Vandenberg, Iverson & Liere, 2018 ” (USNM); 3 with labels “MEX: Chiapas: Finca Irlanda, 15.173583° −92.336081°, 24.May.2010, coll. A. Iverson / On Coffea arabica plants / PARATYPE, Diomus lupusapudoves Vandenberg, Iverson & Liere, 2018 ” (USNM); 14 with labels “MEX: Chiapas: Finca Irlanda, 15.173583° −92.336081°, 10.June.2010, coll. A. Iverson / Reared from late instar onisciform larva collected on Coffea arabica plants / PARATYPE, Diomus lupusapudoves Vandenberg, Iverson & Liere, 2018 ” (13 USNM, 6 ECO-TAP-E) Other material examined. A small amount of additional material of the new species bearing the same collection data as the 24.May.2010 and 10.June.2010 paratypes has been deposited in the USNM. These represent less well preserved exemplars (either disarticulated, fragmented, or rubbed), but still deemed useful for studying certain morphological or anatomical details. Specimens from each collection event have been placed together on a single pin using multiple points and/or within a gelatin capsule. A vial of mixed second through fourth instar larvae of the new species from the 10.June.2010 collection event has been deposited in the USNM alcohol collection. A male and a female specimen of D. urban from the 24.May.2010 collection event have been point-mounted and deposited in the USNM dry collection. The later collection also contains a large quantity of material of other South American Diomini documented in the Gordon (1999) monograph of this group and utilized for comparative purposes during our study. Remarks. Gordon (1999) informally divided the genus Diomus into eight species groups (Diomus groups A through H) based almost entirely on male genitalic characteristics. He indicated that some of these groups may be paraphyletic, but still have a value for identification purposes. Using his system, our new species belongs in group B and appears to be closely allied to D. thoracicus, the type species of the genus. Our new species exhibits strong sexual dimorphism with respect to the dorsal color pattern (Figs. 4–7). This situation is not uncommon in the tribe Diomini, and probably explains why the females of many other species have not been associated with their male counterparts. We have managed to include females in our type series because both sexes were reared together from the same distinctive onisciform larvae, and have the same configuration of the antenna, prosternal process, punctation, and pubescence (dorsal setal pattern).

Vandenberg, Natalia J., Iverson, Aaron, Liere, Heidi (2018): A new species of myrmecophilous lady beetle in the genus Diomus (Coleoptera: Coccinellidae: Diomini) from Chiapas, Mexico that feeds on green coffee scale, Coccus viridis (Green) (Hemiptera: Coccidae). Zootaxa 4420 (1): 113-122, DOI: https://doi.org/10.11646/zootaxa.4420.1.6

Diomus Mulsant Scymnus (Diomus) Mulsant 1850: 951. Type species: Coccinella thoracica Fabricius, 1801, by subsequent designation of Korschefsky 1931. Diomus: Weise 1895:144. Nephus (Diomus): Iablokoff-Khnzorian 1976: 377. Amidellus Weise 1923: 141. Type species: Scymnus ementitor Blackburn, 1895 by original designation. Synonymized by Ślipiński 2007: 87 (see Gordon (1976) and Pang & Gordon (1986) for a more complete bibliography). Diomus is the most speciose genus in the tribe Diomini Gordon, 1999, and possibly the largest genus in the entire family Coccinellidae Latreille, 1807 (Pang & Ślipiński 2009, 2010). Diomus was originally placed as a subgenus of Scymnus Kugellan, 1794, and classified, until recent times, in the tribe Scymnini Mulsant, 1846 along with a miscellaneous assortment of other small pubescent lady beetles. Gordon (1999) recognized Diomus and allies as deserving of their own tribe Diomini, distinct from Scymnini, but unfortunately his circumscription of the former included some genera belonging to another tribe���Selvadiini Gordon, 1985 (Vandenberg 2002; Vandenberg & Hanson in review). A re-circumscription and review of Diomini is detailed in Vandenberg and Hanson (in review) and will not be repeated here., Published as part of Vandenberg, Natalia J., Iverson, Aaron & Liere, Heidi, 2018, A new species of myrmecophilous lady beetle in the genus Diomus (Coleoptera: Coccinellidae: Diomini) from Chiapas, Mexico that feeds on green coffee scale, Coccus viridis (Green) (Hemiptera: Coccidae), pp. 113-122 in Zootaxa 4420 (1) on page 114, DOI: 10.11646/zootaxa.4420.1.6, http://zenodo.org/record/1247206, {"references":["Slipinski, A. (2007) Australian Ladybird Beetles (Coleoptera: Coccinellidae): Their Biology and Classification. Australian Biological Resources Study, Canberra, ACT, 288 pp.","Gordon, R. D. (1976) The Scymnini of the United States and Canada: Key to genera and revision of Scymnus, Nephus and Diomus. Bulletin of the Buffalo Society of Natural Sciences, 28, 1 - 362.","Pang, X. F. & Gordon, R. D. (1986) The Scymnini (Coleoptera: Coccinellidae) of China. The Coleopterists Bulletin, 40, 157 - 199.","Gordon, R. (1999) South American Coccinellidae (Coleoptera), Part VI: A systematic revision of the South American Diomini, new tribe (Scymninae). Annales Zoologici, Warsaw, 49, 1 - 219.","Pang, H. & Slipinski, A. (2009) Revision of the Australian Coccinellidae (Coleoptera). Genus Diomus Mulsant. Part 1. Annales Zoologici, 59, 641 - 698. https: // doi. org / 10.3161 / 000345409 x 485008","Pang, H. & Slipinski, A. (2010) Revision of the Australian Coccinellidae (Coleoptera). Genus Diomus Mulsant. Part 2. Annales Zoologici, 60, 493 - 545. https: // doi. org / 10.3161 / 000345410 X 550382","Vandenberg, N. J. (2002) Coccinellidae Latreille, 1807. In: Arnett, R. & Thomas, M. (Eds.), American Beetles. Vol. 2. Polyphaga: Scarabaeoidea through Curculionoidea. CRC Press, Boca Raton, FL, pp. 371 - 389."]}

The idea that noncrop habitat enhances pest control and represents a win–win opportunity to conserve biodiversity and bolster yields has emerged as an agroecological paradigm. However, while noncrop habitat in landscapes surrounding farms sometimes benefits pest predators, natural enemy responses remain heterogeneous across studies and effects on pests are inconclusive. The observed heterogeneity in species responses to noncrop habitat may be biological in origin or could result from variation in how habitat and biocontrol are measured. Here, we use a pest-control database encompassing 132 studies and 6,759 sites worldwide to model natural enemy and pest abundances, predation rates, and crop damage as a function of landscape composition. Our results showed that although landscape composition explained significant variation within studies, pest and enemy abundances, predation rates, crop damage, and yields each exhibited different responses across studies, sometimes increasing and sometimes decreasing in landscapes with more noncrop habitat but overall showing no consistent trend. Thus, models that used landscape-composition variables to predict pest-control dynamics demonstrated little potential to explain variation across studies, though prediction did improve when comparing studies with similar crop and landscape features. Overall, our work shows that surrounding noncrop habitat does not consistently improve pest management, meaning habitat conservation may bolster production in some systems and depress yields in others. Future efforts to develop tools that inform farmers when habitat conservation truly represents a win–win would benefit from increased understanding of how landscape effects are modulated by local farm management and the biology of pests and their enemies.

Se presentan los resultados de una serie de estudios para documentar y evaluar el conocimiento tradicional de manejo de plagas en granos de maíz almacenado entre agricultores mayas. Se realizaron 157 entrevistas en cinco comunidades de Los Altos de Chiapas y tres comunidades del altiplano guatemalteco. Sithophilus zeamais y Sitotroga cerealella fueron los insectos más comúnmente reportados. El 50% de los agricultores usa insecticidas, muchas veces en una forma inapropiada. Sin embargo aun utilizan varias prácticas tradicionales de manejo, que son en su mayoría de carácter preventivo (variedades criollas, fechas estrictas de cosecha, secado del maíz antes de guardarlo, aplicación de cal, e incorporación de plantas repelentes y utilización de graneros fríos y secos). Se establecieron experimentos para probar la efectividad de estas prácticas. El uso de variedades criollas amarillas, la incorporación de hojas de Piper auritum, y un lugar seco y frío para el almacenamiento parecen ser prácticas efectivas para reducir el ataque de plaga. A través de talleres se divulgaron los resultados de la investigación, con el fin de invitar a los jóvenes agricultores de la región a probar las prácticas que inventaron sus ancestros. Una encuesta realizada un año después de los talleres sugiere que los talleres provocaron cambios positivos entre los jóvenes y su actitud hacia las prácticas tradicionales. Los principios del conocimiento tradicional maya para la protección del maíz almacenado tienen potencial para la agricultura orgánica y la seguridad alimentaria en uno de los centros de domesticación del maíz, dos prioridades de la agricultura de hoy y el mañana. Abstract: We present results of a series of studies documenting and evaluating traditional knowledge of pest in stored grains among Mayan farmers. We performed 257 interviews in five communities in the Chiapas highlands and in three communities in the Guatemalan highlands. Sithophilus zeamais and Sitotroga cerealella were the most commonly reported insects. Fifty % of farmers use the pesticide aluminum phosphide or malathion, often in inappropriate ways. However they still employ several traditional management practices, the majority of which are preventative (local varieties, strict harvest dates, drying maize before storage, lime application, incorporation of repellent plants and cool, dry granaries). We conducted experiments to test the efficacy of these practices. The use of traditional yellow corn variety, the incorporation of Piper auritum leaves and lime in the storage, and dry, cool storage room seem to reduce pest attacks. We communicated our findings through workshops inviting young farmers to try the techniques invented by their ancestors. A survey performed a year after the workshops suggested that the workshops induced positive changes in young farmers’ attitudes towards traditional practices. The principles of Maya traditional knowledge of stored grain protection have potential for application to organic agriculture and for food security in one of the domestication centers of maize, two priorities for today’s and tomorrow’s agriculture.