The ticking clock in the dark: Review of biological rhythms in cave invertebrates.

Circadian clocks, internal mechanisms that generate 24-hour rhythms, play a crucial role in coordinating biological events with day-night cycles. In light-deprived environments such as caves, species, particularly isolated obligatory troglobites, may exhibit evolutionary adaptations in biological rhythms due to light exposure. To explore rhythm expression in these settings, we conducted a comprehensive literature review on invertebrate chronobiology in global subterranean ecosystems, analyzing 44 selected studies out of over 480 identified as of September 2023. These studies revealed significant taxonomic diversity, primarily among terrestrial species like Coleoptera, with research concentrated in the United States, Italy, France, Australia, and Brazil, and a notable gap in African records. Troglobite species displayed a higher incidence of aperiodic behavior, while troglophiles showed a robust association with rhythm expression. Locomotor activity was the most studied aspect (>60%). However, approximately 4% of studies lacked information on periodicity or rhythm asynchrony, and limited research under constant light conditions hindered definitive conclusions. This review underscores the need to expand chronobiological research globally, encompassing diverse geographical regions and taxa, to deepen our understanding of biological rhythms in subterranean species. Such insights are crucial for preserving the resilience of subsurface ecosystems facing threats like climate change and habitat loss.

Environmental Drivers of the Moonmilk Microbiome Diversity in Some Temperate and Tropical Caves.

Moonmilk is a cave deposit that was used for medical and cosmetic purposes and has lately raised interest for its antimicrobial potential. We studied five moonmilk samples from four caves with different microclimatic conditions, two temperate in north-western and northern Romania (Ferice, Fața Apei, and Izvorul Taușoarelor caves) and one tropical in Minas Gerais, Brazil (Nestor Cave). The physicochemical and mineralogical analyses confirmed the presence of calcite and dolomite as the main phase in the moonmilk. A 16S rRNA gene-based metabarcoding approach showed the most abundant bacteria phyla Proteobacteria, GAL15, Actinobacteriota, and Acidobacteriota. The investigated caves differed in the dominant orders of bacteria, with the highest distance between the Romanian and Nestor Cave samples. Climate and, implicitly, the soil microbiome can be responsible for some differences we found between all the samples. However, other factors can be involved in shaping the moonmilk microbiome, as differences were found between samples in the same cave (Ferice). In our five moonmilk samples, 1 phylum, 70 orders (~ 36%), and 252 genera (~ 47%) were unclassified, which hints at the great potential of cave microorganisms for future uses.

A Highly Troglomorphic New Genus of Sminthuridae (Collembola, Symphypleona) from the Brazilian Semiarid Region.

Here, we describe the highly troglomorphic Troglobentosminthurus gen. nov. from Água Clara cave system, Caatinga domain, Bahia, Brazil. Troglobentosminthurus luridus gen. nov. sp. nov. has remarkably long antennae, legs and furca, and lacks body pigments, except for small orange eye patches which also show a reduction in the number of eyes (5 + 5) and lens sizes. The overall morphology of the genus, with long and highly sub-segmented antennae, resembles other Sminthurinae of the Temeritas-group, especially Temeritas Richards and Galeriella Curcic and Lucic. However, it is unique, especially in the combination of the number of antennae IV subsegments and eyes, frontal head chaetotaxy and empodial complex morphology. Two type specimens have remnants of a mite and another specimen from the new species in their gut contents, supporting the species may be occasional predators and even cannibals. We also provide identification keys and comparative tables to the subfamilies of Sminthuridae and the Temeritas-group of genera.

Cave conservation priority index to adopt a rapid protection strategy: a case study in Brazilian Atlantic rain forest.

Cave environments are characterized by possessing specialized fauna living in high environmental stability with limited food conditions. These fauna are highly vulnerable to impacts, because this condition can frequently be easily altered. Moreover, environmental determinants of the biodiversity patterns of caves remain poorly understood and protected. Therefore, the main goal of this work is to propose a cave conservation priority index (CCPi) for a rapid assessment for troglobiotic and troglophile protection. Furthermore, the troglobiotic diversity, distribution and threats have been mapped in the Brazilian Atlantic forest. To propose the CCPi, the human impacts and richness of troglobiotic and troglophile species of 100 caves were associated. Data related to troglomorphic/troglobiotic fauna from another 200 caves were used to map the troglobiotic diversity and distribution. The CCPi reveals extremely high conservation priority for 15% of the caves, high for 36% and average for 46% of the caves. Fourteen caves with extremely high priorities should have urgent conservation and management actions. The geographical distribution of the 221 known troglobiotic/troglomorphic species allowed us to select 19 karst areas that need conservation actions. Seven areas were considered to have urgent priority for conservation actions. The two richest areas correspond to the "iron quadrangle" with iron ore caves (67 spp.) and the "Açungui limestone group" (56 spp.). Both areas have several caves and are important aquifers. The use of the CCPi can prevent future losses because it helps assessors to select caves with priorities for conservation which should receive emergency attention in relation to protection, management and conservation actions.

Nidificação de vespas e abelhas solitárias (Hymenoptera: aculeata) na reserva biológica Boqueirão, Ingaí, Minas Gerais / Nesting of solitary wasps and bees (Hymenoptera: aculeata) in the biological reserve Boqueirão, Ingaí, Minas Gerais

Durante um período de 21 meses (fevereiro/08 a outubro/09) avaliou-se as freqüências de nidificação de vespas e abelhas solitárias, o parasitismo associado às suas espécies e invasores de seus ninhos na Reserva Biológica Unilavras Boqueirão, Ingaí, MG (21º 14' 59" S / 44º 59' 27" W). As espécies foram amostradas por meio de ninhos-armadilha. As armadilhas foram confeccionadas em gomos de bambu, instalados em hastes de PVC e dispostos em transectos a cinco metros eqüidistantes. Em cada haste foram fixados três ninhos nas alturas de 0,56 m, 1,13 m e 1,70 m do solo nas fitofisionomias de Mata Ciliar, Cerrado stricto sensu e Borda de Mata. Os ninhos foram inspecionados quinzenalmente. Foram fundados 221 ninhos pertencentes a seis espécies de vespas e três de abelhas. Destes, 123 ninhos foram colonizados no Cerrado stricto sensu, 51 na Borda de Mata Ciliar e 47 no interior da Mata Ciliar. Três espécies predominaram nas áreas: Isodontia sp. (35% do total de ninhos fundados), seguida por Trypoxylon (Trypargilum) lactitarse Saussure (15%) e Centris (Hemisiella) tarsata Smith (11%). Intensa atividade de nidificação foi observada principalmente na estação quente e chuvosa (novembro-fevereiro). Um total de 29% dos ninhos foi parasitado por espécies de Chrysididae, Ichneumonidae e Bombyliidae. De modo geral os aspectos estruturais dos ninhos coletados nesse trabalho assemelham-se àqueles obtidos em estudos realizados com essas espécies em outros ambientes.

During a period of 21 months (February/2008 to October/2009) we evaluated the nesting frequencies of solitary wasps and bees, the parasitism associated with them, and the invaders of their nests in the Biological Reserve of the Unilavras Boqueirão, Ingaí, MG (21º 14' 59" S / 44º 59' 27" W). The species were sampled using trap nests. The traps were made of bamboo sections, fixed in PVC rods and placed in transects, five meters equidistant. On each rod, three nests were fixed on the heights of 0.56 m, 1.13 m and 1.70 m from the ground, in the following vegetation types: Riparian Forest, Cerrado stricto senso and Riparian Forest edge. Nests were inspected every two weeks. 221 nests were founded, belonging to six species of wasps and three species of bees. From all nests, 123 nests were founded in the Cerrado stricto sensu, 51 in the edge of the Riparian Forest and 47 within the Riparian Forest. Three species were abundant in all areas: Isodontia sp. (35% of total nests), followed by Trypoxylon (Trypargilum) lactitarse Saussure (15%) and Centris (Hemisiella) tarsata Smith (11%). Intense nesting activity was observed mainly in the hot, rainy season (November to February). A total of 29% of nests were parasitized by species of Chrysididae, Ichneumonidae and Bombyliidae. In general, the structural aspects of the nests collected in this study are similar to those obtained in studies with these species in other environments.

Aspects of the behavior and reproduction of Mastigoproctus brasilianus Koch, 1843, (Arachnida: Uropygi: Telyphonidae) / Aspectos do comportamento e reprodução de Mastigoproctus brasilianus (Koch, 1843)

A ordem Uropygi inclui aracnídeos sul tropicais predadores que apresentam pedipalpos raptoriais, um longo e multissegmentado pós-pigídio, e longo flagelo. O objetivo do presente trabalho foi avaliar o repertório comportamental de Mastigoproctus brasilianus (Koch 1843) em condições de laboratório, bem como descrever as diferentes formas de comportamentos envolvidos no ritual de acasalamento. Foram computados 25 atos comportamentais espontâneos. Os mesmos foram agrupados em 9 categorias que incluem: manter-se abrigado, permanecer imóvel, mover os apêndices sem deslocamento, extensão das pernas, limpar-se, mover-se com deslocamento (para frente ou para trás), cavar; se alimentar, "outras formas de comportamento" menos frequentes. As categorias de comportamentos diferiram entre os sexos e entre períodos de atividade. Os comportamentos dos machos diferem dos imaturos e das fêmeas adultas. O comportamento reprodutivo apresentado por M. brasilianus segue os padrões descritos para outras espécies.(AU)

The order Uropygi includes south tropical predator arachnids with large raptorial pedipalps, a long and multi-segmented pos-pygidium, and long flagellum. The aim of the present work is to evaluate the behavior repertoire of Mastigoproctus brasilianus (Koch 1843) in laboratory conditions, as well as describing the different forms of behavior involved in the mating ritual of this species. A total of 25 behavioral acts were witnessed, that were clustered in 9 categories which included: to remain sheltered; to remain immobile; to move appendices without displacement; extensioning the legs; to clean itself; to move (forward or backward); to dig; to feed and "other forms of behavior". The categories of behaviors varied between sexes and between periods of activity. Males differed from all the others and the females presented a similar pattern when compared to the immature forms. The reproductive behavior presented by M. brasilianus follows the standards described for other species(AU)

Aspects of the behavior and reproduction of Mastigoproctus brasilianus Koch, 1843, (Arachnida: Uropygi: Telyphonidae) / Aspectos do comportamento e reprodução de Mastigoproctus brasilianus (Koch, 1843)

A ordem Uropygi inclui aracnídeos sul tropicais predadores que apresentam pedipalpos raptoriais, um longo e multissegmentado pós-pigídio, e longo flagelo. O objetivo do presente trabalho foi avaliar o repertório comportamental de Mastigoproctus brasilianus (Koch 1843) em condições de laboratório, bem como descrever as diferentes formas de comportamentos envolvidos no ritual de acasalamento. Foram computados 25 atos comportamentais espontâneos. Os mesmos foram agrupados em 9 categorias que incluem: manter-se abrigado, permanecer imóvel, mover os apêndices sem deslocamento, extensão das pernas, limpar-se, mover-se com deslocamento (para frente ou para trás), cavar; se alimentar, "outras formas de comportamento" menos frequentes. As categorias de comportamentos diferiram entre os sexos e entre períodos de atividade. Os comportamentos dos machos diferem dos imaturos e das fêmeas adultas. O comportamento reprodutivo apresentado por M. brasilianus segue os padrões descritos para outras espécies.

The order Uropygi includes south tropical predator arachnids with large raptorial pedipalps, a long and multi-segmented pos-pygidium, and long flagellum. The aim of the present work is to evaluate the behavior repertoire of Mastigoproctus brasilianus (Koch 1843) in laboratory conditions, as well as describing the different forms of behavior involved in the mating ritual of this species. A total of 25 behavioral acts were witnessed, that were clustered in 9 categories which included: to remain sheltered; to remain immobile; to move appendices without displacement; extensioning the legs; to clean itself; to move (forward or backward); to dig; to feed and "other forms of behavior". The categories of behaviors varied between sexes and between periods of activity. Males differed from all the others and the females presented a similar pattern when compared to the immature forms. The reproductive behavior presented by M. brasilianus follows the standards described for other species

Seasonal Abundance and Species Composition of Flower-Visiting Flies / Composição, Abundância e Sazonalidade de Dípteros Visitantes Florais

Foram registradas, na Estação Ecológica da Universidade Federal de Minas Gerais (UFMG), espécies de moscas que visitam flores para se alimentar. Asteraceae, Rhamnaceae, e Boraginaceae foram as famílias mais visitadas. Asteraceae foi a mais rica em espécies floridas, sendo também a mais visitada por famílias e espécie de moscas. A diversidade mais elevada de visitantes ocorreu em Baccharis trinervis (Lam.) (H'=1.86). As famílias de moscas mais diversas foram Syrphidae (H' = 2,07) e Bombyliidae (H' = 1,52). Os sirfídeos Ornidia obesa (L.) e Palpada furcata (Wied.) foram as espécies mais abundantes entre as visitantes. A abundância total de visitantes foi significativamente maior na estação chuvosa, quando um número maior de plantas estavam florescendo. Entretanto, um maior número de famílias visitou plantas durante a estação seca. O número de fêmeas em quatro famílias de moscas foi ligeiramente mais elevado do que o número de machos. Calliphoridae e Sarcophagidae mostraram padrões similares com relação ao número de espécie de plantas visitadas. Syrphidae foi mais generalista mas, Bombyliidae e Stratiomyidae foram relativamente mais especializadas. Muita espécies de moscas visitam flores, por isso a abundância e frequência de visitas podem indicar sua importância como polinizadores, bem como a importância das flores em sua dieta.

The species of flies that visit flowers to feed were recorded, at the Ecological Station of the Federal University of Minas Gerais (UFMG). Asteraceae, Rhamnaceae, and Boraginaceae were the most visited families. Asteraceae was the richest family and the most visited by flies families and species. The highest diversity of visiting flies was on Baccharis trinervis (Lam.) (H'=1.86). The most diverse families of Diptera were Syrphidae (H'= 2.07) and Bombyliidae (H'= 1.52). The syrphids Ornidia obesa (L.) and Palpada furcata (Wied.) were the most abundant species amongst visitors. Despite the total abundance of Diptera was significantly higher in the rainy season, when a higher number of plants were blooming, there were more families of visitors during the dry season. The number of females in four families of flies was typically slightly higher than the number of males. Calliphoridae and Sarcophagidae showed similar patterns regarding the number of plant species visited, while Syrphidae were the most generalized, and Bombyliidae and Stratiomyidae visited few plant species. Many species of Diptera visit flowers, and their abundance on plants could indicate their importance as pollinators as well the importance of flowers for their diet.