Introduction

Brush-footed butterflies (Nymphalidae) represent the second most diverse family of Papilionoidea worldwide, behind the skippers (Hesperiidae). Because of the remarkable diversity and local endemism featured within Nymphalidae, the description and analysis of spatio-temporal patterns of this group are a priority for advancing conservation and systematics. This is particularly true for Mexico, which is a megadiverse country and biodiversity hotspot where Nymphalidae constitute 25 % (413 species) of the country's Papilionoidea fauna sensu lato (^{Llorente-Bousquets et al., 2014}).

Oaxaca is one of the most biodiverse states in Mexico (^{Flores-Villela & García-Vázquez, 2014}; ^{García-Mendoza & Meave del Castillo, 2011}; ^{Navarro-Sigüenza et al., 2014}), and this pattern is reflected in Nymphalidae. Some 339 species or 82 % of the country's nymphalids are documented from Oaxaca, ranking it second only to the state of Chiapas in nymphalid species richness (^{Luis-Martínez et al., 2016}). This outstanding biodiversity in Oaxaca is attributable to the convergence of five different biogeographic provinces in the state, with the most well-represented of these being the Sierra Madre del Sur, Costa del Pacífico, and Golfo de México (^{Morrone, 2005}; ^{Morrone et al., 2002}). The Loxicha Region of Oaxaca lies within the Sierra Madre del Sur, and it is of special faunal interest. Loxicha experienced two main collecting periods in the 20^th century, during which numerous species of Nymphalidae were described and named (^{Luis-Martínez et al., 2020}). The MARIPOSA database (^{Luis-Martínez et al., 2005}), contains 1 248 records from the Loxicha Region during that century, with 139 species of Nymphalidae being documented by more than 30 collectors. Particularly notable among those collectors were Eduardo Cecilio Welling with 66 species (265 records), and John Kemner with 78 species (402 records).

Modern description and analysis of the Papilionoidea from the Pacific slope of the Loxicha Region has been the core focus of an ongoing project, begun in 2005, to analyze the butterfly fauna of Oaxaca (^{Luis-Martínez et al., 2016}). To date, the families Papilionidae, Pieridae, and Riodinidae of the Loxicha Region have been analyzed (^{Arellano-Covarrubias et al., 2018}; ^{Luis-Martínez et al., 2020}). The present study aims to describe the temporal and spatial patterns of Nymphalidae diversity in the Loxicha Region. Based on a review of the literature and historical records, coupled with sampling from 2005-2014 along an elevational gradient from 80-2 600 m, we document this diversity and make a preliminary comparison of nymphalids in Loxicha to other comparatively well-sampled regions to describe broad-scale patterns.

Historical outline of the collection of Papilionoidea from the Pacific slope and the Loxicha Region: The historical collection and classification of Mexican species of Papilionoidea began at the end of the 19^th century and continued through the early 1980's. Collectors generally focused on the Southeastern states, the Atlantic slope, and the states of Guerrero and Morelos due to the high diversity of these areas and to the presence of associated highways (v. gr.^{Llorente-Bousquets et al., 1986}; ^{Llorente-Bousquets & Luis-Martínez, 1993}; ^{Llorente-Bousquets et al.,1998}; ^{Luis-Martínez et al., 2000}; ^{Luis-Martínez et al., 2003}; ^{Michán et al., 2004}). During this period, sporadic collections were also made in Northern Mexico, mostly carried out by academic institutions of the USA (v. gr.^{Comstock, 1953}; ^{Holland, 1995}; ^{Spade et al., 1988}; ^{Stanford, 1998}). The Pacific slope of Mexico was often ignored by collectors, resulting in relatively few publications except for a butterfly checklist for the Chamela Biological Research Station in the state of Jalisco (^{Beutelspacher, 1982}), notes on the butterflies of some Pacific islands (^{Vázquez, 1958}; ^{Vázquez, 1959}; ^{Vázquez, 1960}), and a contribution on the fauna of the Pacific slope of Jalisco (v. gr.^{Comstock & Vázquez, 1961}). Additionally, Members of the Mexican Society of Lepidopterology published the results of periodic collections along this slope (v. gr.^{Maza & Maza, 1981}; ^{Maza & Maza, 1983}; ^{Maza et al., 1982}; ^{Velázquez, 1976}; ^{Velázquez & Velázquez, 1975}), with the main goal of describing new taxa from unexplored areas.

The first systematic sampling of the Pacific slope extended from the coast (Puerto San Blas) to the mountains (Sierra San Juan) in the state of Nayarit during 1978-1980, spanning an elevational gradient from sea level to 1 300 m. This effort documented 135 species of Nymphalidae, marking the beginning of dedicated research on the distribution of Papilionoidea from the Pacific slope. A decade later, faunistic studies were carried out in the Sierra de Atoyac (^{Vargas-Fernández et al., 1994}) and the Omiltemi region (Luis-Martínez & ^{Llorente-Bousquets, 1993}) of the Sierra Madre del Sur (SMS) in the state of Guerrero. The former spanned an elevational range of 300-3 100 m, and the latter a range of 2 300-3 000 m (v. gr.^{Llorente-Bousquets, 1984}; ^{Llorente-Bousquets et al., 2004}; ^{Warren & Llorente-Bousquets, 1999}).

Further studies on the faunistic composition of Papilionoidea from the Pacific slope were completed during the last three decades in Pedernales, state of Michoacán (^{Balcázar, 1993}); Mismaloya, Jalisco and Bahía de Banderas, Nayarit (^{Warren & Llorente-Bousquets, 1999}); the Sierra de Manantlán, Jalisco-Colima (^{Vargas-Fernández et al., 1999}); and Western Michoacán (^{Luis-Martínez, 1997}; ^{Luis-Martínez, 1999}). Additional analyses of the alpha and beta diversity of the Nymphalidae (^{Tapia-Sedeño, 2013}) and the lepidopterofauna of the Loxicha Region, Oaxaca (^{Arellano-Covarrubias et al., 2018}; ^{Luis-Martínez et al., 2020}) were also released. Most of these studies focused on the local, regional, or elevational distribution and the phenology of Papilionoidea species, under distinct ecological conditions and across a wide environmental gradient. Some faunal comparisons between different areas have also been made (v. gr.^{Monteagudo-Sabaté & Luis-Martínez, 2013}; ^{Monteagudo-Sabaté et al., 2001}; ^{Monteagudo-Sabaté et al., 2014}).

When analyzing the fauna of the Pacific region and the Sierra Madre del Sur, the diversity of the state of Morelos must be considered. This state is located mainly in the Eje Neovolcánico and Cuenca del Balsas biogeographic provinces (^{Morrone et al., 2002}). Michoacán and Guerrero also include portions of these two provinces. More than half of Guerrero lies in the Cuenca del Balsas, and the state also encompasses a large portion of the Sierra Madre del Sur, particularly its Pacific slopes (^{Luna-Reyes et al., 2012}). There are 450 species or subspecies of Papilionoidea sensu lato recorded from Morelos, classified in 214 genera. The Nymphalidae is represented in Morelos by 147 species or subspecies, of which 42 are endemic to Mexico (^{Luna-Reyes, 2020}).

Besides these faunistic studies over the past three decades, species lists have been published for 10 of the 11 states in the Pacific slope. Table 1 presents current data for the number of species and endemics in these Mexican states according to ^{Llorente-Bousquets et al. (2014}) and ^{Luis-Martínez et al. (2016}).

Materials and methods

Faunistic inventory and sites: To update the Papilionoidea species list for Oaxaca published by ^{Luis-Martínez et al. (2004}), systematic sampling was begun in 2005 (^{Luis-Martínez et al., 2016}) which increased scientific knowledge of the geographical and vegetational distribution of the group. This sampling effort focused on areas with the greatest diversity and endemism. The Loxicha Region is one such area, and thus was subject to 267 sampling days over seven years (2005, 2007, 2008, 2011-2014), including 21 sampling sites that span eight municipalities within the Pacific slopes of the Sierra Madre del Sur (Table 2). In 12 of these sites, sampling was systematic. A total of 16 collectors participated in the sampling effort, with 13 to 65 sampling days per site. Sites were grouped by elevational levels and vegetation type for comparison and analysis purposes. Vegetation classification followed ^{Rzedowski (1978}) and ^{Llorente-Bousquets (1984}), with four types recognized in the Loxicha Region: tropical deciduous forest (TDF), tropical sub-deciduous forest (TSDF), cloud forest (low- and mid-elevation) (CF), and oak-pine forest (OPF). Besides these, a fifth vegetation type was recognized in some sites at 2 000-2 400 m elevation, denominated as oak-pine and high-elevation cloud forest (OPCF). OPCF is similar to OPF but has intermixed elements of CF. Because the OPCF can be easily distinguished from both the OPF and the CF, and is located at different elevations in the region, this vegetation type was considered a distinct category (^{Arellano-Covarrubias et al., 2018}; ^{Luis-Martínez et al., 2020}).

Taxonomic determination: Taxa were identified by comparison with specimens in the Lepidoptera Collection of the Zoology Museum, Facultad de Ciencias, Universidad Nacional Autónoma de México (MZFC), together with the taxonomic expertise of the authors and reference to specialized literature. The list of species follows the taxonomic order proposed by ^{Vargas-Fernández et al. (2016}), and ^{Llorente-Bousquets, Luis-Martínez et al. (2006}), for the Satyrinae subfamily. All specimens were deposited in the Lepidoptera Collection of the MZFC, which is registered at the Secretaría de Medio Ambiente, Recursos Naturales y Pesca (SEMARNAP) (DFE.IN.071.0798). Specimens were collected under scientific collecting permit FAUT-0148 issued by the Secretaría de Medio Ambiente y Recursos Naturales (SEMARNAT). Collecting data were entered into the MARIPOSA database (^{Luis-Martínez et al., 2005}).

Nets and Van Someren-Rydon traps: Sampling techniques included 4-6 aerial nets set for eight hours and 10-20 Van Someren-Rydon traps (Rydon, 1964) placed daily 1-2.5 m high along transects, with 50 m between each trap. Traps used a mixture of water, brown sugar, pineapple, and banana as bait. Transects covered distinct microhabitats (open and closed vegetation) to obtain a more representative sample. The number of specimens captured with traps in each locality is presented in Table 2.

Species richness estimation and diversity analysis by vegetation type and elevational level: A species accumulation curve was estimated using data from all specimens collected. Data were randomized (500 runs) with EstimateS 9.1 (^{Colwell, 2013}) and fitted to the Clench model (^{Soberón & Llorente-Bousquets, 1993}) to estimate species richness. Species richness was also estimated for each vegetation type (Table 2) and three elevational levels: 0-750 m, 750-1 800 m, and 1 800-2 850 m (^{Luis-Martínez et al., 2020}). For the elevational analysis, the non-parametric estimation method Chao1 (^{Colwell & Coddington, 1994}) was implemented in SPADE (^{Chao & Shen, 2010}). For each estimation, the 95 % confidence interval (CI) was estimated using the bootstrap technique. Significant differences between the species richness of distinct vegetation types or elevational levels were evaluated by comparison and overlap of the confidence intervals.

Additionally, the real diversity defined as the exponential of the Shannon-Wiener index (H') was estimated for each elevational level along with the 95 % CI, using the method proposed by ^{Chao and Shen (2003}) implemented in SPADE (^{Chao & Shen, 2010}). The scale of the real diversity (effective number of species) is linear; therefore, the values of each elevational level can be compared directly using the CI overlap (^{Jost, 2006}).

Species composition similarity analysis: Similarities were estimated in species composition between the Loxicha Region and other regions with roughly equivalent sampling effort on the Pacific and Atlantic slopes of Oaxaca and other states. Besides Loxicha, our analysis included the Sierra de Juárez, Oaxaca (^{Luis-Martínez et al., 1991}), the Sierra Mazateca, Oaxaca (^{Álvarez-García et al., 2016}), the Sierra de Atoyac de Álvarez, Guerrero (^{Vargas-Fernández et al., 1994}), the Sierra de Manantlán, Jalisco-Colima (^{Vargas-Fernández et al., 1999}) and the Sierra de San Juan, Nayarit (MARIPOSA database). A distance matrix was estimated with presence/absence data of the species in each region using the Jaccard index with the “vegan'' package (^{Oksanen et al., 2019}) in R 4.0.0 (^{R Core Team, 2020}). Using the same method, the similarity among 77 sites distributed across Mexico was estimated, including multiple biogeographic provinces and both Pacific and Atlantic slopes.

Natural history: Some biological observations made during fieldwork are presented, which include elevational migrations and species aggregations among other data. These observations are valuable for describing the fine-scale spatial and temporal distribution of some rare or hard-to-find species and could aid future efforts to collect these species.

Results

Species list: Based on a review of published records (1950-2004) and a query of the MARIPOSA database up to the year 2000, 139 taxa of Nymphalidae were historically recorded from the Loxicha Region. Our subsequent field sampling from 2005-2014 across 21 sites in the region (Table 2) increased that list to 189 taxa, including 10 subfamilies, 23 tribes, 15 subtribes, and 85 genera. Our sampling effort resulted in 28 756 records plus 1 248 records from historical collections archived in the MARIPOSA database, for a total of 30 004 records of Nymphalidae for the Loxicha Region. Data from publications and scientific collections are mostly from the 400-1 400 m elevational range, while records from our field work are distributed from 80-2 850 m. All species and subspecies historically recorded for the region were collected during our fieldwork except for Adelpha donysa ssp., Pedaliodes dejecta ssp., and Actinote guatemalena guerrerensis J. ^{Maza, 1982}.

The Nymphalidae species documented in the Loxicha Region constitute 46 % of Mexican nymphalid species and 56 % of those recorded from Oaxaca (^{Luis-Martínez et al., 2016}). A total of 10 species and 56 subspecies endemic to Mexico are represented in the Loxicha Region. These endemic taxa were binned into four groups according to their degree of endemism (Fig. 1): group 1, endemic to the Loxicha Region (5 spp.); group 2, endemic to the Sierra Madre del Sur (13 spp.); group 3, endemic to the Pacific slope (23 spp.); and group 4, endemic to Mexico (15 spp.). The taxa exclusive to the Loxicha Region are Memphis wellingi (L. Miller & J. Miller, 1976); Cyllopsis jacquelineae (L. Miller, 1974); Callicore texa loxicha (R. G. ^{Maza & J. Maza, 1983}); Chlosyne gaudialis wellingi (L. Miller & Rotger, 1979), and Altinote stratonice oaxaca (J. Miller & L. Miller, 1979).

Species list of Nymphalidae for the Loxicha Region, Oaxaca. Taxa in bold text are endemics, and superscript numbers correspond to their degree of endemism: 1, endemic to the Loxicha Region; 2, endemic to the Sierra Madre del Sur; 3, endemic to the Pacific slope; 4, endemic to Mexico.

Family NYMPHALIDAE

Rafinesque, 1815

Subfamily Libytheinae Boisduval, 1833

1.Libytheana carinenta mexicana Michener, 1943

Subfamily Danainae Boisduval, 1833

Tribe Euploeini Herrich-Schäffer, 1849

Subtribe Itunina Reuter, 1896

2.Anetia thirza thirza Geyer, (1833)

3.Lycorea halia atergatis Doubleday, (1847)

4.Lycorea ilione albescens (Distant, 1876)

Tribe Danaini Boisduval, 1833

Subtribe Danaina Boisduval, 1833

5.Danaus eresimus montezuma Talbot, 1943

6.Danaus gilippus thersippus (Bates, 1863)

7.Danaus plexippus plexippus (Linnaeus, 1758)

Subfamily Ithomiinae Godman & Salvin, 1879

Tribe Tithoreini Fox, 1940

8.Aeria eurimedia pacifica Godman & Salvin, 1879

9.Tithorea harmonia hippothous Godman & Salvin, 1879

10.Tithorea tarricina duenna Bates, 1864

Tribe Melinaeini Clark, 1947

11. Melinaea lilis flavicans Hoffmann, 1924 ³

Tribe Mechanitini Bar, 1878

12.Mechanitis lysimnia utemaia Reakirt, 1866

13.Mechanitis menapis doryssus Bates, 1864

14.Mechanitis polymnia lycidice Bates, 1864

Tribe Oleriini Fox, 1940

15.Oleria paula (Weymer, 1883)

Tribe Dircennini D'Almeida, 1941

16.Dircenna klugii klugii (Geyer, 1837)

17. Episcada salvinia portilla J. Maza & Lamas, 1978 ³

18. Pteronymia artena praedicta J. Maza & Lamas, 1982 ²

19.Pteronymia cotytto cotytto (Guérin-Méneville, (1844))

2. Pteronymia rufocincta (Salvin, 1869) ³

Tribe Godyridini D'Almeida, 1941

21. Greta annette moschion (Godman, 1901) ³

22. Greta morgane morgane (Geyer, 1837) ³

Subfamily Charaxinae Guenée, 1865

Tribe Anaeini Reuter, 1896

23.Hypna clytemnestra mexicana Hall, 1917

24.Consul electra electra (Westwood, 1850)

25.Consul excellens genini (Le Cerf, 1922)

26.Consul fabius cecrops (Doubleday, (1849))

27.Phantos callidryas (R. Felder, 1869)

28.Siderone galanthis ssp.

29.Zaretis ellops (Ménétriés, 1855)

30.Anaea troglodyta aidea (Guérin-Méneville, (1844))

31. Fountainea eurypyle glanzi (Rotger, Escalante & Coronado, 1965) ³

32.Fountainea glycerium glycerium (Doubleday, (1849))

33. Fountainea nobilis rayoensis (J. Maza & Díaz, 1978) ³

34.Memphis forreri (Godman & Salvin, 1884)

35.Memphis perenna perenna (Godman & Salvin, (1884))

36.Memphis pithyusa pithyusa (R. Felder, 1869)

37. Memphis wellingi L. Miller & J. Miller, 1976 ¹

Tribe Preponini Rydon, 1971

38. Archaeoprepona amphimachus baroni J. Maza, 1982 ²

39. Archaeoprepona demophon occidentalis Stoffel & Descimon, 1974 ³

40. Archaeoprepona demophoon mexicana Llorente, Descimon & K. Johnson, 1993 ³

41. Archaeoprepona phaedra ssp. ²

42.Prepona laertes octavia Fruhstorfer, 1905

43. Prepona brooksiana ibarra Beutelspacher, 1982 ³

Subfamily Morphinae Newman, 1834

Tribe Morphini Newman, 1834

Subtribe Morphina Newman, 1834

44.Morpho polyphemus Westwood, (1850)

45. Morpho helenor guerrerensis Le Moult & Réal, 1962 ³

Tribe Brassolini Boisduval, 1836

Subtribe Brassolina Boisduval, 1836

46.Caligo telamonius memnon (C. Felder & R. Felder, 1867)

47.Caligo uranus Herrich-Schäffer, 1850

48.Opsiphanes boisduvallii Doubleday, (1849)

49.Opsiphanes cassina fabricii (Boisduval, 1870)

50.Opsiphanes quiteria quirinus Godman & Salvin, 1881

51.Opsiphanes tamarindi tamarindi C. Felder & R. Felder, 1861

Subfamily Satyrinae Boisduval, 1833

52.Manataria hercyna maculata (Hopffer, 1874)

53. Oxeoschistus hilara ssp. ²

54. Oxeoschistus tauropolis ssp. ³

55. Pedaliodes dejecta ssp. ²

56.Cissia similis (Butler, 1867)

57.Cissia terrestris (Butler, 1867)

58.Cissia sp.

59.Cissia themis (Butler, 1867)

60. Cyllopsis clinas (Godman & Salvin, 1889) ²

61. Cyllopsis diazi L. Miller, 1974 ⁴

62.Cyllopsis hedemanni hedemanni R. Felder, 1869

63. Cyllopsis jacquelineae L. Miller, 1974 ¹

64. Cyllopsis nayarit (R. L. Chermock, 1947) ⁴

65.Cyllopsis pyracmon pyracmon (Butler, 1867)

66.Cyllopsis suivalenoides L. Miller, 1974

67.Euptychia fetna Butler, 1870

68.Hermeuptychia hermes (Fabricius, 1775)

69. Megisto rubricata pseudocleophes L. Miller, 1976 ⁴

70. Paramacera xicaque rubrosuffusa L. Miller, 1972 ²

71.Pindis squamistriga R. Felder, 1869

72.Taygetis kerea Butler, 1869

73. Taygetis mermeria griseomarginata L. Miller, 1978 ³

74. Taygetis uncinata Weymer, 1907 ⁴

75.Taygetis virgilia (Cramer, 1776)

76.Taygetis weymeri Draudt, 1912

77. Gyrocheilus patrobas patrobas (Hewitson, 1862) ⁴

Subfamily Apaturinae Boisduval, 1840

78.Asterocampa idyja argus (Bates, 1864)

79.Doxocopa laure laure (Drury, 1773)

80.Doxocopa pavon theodora (Lucas, 1857)

Subfamily Biblidinae Boisduval, 1833

Tribe Cyrestini Guenée, 1865

81.Marpesia chiron marius (Cramer, 1779)

82.Marpesia petreus ssp. nov.

83.Marpesia zerynthia dentigera (Fruhstorfer, 1907)

Tribe Biblidini Boisduval, 1833

Subtribe Biblidina Boisduval, 1833

84.Biblis hyperia aganisa Boisduval, 1836

85.Mestra dorcas amymone (Ménétriés, 1857)

Subtribe Ageroniina Doubleday, (1847)

86. Hamadryas amphinome mazai Jenkins, 1983 ³

87. Hamadryas atlantis lelaps (Godman & Salvin, 1883) ³

88.Hamadryas februa ferentina (Godart, (1824))

89.Hamadryas glauconome glauconome (Bates, 1864)

90. Hamadryas guatemalena marmarice (Fruhstorfer, 1916) ⁴

Subtribe Epicaliina Guenée, 1865

91.Eunica alcmena alcmena (Doubleday, (1847))

92.Eunica monima (Stoll, 1782)

93.Eunica tatila tatila (Herrich-Schäffer, (1855))

94. Catonephele cortesi R. G. Maza, 1982 ³

95. Catonephele numilia immaculata Jenkins, 1985 ²

96. Myscelia cyananthe cyananthe C. Felder & R. Felder, 1867 ⁴

97. Myscelia cyaniris alvaradia R. G. Maza & Díaz, 1982 ³

98.Myscelia ethusa ethusa (Doyère, (1840))

Subtribe Epiphilina Jenkins, 1987

99. Nica flavilla bachiana (R. G. Maza & J. Maza, 1985) ²

100. Temenis laothoe quilapayunia R. G. Maza & Turrent, 1985 ³

101. Bolboneura sylphis beatrix R. G. Maza, 1985 ³

102. Epiphile adrasta escalantei Descimon & Mast, 1979 ⁴

103. Pyrrhogyra edocla paradisea R. G. Maza & J. Maza, 1985 ³

104.Pyrrhogyra neaerea hypsenor Godman & Salvin, 1884

Subtribe Callicorina Orfila, 1952

105. Diaethria anna mixteca J. Maza, 1977 ²

106. Diaethria astala asteroide R. G. Maza & R. F. Maza, 1985 ²

107. Callicore texa loxicha R. G. Maza & J. Maza, 1983 ¹

108.Cyclogramma pandama (Doubleday, (1848))

Subtribe Eubagina Burmeister, 1878

109.Dynamine dyonis Geyer, 1837

110.Dynamine postverta mexicana D'Almeida, 1952

111.Dynamine theseus (C. Felder & R. Felder, 1861)

Subfamily Limenitidinae Behr, 1864

Tribe Limenitidini Behr, 1864

Subtribe Limenitidina Behr, 1864

112.Adelpha barnesia leucas Fruhstorfer, 1915

113.Adelpha basiloides (Bates, 1865)

114.Adelpha bredowii Geyer, 1837

115. Adelpha diocles ssp. ³

116. Adelpha donysa ssp. ²

117.Adelpha fessonia fessonia (Hewitson, 1847)

118.Adelpha iphicleola iphicleola (Bates, 1864)

119.Adelpha iphiclus iphiclus (Linnaeus, 1758)

120.Adelpha leuceria leuceria (Druce, 1874)

121. Adelpha leucerioides ssp. ³

122.Adelpha lycorias melanthe (Bates, 1864)

123.Adelpha naxia naxia (C. Felder & R. Felder, 1867)

124.Adelpha paraena massilia (C. Felder & R. Felder, 1867)

125.Adelpha phylaca phylaca (Bates, 1866)

126.Adelpha pithys (Bates, 1864)

127.Adelpha serpa celerio (Bates, 1864)

Subfamily Nymphalinae Rafinesque, 1815

Tribe Coeini Scudder, 1893

128.Historis acheronta acheronta (Fabricius, 1775)

129.Historis odius dious Lamas, 1995

130.Pycina zamba zelys Godman & Salvin, 1884

Tribe Nymphalini Rafinesque, 1815

131.Colobura dirce dirce (Linnaeus, 1758)

132.Smyrna blomfildia datis Fruhstorfer, 1908

133.Smyrna karwinskii Geyer, (1833)

134.Hypanartia dione disjuncta Willmott, J. Hall & Lamas, 2001

135.Hypanartia godmanii (Bates, 1864)

136.Hypanartia lethe (Fabricius, 1793)

137.Hypanartia trimaculata autumna Willmott, J. Hall & Lamas, 2001

138.Nymphalis antiopa antiopa (Linnaeus, 1758)

139.Vanessa atalanta rubria (Fruhstorfer, 1909)

140.Vanessa cardui (Linnaeus, 1758)

141.Vanessa virginiensis (Drury, 1773)

Tribe Victorinini Scudder, 1893

142.Siproeta epaphus epaphus (Latreille, (1813))

143.Siproeta stelenes biplagiata (Fruhstorfer, 1907)

144.Anartia fatima fatima (Fabricius, 1793)

145.Anartia jatrophae luteipicta Fruhstorfer, 1907

Tribe Junoniini Reuter, 1896

146.Junonia coenia Hübner, (1822)

147.Junonia evarete nigrosuffusa Barnes & McDunnough, 1916

148.Junonia genoveva ssp. nov.

Tribe Melitaeini Herrich-Schäffer, 1843

Subtribe Nova

149. Chlosyne cynisca (Godman & Salvin, 1882) ⁴

150.Chlosyne erodyle ssp.

151. Chlosyne gaudialis wellingi L. Miller & Rotger, 1979 ¹

152.Chlosyne hippodrome hippodrome (Geyer, 1837)

153.Chlosyne janais janais (Drury, 1782)

154.Chlosyne lacinia lacinia (Geyer, 1837)

155.Chlosyne marina marina (Geyer, 1837)

156.Chlosyne melanarge (Bates, 1864)

157.Chlosyne theona theona (Ménétriés, 1855)

158.Microtia elva elva Bates, 1864

Subtribe Phyciodina Higgins, 1981

159.Phyciodes graphica graphica (R. Felder, 1869)

160.Phyciodes mylitta thebais Godman & Salvin, 1878

161. Phyciodes pallescens (R. Felder, 1869) ⁴

162.Phyciodes phaon phaon (Edwards, 1864)

163.Phyciodes tharos tharos (Drury, 1773)

164.Tegosa guatemalena (Bates, 1864)

165. Anthanassa ardys ardys (Hewitson, 1864) ⁴

166.Anthanassa argentea (Godman & Salvin, 1882)

167.Anthanassa atronia (Bates, 1866)

168.Anthanassa frisia tulcis (Bates, 1864)

169. Anthanassa nebulosa alexon (Godman & Salvin, 1889) ⁴

170. Anthanassa otanes oaxaca Beutelspacher, 1990 ⁴

171. Anthanassa ptolyca amator (Hall, 1929) ⁴

172. Anthanassa sitalces cortes (Hall, 1917) ⁴

173.Anthanassa texana texana (Edwards, 1863)

174.Eresia phillyra phillyra Hewitson, 1852

Subfamilia Heliconiinae Swainson, 1822

Tribe Acraeini Boisduval, 1833

175. Altinote stratonice oaxaca (J. Miller & L. Miller, 1979) ¹

176. Actinote guatemalena guerrerensis J. Maza, 1982 ²

Tribe Heliconiini Swainson, 1822

Subtribe Heliconiina Swainson, 1822

177.Agraulis vanillae incarnata (Riley, 1926)

178.Dione juno huascuma (Reakirt, 1866)

179.Dione moneta poeyii Butler, 1873

180.Dryas iulia moderata (Riley, 1926)

181.Dryadula phaetusa (Linnaeus, 1758)

182.Eueides aliphera gracilis Stichel, 1903

183.Eueides isabella eva (Fabricius, 1793)

184.Heliconius charithonia vazquezae W. P. Comstock & F. M. Brown, 1950

185. Heliconius erato cruentus Lamas, 1998 ³

186.Heliconius hortense Guérin-Méneville, (1844)

187.Heliconius ismenius telchinia Doubleday, 1847

Tribe Argynnini Swainson, 1833

Subtribe Euptoietina Simonsen, 2006

188.Euptoieta claudia daunius (Herbst, 1798)

189.Euptoieta hegesia meridiania Stichel, 1938

Alpha diversity: Considering only the data obtained during our fieldwork, 186 Nymphalidae species were collected. When species from the literature review and historically collected specimens were added, the list reached 189 species. The Clench model estimated 188 species (Fig. 2) while Chao1 estimated 193 species. Therefore, the Clench model underestimated the region's species richness, while the Chao1 estimator was potentially more reliable. According to Chao1, our list is 98 % complete.

Across the 11 states of Mexico's Pacific slope from Baja California to Chiapas (Table 1), the nymphalid species richness of the Loxicha Region alone (189 spp.) surpasses all states except for Guerrero (216 spp.) and Chiapas (351 spp.). The high species richness in Guerrero is attributable to the biogeographic provinces Planicie Costera del Pacífico and Sierra Madre del Sur occupying most of the state, with the SMS having substantial faunal endemism. In Chiapas, the high species richness can be explained by the convergence of Atlantic and Pacific slopes in the state, as well as the presence of tropical evergreen forest, a vegetation type that supports more than 50 % of Mexican species of Papilionoidea (^{Salinas-Gutiérrez et al., 2004}).

Species composition similarity across regions: We compared nymphalid faunal richness across eight regions with differing elevational gradients, comprising six from the Pacific slope and two from the Atlantic slope (Table 3). All regions have roughly similar sampling effort, and species estimation methods indicate that more than 90 % of the species have been recorded from each, thus validating the comparison. The Loxicha Region is the most diverse for Nymphalidae on the Pacific slope, and the second most diverse in Oaxaca, behind only the Sierra de Juárez (259 spp.) of the Atlantic slope. Identical patterns exist for Papilionidae and Pieridae (^{Luis-Martínez et al., 2020}).

Similarity analysis shows two main groups (Fig. 3), corresponding to the arrangement of mountain ranges in Mexico and the consequent isolation of the lepidopterofauna. The first group comprises the Sierra Mazateca and the Sierra de Juárez, on the Atlantic slope of Oaxaca. The second group is composed of six regions on the Pacific slope or in the Amacuzac-Cuenca del Balsas, which are divided into two subgroups with a similarity value of more than 50 %. The first subgroup contains the regions of the Southern Sierra Madre del Sur: Atoyac and Loxicha, which share 66 % of their species (142 spp.). The second subgroup corresponds to the regions located North of the Costa del Pacífico, in the Western Eje Neovolcánico (San Juan-Manantlán), the Northern Sierra Madre del Sur (SMS-Michoacán), and Morelos which includes parts of two biogeographic provinces: Cuenca del Balsas and Eje Neovolcánico.

Species composition distances between Loxicha and other regions are correlated with geographic distances, but also with biogeographic regionalization (Fig. 3). The two regions with the greatest faunistic distance are those from the Atlantic slope (the Sierra de Juárez and Sierra Mazateca), even though they are the closest geographically. The same pattern was observed with Morelos, which belongs to the Cuenca del Balsas: although Morelos is closer to Loxicha than regions like San Juan and Manantlán, these two have lower faunistic distances. Considering only the four regions in the SMS, faunistic distances are correlated with geographic distances, with Atoyac being the closest and most similar to Loxicha while also being the farthest and most distinct relative to San Juan.

Species richness by site: The MARIPOSA database contains records of Nymphalidae species from more than 5 000 sites across Mexico. However, only 40 of those sites have over 100 species recorded, eight of which are on the Pacific slope while the other 32 are distributed elsewhere in Mexico (Table 4). From the Loxicha Region, only Azulillo and Rancho Hagia Sofía exceed 100 species, placing them in sixth and fourth place at a national scale, respectively. Areas like Acahuizotla, Guerrero (158 spp.) and Candelaria Loxicha, Oaxaca (138 spp.) also have high species richness but are not specific sites, instead being extended areas that include several sites with wide variation in elevation and vegetation type. These extended or historical “sites'' served as geographic references for decades prior to this study, where collected specimens from other sites were gathered and labeled. Additional such historical “sites'' across Mexico include Xalapa, Catemaco, and Presidio in the state of Veracruz (^{Luis-Martínez et al., 1996}), Chiltepec, Oaxaca (^{Luis-Martínez et al., 1991}), and some others on the Atlantic slope.

Of the 40 sites with more than 100 species of Nymphalidae (Table 4), 16 have been sampled by members of the MZFC, and 30 are located in 11 of the regions with highest diversity of Papilionoidea in Mexico. Of these high-diversity regions, nine were recognized by ^{Luis-Martínez et al. (2003}): 1, Orizaba-Córdoba-Fortín de las Flores corridor; 2, Tuxtlas; 3, Xalapa-Coatepec-Teocelo corridor; 4, Sierra de Juárez; 5, Sierra de Atoyac; 6, Sierra de Manantlán; 7, Mismaloya-Bahía de Banderas corridor; 8, Acahuizotla; and 9, Sierra de San Juan. Recently, two more high-diversity regions were recognized: 10, La Sierra Norte de Puebla (MARIPOSA database), and 11, Loxicha (^{Arellano-Covarrubias et al., 2018}; ^{Luis-Martínez et al., 2016}; ^{Luis-Martínez et al., 2021}; data presented here).

Species composition similarity across sites: Of the 77 sites included in the species composition similarity analysis (Table 5), 62 are on the Pacific slope and 15 on the Atlantic slope, 44 have been sampled by members of the MZFC, 32 are located between 0-750 m, 27 between 800-1 750 m, and six above 1 800 m elevation. Five vegetation types are included: TDF, TSDF, OPF, OF, and CF. The latter includes three elevation-delimited subtypes: low-CF (750-1 199 m), medium-CF (1 200-1 800 m), and high-CF (> 2 000 m). Additionally, we recognize six ecotones: OF-CF, OPF-CF, TDF-TSDF, TDF-TSDF-CF, TSDF-CF and TSDF-OPF. Twenty-four sites are in the CF, and seven more exist in an ecotone that includes CF. Therefore, CF is the most well-represented vegetation type across the sites (48 % of the sites).

The similarity analysis showed two groups corresponding to the sites of the Atlantic and Pacific slopes, respectively (Fig. 4). Sites of the Atlantic slope, in the low part of the phenogram (1), are associated with the vegetation and environmental conditions of the Gulf of Mexico (East of Chiapas). This group has 163 exclusive taxa, six of which are distributed in 85 % of the sites of the group: Archaeoprepona demophon centralis (Fruhstorfer, 1905), Catonephele mexicana Jenkins & R. G. Maza, 1985, Fountainea eurypyle confusa (A. Hall, 1929), Hamadryas amphinome mexicana (Lucas, 1853), Morpho helenor montezuma Guenée, 1859, and Taygetis thamyra (Cramer, 1779). The second group comprises the sites in the Pacific slope (2), divided into four subgroups. In the first subgroup are the sites of the highlands of the Sierra de Atoyac de Álvarez (La Golondrina, El Iris, and Puerto del Gallo) (3). No exclusive species were recorded for these three sites. Interestingly, although these sites are geographically close to the sites of Balsas and SMS, they segregate from other sites of the Pacific because of their high-elevation species assemblage (1 800-2 350 m). In the second subgroup are the sites of the biogeographic provinces Costa del Pacífico, Northern Sierra Madre del Sur, and Western Eje Neovolcánico (4). Six species are exclusive to this subgroup: Bolboneura sylphis sylphis (Guérin-Méneville, 1844), Chlosyne rosita montana A. Hall, 1924, Cyllopsis pallens L. Miller, 1974, Fountainea halice tehuana (A. Hall, 1917), Polygonia interrogationis (Fabricius, 1798), and Texola elada hepburni (Godman, 1901), but all are restricted to just 4-12 % of the sites in the subgroup. A third subgroup is formed by the sites in the Balsas province of Guerrero and Morelos (6). These sites support mostly TDF and lie at elevations from 760-2 280 m. Of the three exclusive species to Balsas, Zischkaia lupita (Reakirt, (1867)) is in 79 % of the sites of this subgroup, while Chlosyne cyneas cynisca (Godman & Salvin, 1882) and Cyllopsis pertepida pertepida (Dyar, 1912) are documented only in 7 % of the sites. The fourth subgroup includes the Loxicha Region and is composed of the sites of Oaxaca and Guerrero in the SMS (5). Exclusive species recorded in at least 80 % of the sites of this subgroup are Archaeoprepona amphimachus baroni, Catonephele numilia immaculata, Diaethria astala asteroide, and D. anna mixteca. This subgroup is divided into two sets of sites: those with low-elevation CF, and those with TSDF between 350-900 m. However, the high-elevation site El Guajolote (2 202 m) is similar to these sites, possibly because of its geographical proximity. The other set of sites are those within the SMS with mid-elevation CF, between 600-1 600 m. A clear distinction exists between the sites of Oaxaca and those of Guerrero. These results show that the position of the sites in the phenogram corresponds to their geographic location but also to their respective elevations (Fig. 4).

Diversity of the Loxicha Region relative to other regions of the Sierra Madre del Sur and Costa del Pacífico: The Mexican Pacific slope, particularly in Guerrero and Oaxaca, stands out for its remarkable diversity and endemism at both the species and genus level. In this area, only two faunistic studies exist that cover a complete elevational gradient, and that have an inventory completeness level higher than 95 % according to the species richness estimators. The first study was carried out in the Sierra de Atoyac, Guerrero, from 300-3 100 m (^{Vargas-Fernández et al., 1994}) and the second one is the present study from 80-2 850 m (Table 6). Including both inventories, the diversity of Nymphalidae in the area is 214 species including 11 subfamilies and 84 genera. Of these 214 species, 88 % occur in the Loxicha Region and 78 % in the Sierra de Atoyac. Species richness is higher in Loxicha for nine of the 11 subfamilies, with the greatest difference being in Nymphalinae (11 sspp.); only Satyrinae has a higher species richness in the Sierra de Atoyac, with nine subspecies.

Considering both transects, 13 species endemic to Mexico were recorded: Pteronymia rufocincta, Cyllopsis caballeroi^{Beutelspacher, 1982}, C. clinas, C. diazi, C. jacquelineae, C. nayarit, C. perplexa L. Miller, 1974, Paramacera copiosa L. Miller, 1972, Taygetis uncinata, Catonephele cortesi, Chlosyne cynisca, Chlosyne eumeda (Godman & Salvin, 1894), and Phyciodes pallescens. At the subspecies level there are 66 endemics, constituting 31 % of the Nymphalidae recorded in these areas. At a national scale, Loxicha and the Sierra de Atoyac contain 43 % of the species or subspecies of Nymphalidae endemic to Mexico. Of these endemics, 56 are present in the Loxicha Region and 55 in the Sierra de Atoyac, with 64 % of the endemics shared between the two (^{Llorente-Bousquets, Trujano-Ortega et al., 2006}; ^{Luis-Martínez et al., 2003}; ^{Luis-Martínez et al., 2016}; ^{Luis-Martínez et al., 2021}). As with the endemics of the Loxicha Region, endemics of the Sierra de Atoyac were grouped into four categories: 1, endemic to the Sierra de Atoyac (3 sspp: Drucina championi ssp., Eunica malvina almae^{Vargas, Llorente & Luis, 1996}, and Eueides isabella nigricornis R. G. ^{Maza, 1982}); 2, endemic to the Sierra Madre del Sur (17 sspp.); 3, endemic to the Pacific slope (23 sspp.); and 4, endemic to Mexico (12 sspp.). These numbers are very similar to those of the Loxicha Region, with differences of at most three species. In both regions, Nymphalinae has the highest species richness and Biblidinae has most of the endemic taxa. Libytheinae, Danainae, and Apaturinae have the lowest richness, a common pattern in America (^{Lamas, 2004}; ^{Pelham, 2008}). Additionally, in Loxicha these three subfamilies have no endemic taxa.

Discussion

More than 60 % of Mexico's surface is covered by mountains, but faunal surveys of Lepidoptera across elevational gradients are scarce, except for those done by members of the MZFC (^{Arellano-Covarrubias et al., 2018}; ^{Luis-Martínez & Llorente-Bousquets, 1990}; ^{Luis-Martínez et al., 1991}; ^{Luis-Martínez et al., 2020}; ^{Vargas-Fernández et al., 1994}; ^{Vargas-Fernández et al., 1999}). This type of analysis provides important insight into various biological processes. Such insights include the recognition of disjunct distributions across mountain archipelagos due to speciation and endemism processes, and the ability to detect changes of species distribution due to climate change, especially in stenotopic species vulnerable to extinction.

Of all elevational gradients in Mexico, the Loxicha Region is the most systematically sampled area for Papilionoidea sensu lato, particularly for the Nymphalidae (Table 2). Many experienced collectors have sampled this region for decades (^{Álvarez-García et al., 2016}; ^{Arellano-Covarrubias et al., 2018}; ^{Luis-Martínez et al., 2000}; ^{Luis-Martínez et al., 2003}; ^{Luis-Martínez et al., 2020}; ^{Michán et al., 2004}; ^{Pozo et al., 2008}). Estimates of Nymphalidae species richness in the Loxicha Region show that it has the highest percentage of inventory completeness for any region in Mexico (^{Vargas-Fernández et al., 1994}; ^{Vargas-Fernández et al., 1999}). Furthermore, it has the highest species richness of any region on the Pacific slope (Table 1 and Table 3) and the second richest in the country, behind only the Sierra de Juárez (Table 3).

Sampling in the Loxicha Region began in 1960, based on historical specimens that we checked and on publications that described a dozen taxa from those specimens. However, even with Loxicha's great species richness and endemism, the present work is the first systematic study that provides a detailed regional description of the diversity and distributional patterns of Nymphalidae, mirroring similar works published previously for Riodinidae (^{Arellano-Covarrubias et al., 2018}), Papilionidae, and Pieridae (^{Luis-Martínez et al., 2020}).

Species richness of Nymphalidae by site: Comparison of the diversity on both the Pacific and Atlantic slopes confirms that the latter has higher species richness (v. gr.^{Andresen, 2008}; ^{Ceballos, 1995}; ^{Flores-Contreras & Luna-Reyes, 2017}; ^{González-Ramírez et al., 2017}; ^{Luis-Martínez et al. 2003}; ^{Salinas-Gutiérrez et al. 2004}). Of sites with 100 or more species of Nymphalidae, only 20 % are on the Pacific slope. Moreover, among these Pacific slope “sites'' are Acahuizotla, Guerrero and Candelaria Loxicha, Oaxaca, which are larger areas that historically encompassed a group of sites with distinct elevations and vegetation types but labeled under a single site name. These areas were used as reference points for collectors for three decades (1950-1980) of the 20^th century. Therefore, actual species richness of these reference sites is lower than cited, further reducing to 15 % the Pacific slope sites with over 100 species. In the last 40 years, more than 10 faunistic studies on Papilionoidea were done on the Pacific slope by members of the MZFC (^{Llorente-Bousquets et al., 1996}; ^{Llorente-Bousquets et al., 2004}; ^{Luis-Martínez & Llorente-Bousquets, 1993}; ^{Luis-Martínez, 1997}; ^{Luis-Martínez, 1999}; ^{Luis-Martínez, 2001}; ^{Vargas-Fernández et al., 1994}; ^{Vargas-Fernández et al., 1996}; ^{Vargas-Fernández et al., 1999}; ^{Warren & Llorente-Bousquets, 1999}; ^{Warren et al., 1996}; ^{Warren et al.,1998}), but only six sites exceed 100 species. Of these, only four are in Sierra Madre del Sur (two in the Sierra de Atoyac and two in the Loxicha Region), which is the mountain range with the greatest diversity on the Pacific slope despite lacking tropical evergreen forest vegetation. San Jerónimo, Tacaná, Chiapas is the only Mexican site with more than 100 species that lacks a systematic faunistic study; data from this site were obtained from national and international specimen collections (MARIPOSA database).

Species composition similarity across regions: The similarity analysis reflects how Lepidoptera are associated with mountain archipelagos, as described by ^{Llorente-Bousquets (1984}) and ^{Halffter (1987}). In Mexico, the states of Guerrero and Oaxaca support the most faunistically similar mountain habitat “islands'' (^{Llorente-Bousquets, 1984}). These two isolated regions each have exclusive or endemic species, yet they share at least 50 % of their species, forming geographic and genealogic relations between them. Other areas are disjunct, each with its own biogeographic history based on patterns of biotic provinces defined by ^{Morrone et al. (2002}) and ^{Morrone (2005}). The distinction between the diurnal Lepidoptera on the Atlantic and Pacific slopes had been further revealed using panbiogeographic methods (^{Llorente-Bousquets, Trujano-Ortega et al., 2006}; ^{Luis-Martínez et al., 2006}; ^{Oñate-Ocaña et al., 2006}; ^{Vargas-Fernández et al., 2006}).

The faunistic similarity of Nymphalidae shows a division in the Pacific slope and SMS in two parts, a Northwest section (Nayarit, Jalisco, Michoacán) and a Southeast section (Guerrero, Oaxaca), with the latter including the Loxicha Region. This division of the SMS in two subprovinces was proposed by ^{Santiago-Alvarado et al. (2016}) based on data from 32 species endemic to the SMS. No distribution was consistent with the SMS as a whole. Later, ^{Morrone (2017}) named and described three subprovinces in the SMS: the West subprovince with the Jalisciense and Jalisciense-Manantlán districts, the Central subprovince with the Michoacán district, and the Oriental subprovince comprising the Guerrerense and Tierras Altas de Oaxaca districts. Although Nymphalidae data do not reflect the separation of these three subprovinces, when analyzing the data at a site-level scale, Nymphalidae of the Southwest SMS are shown to be more similar to the Balsas province fauna than to the fauna of the Northeast SMS.

Species composition similarity of sites: Diurnal Lepidoptera associated with the CF at all elevational levels are an excellent model for the study of complex dispersion, vicariance, and speciation patterns, due to the disjunct distribution and isolation of this vegetation community (^{Rzedowski, 1978}). Generally, CF fauna distribution patterns are consistent with the geographic barriers that delimit each of the mountain ranges of Mexico. An integrated phylogeographic analysis that included birds, mammals, and plants concluded that the evolution of the biota of the CF in Mesoamerica resulted from a complex combination of distinct histories of range expansion, isolation, and biotic differentiation (^{Ornelas et al., 2013}). A similar process seems to have occurred with the Papilionoidea sensu lato and particularly with Nymphalidae, based on distribution patterns resolved by multiple studies (^{Llorente-Bousquets, 1984}; ^{Llorente-Bousquets & Escalante, 1994}; ^{Llorente-Bousquets & Luis-Martínez, 1998}).

Nymphalidae assemblages are closely related to vegetation type and elevation but are also influenced by geographic history and distance. Sites are grouped in six sets according to their similarity (Fig. 4). The first one corresponds to the Atlantic slope, while the other subgroups represent the diverse faunas of the Pacific slope distributed in distinct physiographic units and biotic provinces. These results concur with the data published in faunistic studies and generic reviews, describing the distribution of fauna in three elevational levels of the CF based on the proposal of ^{Llorente-Bousquets (1984}). Sites on the Pacific slopes (Fig. 4, subgroups 3 to 6) are grouped similarly to the elevational gradients (Fig. 3). The Sierra Madre del Sur (Guerrero and Oaxaca portion) (Fig. 4, subgroup 5) is more similar to the Cuenca del Balsas (Fig. 4, subgroup 6), than to the sites in the Costa del Pacífico, Northern Sierra Madre del Sur, and Western Eje Neovolcánico provinces (Fig. 4, subgroup 4). Notably, the sites above 1 800 m in the Sierra de Atoyac de Álvarez (Fig. 4, subgroup 3, La Golondrina, El Iris, and Puerto del Gallo) are separated from subgroups 4 and 6, and from the sites above 1 800 m in the Loxicha Region (Puente Arroyo “El Guajolote'' and San José del Pacífico, 1 km S), even though these two regions are geographically close. Puente Arroyo “El Guajolote'' is part of the subgroup of low elevation Guerrero-Oaxaca sites below 900 m, while San José del Pacífico is separated from other sites of the Sierra Madre del Sur, placed near the sites of the Cuenca del Balsas, as the most distinct site of this group. These similarity patterns of the high-elevation sites of Atoyac and Loxicha suggest that these are isolated communities, with a distinctive fauna, different from nearby low-elevation sites as well as from other high-elevation sites.

In general, the faunistic composition of Nymphalidae agrees with the biogeographic history of Mexico and its proposed provinces (^{Morrone, 2005}; ^{Morrone et al., 2002}). First, there is a clear distinction between the faunas of the Atlantic and the Pacific. At a finer scale, a division of the Sierra Madre del Sur into a Northern and Southern portion was recognized. Within the Southern portion of SMS, sites are grouped by elevation and vegetation type, with high elevation sites separated from the rest. Therefore, distribution patterns of Nymphalidae in Mexico are produced at large scales by historical elements and at smaller scales by ecological elements.

Phenology: In the Loxicha Region, the temporal distribution of Nymphalidae species richness and abundance is correlated directly with the summer-associated rainy season (Fig. 5), which is common in most of the regions in Mexico (^{Álvarez-García et al., 2016}; ^{Luis-Martínez & Llorente-Bousquets, 1990}; ^{Luis-Martínez & Llorente-Bousquets, 1993}; ^{Luis-Martínez et al., 1991}; ^{Vargas-Fernández et al., 1994}; ^{Vargas-Fernández et al., 1999}). In the Loxicha Region, nymphalid species richness and abundance are higher from July to October. This pattern is echoed in the Sierra de Juárez (Oaxaca), the Sierra de Atoyac (Guerrero), the Sierra de Manantlán (Jalisco-Colima), and the Sierra de San Juan (Nayarit), although the month with the highest species richness differs among the regions. In Loxicha, October had the highest richness. In comparison, September is the month with most species recorded in the Sierras de Juárez, Manantlán, and San Juan, while in the Sierra de Atoyac most species were recorded in July. As rainfall decreases so too does species richness, with April and May being both the driest months and having among the lowest species richness in all regions.

Diversity and abundance by vegetation type: Stenoic species of Nymphalidae have a wider distribution across different vegetation types (Table 8) than the stenoic species of Papilionidae, Pieridae, and Riodinidae, which mostly occur in the TSDF and CF (^{Arellano-Covarrubias et al., 2018}; ^{Luis-Martínez et al., 2020}). The elevational profiles (Fig. 8, Fig. 9, Fig. 10, Fig. 11, and Fig. 12) show that the stenoic species of both Satyrinae and Nymphalinae are characteristic of each vegetation type. In contrast, Charaxinae and Biblidinae lack stenoic species in the OPCF but are represented in the lower-elevation vegetation types. The TDF is the vegetation type with the fewest stenoic species, with only 11 characteristic species of four subfamilies: Charaxinae, 3 spp.; Satyrinae, 1 sp.; Apaturinae, 1 sp.; Biblidinae, 5 spp.; and Nymphalinae, 1 sp. Comparing with other families, Riodinidae has a single characteristic species of the TDF (^{Arellano-Covarrubias et al., 2018}). In Papilionidae only the TSDF has a significant number of stenoic species with five of the 10 species recorded, while the number of stenoic species of Pieridae does not differ among vegetation types (^{Luis-Martínez et al., 2020}).

The observed species richness and abundance of Nymphalidae show that the OPCF is the most diverse vegetation type. Although the estimated species richness for the OPCF is not significantly different from that of the CF and the TSDF, the OPCF abundance is lower, with nine exclusive species. Despite being originally considered a combination of two vegetation types (^{Luis-Martínez et al., 2020}), these nymphalid results support the recognition of the OPCF as a distinct ecological unit. We suggest the analysis of other taxonomic groups to further characterize this vegetation type. In comparison, the CF presented the highest number of exclusive species with 16 taxa, although the strong dominance of some species decreases its diversity to a value lower than that of the OPCF. Considering the diversity and exclusive species of Nymphalidae that they support, we recommend that the OPCF, CF, and the TSDF be considered conservation priorities.

Van Someren-Rydon traps: Fruit-feeding butterflies constitute approximately 50 % of all Nymphalidae species (^{Santos et al., 2011}). Similarly, other authors have reported 40-55 % of fruit-feeding Nymphalidae species from tropical forests, with some variation in the composition among the subfamilies (^{Daily & Ehrlich, 1995}; ^{DeVries & Walla, 2001}; ^{DeVries et al., 1999}; ^{Freire-Jr. et al., 2021}a; ^{Pinheiro & Ortiz, 1992}; ^{Uehara-Prado et al., 2004}; ^{Vargas et al., 1994}; ^{Vargas et al., 1999}). In the last two decades, this guild has been used in analyses of forest fragmentation, conservation, monitoring, community structure, and ecology, because these species are more easily sampled (^{Freire Jr., Oliveira, et al., 2021}a; ^{Freitas et al., 2003}; ^{González-Valdivia et al., 2016}; ^{Pozo, 2006}; ^{Pozo et al., 2005}; ^{Pozo et al., 2009}). The growing importance of this guild underscores the relevance of the Van Someren-Rydon trap efficiency and efficacy data presented here.

During our fieldwork, all species of Charaxinae, Morphinae, and Apaturinae were collected in traps, along with most species of Satyrinae (92 %) and Biblidinae (77 %). In contrast, only two species of Limenitidinae were collected in traps (13 %). Apparently, Limenitidinae are only occasional visitors to traps, probably looking for water as some Ithomiinae also do, since neither of these two subfamilies belong to the fruit-feeding guild (^{Meave del Castillo & Luis-Martínez, 2000}). Traps are especially useful for collecting Charaxinae because these species frequent open spaces above the forest canopy, while Satyrinae frequent the understory less than one meter above ground (^{Freire Jr., Ribeiro, et al., 2021}). Across all Nymphalidae, 19 % of the taxa were collected exclusively with this technique, and for 69 % of the species documented, 75 % of the specimens were trapped. We thus emphasize that Van Someren-Rydon traps are critical for accurately documenting the species richness, abundance, and elevational and vegetational distributions of Nymphalidae.

Ethical statement: The authors declare that they all agree with this publication and made significant contributions; that there is no conflict of interest of any kind; and that we followed all pertinent ethical and legal procedures and requirements. All financial sources are fully and clearly stated in the acknowledgements section. A signed document has been filed in the journal archives.