Neotropical Genus Research Articles

Mechanisms of Karyotypic Diversification in Ancistrus (Siluriformes, Loricariidae): Inferences from Repetitive Sequence Analysis.

Ancistrus is a highly diverse neotropical fish genus that exhibits extensive chromosomal variability, encompassing karyotypic morphology, diploid chromosome number (2n = 34-54), and the evolution of various types of sex chromosome systems. Robertsonian rearrangements related to unstable chromosomal sites are here described. Here, the karyotypes of two Ancistrus species were comparatively analyzed using classical cytogenetic techniques, in addition to isolation, cloning, sequencing, molecular characterization, and fluorescence in situ hybridization of repetitive sequences (i.e., 18S and 5S rDNA; U1, U2, and U5 snDNA; and telomere sequences). The species analyzed here have different karyotypes: Ancistrus sp. 1 (2n = 38, XX/XY) and Ancistrus cirrhosus (2n = 34, no heteromorphic sex chromosomes). Comparative mapping showed different organizations for the analyzed repetitive sequences: 18S and U1 sequences occurred in a single site in all populations of the analyzed species, while 5S and U2 sequences could occur in single or multiple sites. A sequencing analysis confirmed the identities of the U1, U2, and U5 snDNA sequences. Additionally, a syntenic condition for U2-U5 snDNA was found in Ancistrus. In a comparative analysis, the sequences of rDNA and U snDNA showed inter- and intraspecific chromosomal diversification. The occurrence of Robertsonian rearrangements and other dispersal mechanisms of repetitive sequences are discussed.

Taxonomic Novelties in Sapranthus (Annonaceae): a new large-sized species endemic to the mountain cloud forest of Central America

Sapranthus (Annonaceae) is a Neotropical genus comprising ten small tree species, most of which inhabit the tropical dry forests of Mexico and Central America. Morphological characteristics of these species are quite variable and taxonomically informative, but the morphological affinities among them have not been studied. A multivariate cluster analysis was carried out to infer the morphological affinities among all species of Sapranthus, and to establish the position of a new species, S. pinedai, a shade tree used in the coffee plantations of Guatemala and El Salvador. This new species, illustrated and described herein, is recognized by a unique combination of features identified through comparisons with morphologically similar taxa, and a preliminary assessment of the conservation status of the new species was calculated. The results presented here show that Sapranthus forms four morphological groupings in two main clusters. The new species is more similar to S. microcarpus and S. campechianus, but differs from both species by its essentially glabrous leaves, short pedicels, fewer carpels, greater number of ovules per carpel, biseriate ovules, larger sessile fruits with a thick testa, and by its several lunate to wedge-shaped seeds. These morphological groupings provides new insights into the understanding of the sectional classification of the genus Sapranthus, the geographic distribution of its species, and the morphological affinity of the new species.

Three new species of the Neotropical genus Hapigia Guenée from Brazil (Lepidoptera, Notodontidae, Heterocampinae)

Three new species of Hapigia Guenée, 1854, from Brazil and Ecuador, are described: H. postpallida Becker sp. nov., H. violacea Becker, sp. nov. and H. violetta Becker, sp. nov.

Taxonomic revision of the sexually dimorphic flies of the Neotropical genus Euepalpus Townsend, 1908 (Diptera: Tachinidae), with notes on sexual patches in Tachinini

Euepalpus Townsend, 1908 is a small Neotropical genus of bristle flies (Diptera: Tachinidae: Tachinini), which includes two valid species whose taxonomy is unclear, mainly because males and females are sexually dimorphic. Males exhibit a pair of sexual patches on the dorsal surface of abdominal tergite 5, an unusual feature in Tachinidae. Here, the genus is revised, including a key to species and detailed descriptions and illustrations of the type material and males and females of each species. The male and female terminalia of Euepalpus species are described for the first time. Finally, I discuss the occurrence and distribution of sexual patches in Tachinini.

Culm anatomy of the genus Otatea (Poaceae, Bambusoideae, Bambuseae, Guaduinae) as a contribution to Mexican species identification

Otatea is a Neotropical woody bamboo genus with thirteen described species. It is distributed from Mexico to Central America and northeastern Colombia. In Mexico, the archaeological evidence suggests that the culms of Otatea have been used for centuries by some ethnic groups. It is important to explore morphological and anatomical characters for species identification in woody bamboos as consequence of its monocarpic nature. Most studies on culm anatomy are centered on commercially used species describing their physical and mechanical properties. The aim of this work was to find culm anatomical characters with taxonomic value. To perform this, we collected internode samples from adult plants at mid culm of 15 specimens that represent 10 described species and two putative new species of Otatea. Our results include descriptions of culm anatomy at a cross section accompanied with images that detail all the structures measured and described. Additionally, we elaborate a key based on anatomical characters. This contribution is the first to explore culm anatomy of the genus Otatea in search for characters with taxonomic value, providing useful evidence for species identification, including samples from archaeological sites.

Revisiting the Taxonomy of Cylapocoris Carvalho, 1954 (Hemiptera: Miridae: Cylapinae) with Descriptions of Five New Species and Morphology-Based Phylogenetic Analysis of the Genus.

This paper provides descriptions of five new species of the Neotropical genus Cylapocoris Carvalho, 1954 (C. bimaculatus n. sp., C. brooksi n. sp., C. carvalhoi n. sp., C. scutellatus n. sp., and C. simplexoides n. sp.). Cylapocoris and Cylapocoroides Carvalho, 1989 are redescribed and rediagnosed. Illustrations of male genitalia, scanning electron micrographs of selected structures of certain taxa, and an identification key to species are provided. Female genitalia are described and illustrated for the first time for Cylapocoris in nine out of 19 known species. A cladistic analysis of the genus, based on 62 morphological characters, is presented as a contribution to the understanding of relationships within Cylapocoris and its relationships with other groups of Cylapinae. The analysis comprises 16 ingroup species and 15 outgroup taxa. Both equal and implied weighting parsimony analyses were used in the phylogenetic reconstruction. We confirm the monophyly of Cylapocoris and its sister-group relationship with Cylapocoroides. Additionally, we identify subgroupings within Cylapocoris. Intertribal relationships within Cylapinae are briefly discussed.

Eight new species of Costanana DeLong & Freytag (Hemiptera: Cicadellidae: Gyponini): taxonomic changes, key to males, and description of Metacostana gen. nov.

Costanana DeLong & Freytag, 1972 is a Neotropical genus of leafhoppers currently comprising 13 species with a wide distribution from Mexico to Argentina. In this study, eight new species of Costanana are described, C. xenomorpha sp. nov. from Department of Cuzco, Peru, and seven Brazilian species: C. alata sp. nov. from Minas Gerais State; C. bifida sp. nov. from Paraná and Mato Grosso states; C. cifi sp. nov., C. obtusa sp. nov. and C. piraquarensis from Paraná State; C. luzi sp. nov. from Distrito Federal; and C. rubromarginata sp. nov. from Mato Grosso and Pará states. We propose that Costanana cella DeLong & Freytag, 1972 is a junior synonym of C. praecellens (Stål, 1862) and C. asymmetrica DeLong & Freytag, 1972 is a junior synonym of Gypona viridans DeLong & Martinson, 1972. Costanana costata DeLong & Freytag, 1972 and C. flavicosta (Stål, 1862) are transferred to Gypona Germar, 1821, C. minuta (Spångberg, 1878) is transferred to Acuponana DeLong & Freytag, 1970 and Gypona nupera Van Duzee, 1907 is transferred to Costanana. Gypona costata comb. nov. and Costanana santana DeLong & Wolda, 1983 are newly recorded from Pernambuco State, and Gypona flavicosta comb. nov. is recorded from Espírito Santo and Paraná states, Brazil. The female genitalia of Costanana flavina DeLong & Freytag, 1972, C. praecellens and Gypona flavicosta comb. nov. are described and illustrated for the first time and a brief note on feeding behavior is given for C. flavina and C. praecellens. A key to males and a new diagnosis are provided for Costanana. We also describe and illustrate Metacostana cornuta gen. et sp. nov., a new Brazilian genus for Gyponini sharing characteristics with Costanana, Acuthana Domahovski & Cavichioli, 2018, Domahovana Silva et al., 2022 and Dumorpha DeLong & Freytag, 1975.

Phylogenetic relationships of Cuban and Caribbean Plumeria (Apocynaceae) based on the plastid genome

Abstract Plumeria L. (Apocynaceae) is a Neotropical genus mostly restricted to the Caribbean, which is cultivated in tropical gardens worldwide. Almost all ~27 species are endemic to the Caribbean Islands, except for four (Plumeria inodora Jacq., Plumeria obtusa L., Plumeria pudica Jacq., and Plumeria rubra L.) that are native to Central America and northern South America. Cuba harbours the largest diversity of the genus, with 13 endemic species. We present the first molecular phylogeny of the genus based on the nucleotide sequences of the complete plastid genome. Partial plastid genomes of 11 Plumeria species and one closely related species (Himatanthus sp.) were sequenced using long-PCR and next-generation sequencing. The recovered clades mostly grouped by single islands or closely neighboring islands. The phylogenetic relationships indicate patterns of adaptive radiation, with ecological shifts within these island-based clades and a west-to-east colonization route in the region. Plumeria rubra and Himatanthus sp. were resolved as sister to the rest of the genus. One unexpected finding was that P. pudica, a species restricted to the southern Caribbean Basin mainland, was recovered within the clade containing the Caribbean Island endemics, rendering the endemic group polyphyletic. Our study provides a phylogenetic framework for future studies that will need to include nuclear molecular markers and a more extensive sampling.

The genus Malanea Aubl. (Rubiaceae) in the Atlantic Forest of Brazil

Background and aims – Malanea (Rubiaceae) is a Neotropical genus of ca 40 species, 15 of which occur in Brazil, with nine found in the Atlantic Forest domain. This study aims to present a taxonomic treatment of the species occurring in the Atlantic Forest domain. Material and methods – We studied collections deposited in 15 Brazilian herbaria, ALCB, BHCB, BHZB, CEPEC, HUEFS, HUFU, IPA, JPB, MAC, OUPR, PEUFR, RFA, RB, UFP, and UFRN, and collections in NY were studied online. Specimens were identified using protologues and digital images of types available online. Key results – Of the nine species of Malanea previously recognized in the Atlantic Forest domain, we accepted seven, six of which are endemic. Malanea macrophylla has a wide distribution also occurring in other Brazilian phytogeographic domains, and adjacent countries. We expanded the distribution of four species and identified Bahia as the possible centre of diversity for the group in the domain. In addition, an identification key to the species, detailed descriptions, taxonomic notes, typifications, illustrations, maps of geographic distribution, and assessments of conservation status are provided. The names Malanea evenosa, M. forsteronioides, M. macrophylla, M. martiana, and M. spicata are here typified. The calculated conservation status revealed three Endangered species, two Vulnerable ones, M. forsteronioides as Near Threatened, and M. macrophylla with a status of Least Concern.

Leaf morphology and anatomy in Myrcia sect. Aulomyrcia (Myrtaceae): species circumscription and characterization of clades

Myrcia DC., a diverse neotropical genus of Myrtaceae, encompasses 793 species. However, species of Myrcia are similar and difficult to distinguish. In Myrcia sect. Aulomyrcia (O. Berg) Griseb., leaf features help distinguishing clades and species. Our aim is to provide leaf data for species of M. sect. Aulomyrcia’s clades F and G. We sampled 31 specimens of 13 species of Myrcia sect. Aulomyrcia ( Myrcia amazonica DC., Myrcia eumecephylla (O. Berg) Nied., Myrcia hexasticha Kiaersk., Myrcia insularis Gardner, Myrcia magna D. Legrand, Myrcia micropetala (Mart.) Nied., Myrcia neodimorpha E. Lucas & C.E. Wilson, Myrcia neoestrellensis E. Lucas & C.E. Wilson, Myrcia obversa (D. Legrand) E. Lucas & C.E. Wilson, Myrcia pyrifolia (Desv.) Nied., Myrcia riodocensis G.M. Barroso & Peixoto, Myrcia subobliqua (Benth.) Nied., and Myrcia tetraphylla Sobral) . Samples were subjected to sectioning and staining techniques for morphological and anatomical analysis through stereo and light microscopy. Leaf blade and petiole morphological and anatomical features were described carefully for the first time for these 13 species. We provided an identification key based on leaf features. Our findings are discussed in the light of Myrcia sect. Aulomyrcia systematics. We comment of the significance of petiolar and blade features, such as trichomes types and location, phyllotaxis, rhytidome peeling, periderm and lenticels, and petiole, blade, and vascular cylinder shape. Our study brings novel information on leaf structure variation in Myrcia sect. Aulomyrcia, delivering much needed data for species and clades circumscription and identification.

Rediscovery of Histiotusalienus Thomas, 1916 a century after its description (Chiroptera, Vespertilionidae): distribution extension and redescription.

Histiotus is a Neotropical genus of bat that currently includes 11 species. The systematics of Histiotus has been the focus of several studies over the last decades. However, no broad systematic revision has been made, and taxonomic issues such as synonymies, use of subspecies, and specimens that do not fit the description of valid species still persist, as pointed out by several authors. Histiotusalienus was described in 1916 and is known only by the holotype. Here we present a second record of H.alienus and an amended diagnosis of this species. We use qualitative, quantitative, and morphometric analyses based on data from 184 specimens of Histiotus and almost all valid species. Our amended diagnosis establishes the taxonomic limits of H.alienus, as well as a comprehensive comparison with congeners. We also explore new diagnostic characters for H.alienus and provide a few notes on the natural history of this species. Our results highlight skull similarities among Histiotus species and reinforce the usefulness of external morphology for their correct identification. Despite our new insights into the taxonomy of the genus, several taxonomic issues remain, and a comprehensive revision of the genus is needed.

Mastigodiaptomus galapagoensis n. sp. (Crustacea: Copepoda: Diaptomidae), a possibly extinct copepod from a crater lake of the Galápagos archipelago.

A new species of a Neotropical diaptomid copepod is described based on individuals recovered from a small, almost forgotten collection of unique plankton samples from El Junco, a crater lake in San Cristóbal island, Galápagos archipelago. This copepod was regularly reported (1966-2004) as an abundant zooplankter in the lake, but it was not found in subsequent plankton surveys (2007-2018), and its specific identity remained unknown. In 2020, it was declared extinct because of introduced fish predation, rotenone treatment, and other major disturbances. The taxonomic examination of these invaluable specimens allowed us to recognize them as representing an undescribed species of the freshwater diaptomid genus Mastigodiaptomus Light, 1939. Here, we describe the new species from El Junco crater lake, located in the San Cristóbal island a part of the Galápagos archipelago, collected with plankton nets. The description is based on detailed morphology, based on SEM and light microscopy. The taxonomic examination of these invaluable specimens allowed us to recognize them as representing an undescribed species of the freshwater diaptomid genus Mastigodiaptomus Light, 1939. The new species was readily assigned to this genus and is distinguished from its known congeners by details of (1) the male right fifth leg terminal claw and aculeus, (2) spiniform processes pattern of the right geniculate antennule segments 10-16, (3) length and structure of the spiniform process of the antepenultimate segment of the male right antennule, and (4) details of the dorsal process on the female fourth pediger. This finding represents the first report of this Neotropical copepod genus outside its original biogeographic region, the third species of a diaptomid copepod reported from insular freshwater systems, the southernmost record of Mastigodiaptomus, and the only freshwater calanoid in the Galápagos. The intriguing presence of this chiefly Neotropical copepod genus here could be related either to (1) human agency linked to pirate activities, commercial travelling by Spaniard ships, whaling activities, and intense tortoise hunting in San Cristóbal island. In the past, El Junco was the only freshwater source 600 nautical miles around, or (2) zoochory of resistant dormant stages passively transported by more than 65 migrating bird species known to settle in San Cristóbal. These two hypotheses cannot be properly tested at this time, so the explanation of the presence of this copepod will remain as a new open question in the fascinating natural history of the Galápagos.

The underestimation and evolutionary significance of post-imaginal growth in the termitophilous Termitogastrina: Insights from a new species of Xenogaster from Brazil (Staphylinidae: Aleocharinae: Corotocini)

Xenogaster Wasmann is a Neotropical genus of termitophilous rove beetles with 11 known species. During recent surveys in Southeastern Brazil, we collected a new species of this genus, Xenogaster lugens Pires-Silva and Zilberman sp. nov., herein described. This new species is known only from an intermediate stage of development, which prompted a discussion about the range and underestimation of the phenomenon of post-imaginal growth in Termitogastrina (Corotocini). A redescription of X. pilosula Seevers, and comparisons between its stenogastric and physogastric stages are also presented and used in the final discussion on the taxonomical and evolutionary significance of this phenomenon under the frame of the knowledge of post-imaginal growth in the subtribe and also Corotocini in general.

Structure and ontogeny of inflorescence and flower of Bactris acanthocarpoides Barb. Rodr. and Bactris hirta Mart. (Arecaceae, Arecoideae, Bactridinae)

Bactris is a Neotropical genus of high floristic importance, which needs morphological data to support the construction of a correct infrageneric classification. In this research, the inflorescences and flowers of Bactris acanthocarpoides Barb and B. hirta Rodr. Mart., are morphoanatomically characterised and the floral ontogeny in each of these taxa is presented in order to provide useful biological information that contributes to such classification. The results are analyzed in the context of reproduction and evolution of the palms. To achieve this, we use light and scanning electron microscopy. The distribution of appendages on the prophyll, the development of staminodes in the pistillate flowers of B. acanthocarpoides, the presence of tector trichomes on the sepals of this species, the greater scleromorphism and the presence of papillose exothecium in B. hirta, as well as the location of the vascular bundles in the perianth parts, are characters that allow distinguishing the taxa. The ontogenetic study reveals the acropetal development of the inflorescences, as well as the formation of one subtending bract for each flower of the triad and one for each triad; likewise the sequence of centrifugal development of the stamens and the formation of the gynoecium synascidiate at the base and simplicate at the top. Additionally, the histological arrangement of each floral organ was characterized and all the appendages observed were described.

Taxonomic Revision of Bredemeyera (Polygalaceae)

Abstract— Bredemeyera is a neotropical genus that comprises 12 species of woody vines and sub-erect or scandent shrubs. It occurs from Mexico to Paraguay and nearly all over Brazil. In this paper, we present a complete taxonomic revision of the genus. Bredemeyera ericifolia, a new species from the Brazilian state of Piauí, is here described and illustrated. Lectotypes are designated for Bredemeyera bracteata, B. densiflora, B. densiflora var. glabra, B. floribunda var. puberula, B. huberiana, B. isabelliana, B. laurifolia var. parvifolia, B. myrtifolia, B. parviflora, Catacoma altissima, C. brevifolia, C. lucida, and Securidaca flexuosa. A [second-step] lectotype is designated for B. velutina. Here, the names Bredemeyera altissima and B. lucida are considered taxonomic synonyms of B. divaricata, whereas B. myrtifolia and B. densiflora are synonyms of B. bracteata, and finally, B. disperma is considered a synonym of B. laurifolia. We provide an identification key, descriptions, distribution maps, illustrations, and comments on the conservation status, nomenclature, and taxonomy of all species involved.

Review of Trigona (Nostotrigona) Engel, 2021 from Brazil with description of three new species (Hymenoptera: Apidae: Meliponini).

Trigona Jurine, 1807 (Hymenoptera: Apidae: Meliponini) is a Neotropical genus of stingless bees that is most diverse in the Amazon biome. The subgenus T. (Nostotrigona) was recently described and contains the taxa of the T. recursa species-group. In the present study, three new species of this subgenus are described: T. daianeae sp. nov., T. juvenili sp. nov., and T. mandaloriana sp. nov., including new records of T. permodica Almeida, 1992 for Brazil. A distribution map for T. (Nostotrigona) species are also provided.

Geographical distribution and notes on the nests of the “uruçu-do-chão” bee, Melipona (Melikerria) quinquefasciata Lepeletier, in Bahia, North-eastern Brazil

The Neotropical genus of stingless bees Melipona Illiger, 1806 is exclusive to Tropical America and has its greatest diversity in South America, with about 74 described species. In Bahia, there is an occurrence record for 12 species of Melipona, distributed in four subgenera. Among the Melipona (Melikerria) that occur in Bahia, we highlight Melipona (Melikerria) quinquefasciata Lepeletier, 1836. Although widely distributed in Brazil, its underground nesting habit associated with its preference for high altitude areas, make the species extremely vulnerable. This work sought to describe nests and map the occurrence of this species for the State of Bahia, since its record is limited to areas of Chapada Diamantina. Knowledge about the biogeography of the species is extremely important, strengthening its sustainable creation that respects the area of ​​occurrence of the species, as well as seeking alternatives and public policies for sustainable conservation, since its area of ​​occurrence is extremely vulnerable to the expansion of the agricultural frontier in the State.

The Neotropical antlion genus Ameromyia Banks, 1913 (Neuroptera: Myrmeleontidae), systematics and redefinition under a phylogenetic approach

A taxonomic revision and the first phylogenetic hypothesis of the Neotropical genus Ameromyia Banks (Myrmeleontidae: Brachynemurini) is herein presented. The phylogeny is based on 45 morphological characters and recovered the traditional Ameromyia as paraphyletic in respect to the monotypic genus Venezueleon Stange, which is here synonymized under Ameromyia. Three species are synonymized (A. hirsuta Navás and A. stevensi Navás under A. nigriventris (Walker), and A. pentheri Navás under A. strigosa (Banks)) and two new species are described (A. clepsydrasp. nov. and A. explicatasp. nov.). Ameromyia sensu novo is a valid genus with 12 species restricted to South America, and divided into two species groups. Taxonomic keys are also presented to adults and larvae, as well as a discussion on the genus biology.

The First Record of Calvolia summersi (Mostafa, 1970) (Acari: Winterschmidtiidae) from the Oriental Region and a new record of host association with Xylocopa (Ctenoxylocopa) fenestrata (Fabricius, 1798) with a review on Xylocopa-mite associations in India

Mites have long been associated with bees, often showing a close relationship with particular taxa, probably due to a co-evolutionary process. The present study is the first confirmation on the occurrence of the mite species Calvolia summersi (Mostafa, 1970) in India and its association with Xylocopa fenestrata (Fabricius, 1798), a large carpenter bee species. The mite species was previously reported from Brazil in association with Zethus, a neotropical potter wasp genus. C. summersi is isolated and studied from different populations of X. fenestrata in Sagar Islands, West Bengal, the biggest island of mangrove Sundarban deltaic complex. A literature-based review of the Xylocopa-mite associations from India is provided herewith to understand the diversity and pattern of mite species on Xylocopa host selection in the country. Instigating a baseline study of Xylocopa-mite association is recommended to demark the status of dynamism for better conservation and protection.

The Trichoptera of Panama XXI. Review of the genus Tizatetrichia Harris, Flint, and Holzenthal, 2002 (Trichoptera: Hydroptilidae), including two new species, one first country record, and female description of T. panamensis Harris and Armitage, 2019

The genus Tizatetrichia Harris, Flint, and Holzenthal, 2002 (Trichoptera: Hydroptilidae) was described based on a single male of T. costatricensis Harris, Flint, and Holzenthal, 2002 collected from Guanacaste Province in northwestern Costa Rica. Since then, the second species (T. panamensis Harris and Armitage, 2019) was discovered in a small Caribbean drainage near Chiriquí Grande, Panama. No female of this genus had been described. Recent collections carried out by the Aquatic Invertebrate Research Group (AIRG) at the Universidad Autónoma de Chiriquí (UNACHI) now expand our knowledge of this genus. Herein, we describe a female of Tizatetrichia for the first time, comparing it with that of the related genus Bredinia Flint, 1968. In addition, we describe two new species from central and western Panama (T. escabrosa sp. n. and T. paloseco sp. n.), report one first country record (T. costaricensis), provide keys to the identification of Stactobiinae genera and Tizatetrichia species, and discuss the distribution of the genus in relation to altitude. Panama is now the home to all four species of this Neotropical genus, and its endemic status expanded to Central America. The Republic of Panama has 490 species of caddisflies distributed among 15 families and 56 genera.