Research Article |
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Corresponding author: Gustavo Fontecha ( gustavo.fontecha@unah.edu.hn ) Academic editor: Christopher Majka
© 2025 Mauricio Hernández, Mauricio Michel, Joel García, Geisy Dueñas, Marcela Moncada, Kevin Amaya, Yensi Yánez, Alejandra Pinto, Gabriela Matamoros, Alejandro Zamora, Gustavo Fontecha.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Hernández M, Michel M, García J, Dueñas G, Moncada M, Amaya K, Yánez Y, Pinto A, Matamoros G, Zamora A, Fontecha G (2025) Diversity of beetles (Arthropoda, Insecta, Coleoptera) associated with coniferous forests in Honduras. ZooKeys 1226: 101-119. https://doi.org/10.3897/zookeys.1226.136987
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Bark beetles are among the primary drivers of tree mortality in coniferous forests worldwide. Individuals belonging to the order Coleoptera were identified across different forest areas in Honduras. Descriptive statistics were used to calculate the number of families, subfamilies, genera, and species collected per department. Moreover, the barcoding approach was used by amplifying and sequencing the mitochondrial COI gene. The intraspecific genetic diversity of Ips apache was also analyzed. 1,131 individuals were examined and 27 genera were identified. Most of the specimens were identified as belonging to the genus Ips, accounting for 53.2% of the total. Xyleborus accounted for 16.5% and Temnoscheila accounted for 10%. Fewer than four individuals were found for fifteen genera. 68% of the specimens were identified to the species level, and all the specimens were identified to the genus level. Ips, Temnoscheila, Xyleborus, Hypothenemus, and Pityophthorus exhibited the most extensive geographic distribution among the sampled sites. At the genus level, Olancho, El Paraíso, and Copán displayed the highest diversity. This study also marks the first report of the genera Xylomeira and Stephanopachys in Honduran pine forests. Within I. apache, evidence of intraspecific genetic diversity was observed, although no population structure was detected. While this research provides an updated inventory of beetle species associated with Honduran coniferous forests, further taxonomic surveys and ecological studies are essential to better understand the spread and impact of bark beetles in pine ecosystems.
Ambrosia beetles, bark beetles, Coleoptera, Honduras, Ips apache, pine forests
In the last decades, the faunistic composition of forest ecosystems has experienced significant changes because of bark beetle attacks (
Several bark beetle species have been the subject of research in Central America, particularly those in the genus Dendroctonus due to their aggressive behavior in invading and destroying pine forests (
In North and Central America, Wood´s monograph (
During 2018–2023 a total of 1,131 insects of the order Coleoptera were collected from 12 departments of Honduras (e.g., Comayagua, Copán, Cortés, El Paraíso, Francisco Morazán, Intibucá, La Paz, Lempira, Olancho, Santa Bárbara, Yoro, and Atlántida) (Fig.
To magnify morphological features, specimens were observed under stereomicroscopes (Zeiss Stemi DV4 and UNITRON Z10 series) and identified using dichotomous keys (
The species were classified based on the feeding habits of their immature stages, as documented in the literature for each species: (a) myelophages or with feeding in the medulla; (b) phyllophagous to those that feed in the inner cortex; (c) feeding of the roots; (d) spermatophagous or seed feeding; (e) xylomycetophagous or fungal growers, and (f) xylophages to those that feed on xylem tissues. In a simplified way, all the genera that feed on phloem tissues were considered bark beetles, and those that cultivate fungi were considered ambrosial. Those that feed on tissues outside the trunk (such as seeds or roots) or internal tissues such as the pith were not considered.
Statistical analyses were performed using the R software v. 4.3.2 (
After morphological identification, individuals were stored separately in 1.5 mL tubes with 70% ethanol. Then, a small portion of soft tissue was retrieved from the abdomen for DNA barcoding analysis. A subset of 351 samples (31%) were molecularly evaluated. Those genera with less than three individuals were not sequenced since specimens were fully preserved to corroborate their identification and as vouchers. Detailed information about the sequenced samples can be found in the Suppl. material
Genomic DNA was isolated using the Extracta DNA Prep for PCR kit® (QuantaBio, Beverly, MA, USA) following the manufacturer’s instructions. Briefly, soft tissues were macerated and incubated at 95 °C in 100 μL of extraction reagent for 25 minutes and then cooled to room temperature for 5 minutes. Then, 100 μL of stabilization buffer was added and the final volume (200 μL) was transferred to a new 1.5 mL vial. A fragment of the mitochondrial gene COI was amplified using one of three primer pairs (Table
| Protocol | Primer name | Sequence (5´- 3´) | Reference |
|---|---|---|---|
| A | LCO-1490 | GGT CAA CAA ATC ATA AAG ATA TTG G |
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| HCO-2198 | TAA ACT TCA GGG TGA CCA AAA ATC A | – | |
| B | BC1Fm | GTA AAA ACG ACG GCC AGT TCW AAY CAY AAR GAY ATY GG |
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| HCO-2198 | – | – | |
| C | C1-N-2650 | CCN GTR AAT ARN GGG AAT CAT TG |
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| C1-J-2183 | CAA CAT TTA TTT TGA TTT TTT GG |
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The PCR reactions were conducted in a 50 μL reaction mixture, containing 25 μL of KOD OneTM PCR master Mix (Toyobo Co, Ltd. Tokyo, Japan), 2 µL of each primer (100 µM), 2 µL of acetylated albumin – BSA (10 mg/mL), 15 μL of nuclease-free water, and 4 μL of DNA template. PCR reactions were performed under the following conditions: initial denaturation at 98 °C for 30 s, followed by 37 cycles of 10 s at 98 °C, annealing at 50 °C for 10 s, elongation at 68 °C for 2 min, and a final extension at 68 °C for 2 min. A negative control was included for each set of reactions. The PCR efficiency was then visualized through a 1% agarose gel electrophoresis with ethidium bromide. The resulting PCR products were purified and sequenced by Psomagen® (Rockville, MD, USA) (https://www.psomagen.com).
The raw sequences were edited and assembled using Geneious® prime software (Dotmatics, Boston, MA) (
To analyze the intraspecific genetic diversity of I. apache, 52 assembled sequences were aligned, and the resulting alignments were utilized to create a dendrogram using the Tamura-Nei genetic distance model and the Neighbor-Joining tree construction method and performing 1000 iterations of Bootstrap. A homologous sequence of Enoclerus sp. was included as an outgroup in the analysis. The collecting site was considered to ascertain the presence of a population structure for I. apache.
The number of polymorphisms among the I. apache sequences, the number of segregating sites (S), the average nucleotide differences (k), the number of haplotypes (H), the haplotype diversity (Hd), and the nucleotide diversity (π) were calculated using DnaSP Software (v. 6.12.03) (
This study evaluated the diversity of beetles associated with coniferous woods in Honduras. Using morphological traits, we identified 27 genera of Coleoptera collected in 12 departments of Honduras. The community composition was grouped into four families and nine subfamilies (Table
Identification of Coleoptera specimens at the taxonomic levels of Families, subfamilies, and genera. Mye = Myelophagy; Phl = Phylophagy (feeding on the inner cortex); RF = root feeding; Spm = spermatophagy; Xlm = xylomycetophagy; Xyl = xylophagy; NA = not applicable; ND = not defined.
| N | Family | Subfamily | Genus | Ecological group (Reference) | Category | Number (%) |
|---|---|---|---|---|---|---|
| 1 | Bostrichidae | Dinoderinae | Stephanopachys |
Xyl ( |
NA | 1 (0.09%) |
| 2 | Bostrichinae | Xylomeira |
Xyl ( |
NA | 1 (0.09%) | |
| 3 | Curculionidae | Cossoninae | Tomolips |
ND ( |
NA | 61 (5%) |
| 4 | Stenoscelis |
ND ( |
NA | 2 (0.2%) | ||
| 5 | Entiminae | Mimographus |
RF ( |
NA | 1 (0.09%) | |
| 6 | Platypodinae | Euplatypus |
Xlm ( |
Ambrosia | 35 (3%) | |
| 7 | Tesserocerus |
Xlm ( |
Ambrosia | 1 (0.09%) | ||
| 8 | Scolytinae | Araptus |
Phl, Spm ( |
Bark | 1 (0.09%) | |
| 9 | Cryptocarenus |
Spm ( |
NA | 10 (0.9%) | ||
| 10 | Coccotrypes |
Phl, Spm ( |
Bark | 1 (0.09%) | ||
| 11 | Corthylus |
Xlm ( |
Ambrosia | 2 (0.2%) | ||
| 12 | Dendroctonus |
Phl ( |
Bark | 4 (0.3%) | ||
| 13 | Gnathotrichus |
Xlm ( |
Ambrosia | 22 (2%) | ||
| 14 | Hylastes |
Phl ( |
Bark | 6 (0.5%) | ||
| 15 | Hylocurus |
Phl ( |
Bark | 1 (0.09%) | ||
| 16 | Hypothenemus |
Phl, Spm, Xlm ( |
Bark/Ambrosia | 24 (2%) | ||
| 17 | Ips |
Phl ( |
Bark | 602 (53%) | ||
| 18 | Monarthrum |
Xlm ( |
Ambrosia | 3 (0.3%) | ||
| 19 | Micracis |
Xyl ( |
NA | 1 (0.09%) | ||
| 20 | Pityophthorus | Mye, Phl | Bark | 16 (1.4%) | ||
| 21 | Taurodemus |
Xlm ( |
Ambrosia | 1 (0.09%) | ||
| 22 | Xyleborinus |
Xlm ( |
Ambrosia | 14 (1.2%) | ||
| 23 | Xyleborus |
Xlm ( |
Ambrosia | 187 (16.5%) | ||
| 24 | Cleridae | Clerinae | Enoclerus | Pred ( |
Predator | 21 (1.8%) |
| 25 | Tilinae | Cymatodera | Pred ( |
Predator | 1 (0.09%) | |
| 26 | Trogossitidae | Trogossitinae | Temnoscheila | Pred ( |
Predator | 111 (10%) |
| 27 | Tenebroides | Pred ( |
Predator | 1 (0.09%) | ||
| Total | 1131 (100%) | |||||
In terms of relative abundance, our results revealed that Ips (54%), Xyleborus (16.5%), Temnoscheila (10%), Tomolips (5%), Euplatypus (3%), Hypothenemus (2%), and Gnathotrichus (2%) comprised more than 93% of the total collected individuals, whereas the other 20 genera accounted 7% of the collection. In addition, according to the number of elytral declivity spines, two species of Ips were identified: I. apache and I. cribricollis, most of them collected in Francisco Morazán, Yoro, and Olancho.
The largest number of specimens of Coleoptera were collected in El Paraíso (n = 209; 18.5%), followed by Olancho (n = 186; 16.4%), Yoro (n = 178; 15.7%), Copán (n = 167; 14.8%), Francisco Morazán (n = 121; 10.7%). The remaining departments contributed less than 7% of the total (Fig.
Map of Honduras showing the proportion of genera identified in eleven departments of Honduras. The size of the pie diagrams is proportional to the number of insects identified compared to the total. In the department of Cortés, a single individual of the genus Temnoscheila was identified, which is not shown in the graph. Department codes: CP: Copán; CY: Comayagua; EP: El Paraíso; FM: Francisco Morazán; IN: Intibucá; LP: La Paz; LE: Lempira; OL: Olancho; SB: Santa Bárbara; YO: Yoro.
Diversity of specimens was computed using the Hill numbers by parameterizing the q value. For instance, diversity analysis at order q = 0 revealed that four departments have the greatest richness of genera: Olancho and El Paraíso have effective numbers of 17, Copán = 10, and Francisco Morazán = 9; whereas taxonomic diversity at order q = 1 increased in El Paraíso (n = 6.5), Olancho (n = 5.8), Santa Bárbara (n = 5), La Paz (n = 4.5) and Copán (n = 4.4) (Fig.
DNA was isolated from 376 individuals, and successful amplification was achieved for 212 (56.4%) using at least one of the PCR procedures, from which 124 sequences (55.5%) yielded a high-quality score. A total of 56 sequences were identified as I. apache (44.8%), 21 as I. cribricollis (16.8%), 12 as Xyleborus spp. (10.4%), 6 as Euplatypus spp. (4.8%), and 5 as Temnoscheila spp. (4.0%). Additionally, five sequences were from Gnathotrichus spp. and Hypothenemus spp., and three sequences were from Cryptocarenus lepidus. Moreover, four sequences were from Enoclerus spp., two sequences each from Pityophthorus spp. and Tomolips spp., and one sequence each from Hylastes spp. and Xyleborinus spp. GenBank accession numbers and BOLD identification numbers (BINs) are listed in Suppl. material
Regarding the analysis of intraspecific diversity of I. apache, it was observed that among 51 sequences with a length of up to 630 bp, the number of identical sites was 568 (81.5%), and the Pairwise % identity coefficient was 98.6%. A population structure related to the collection site was not demonstrated for I. apache (Fig.
To analyze the number of haplotypes in the I. apache population, 49 sequences of 527 bp were aligned. The number of segregating sites (S) was 93. The nucleotide diversity (π) was equal to 0.0142, and the average nucleotide difference (k) was 7.156. Twenty-three haplotypes (H) were found (Fig.
To explore the influence of natural selection on population structure, Tajima’s D test was performed on the COI sequences and calculated a D value of –2.45039 (Statistical significance: **, p < 0.02). Fu and Li’s D* and F* tests resulted in values of –5.47644 and –5.19970 respectively (Statistical significance: **, p < 0.02), suggesting an excess of rare variation, consistent with population growth, or positive selection.
Limited research has been conducted on the biodiversity of beetle fauna associated with coniferous forests in Honduras, restricting our understanding of their ecological and functional roles. Therefore, a better understanding of insect inventories and spatial distribution is required to increase awareness of beetle outbreaks and their negative impacts on ecosystem services at regional scales. In this study, we used a combination of morphological and molecular methods to analyze the community composition of bark and ambrosia beetles, along with their natural predators, in pine forests. Overall, our integrative analysis provided a more complete and suitable assessment of the forest insect community at lower taxonomic levels (e.g. genus and species). In line with our findings, recent studies have also evidenced the suitability of integrated morphological and molecular approaches to taxonomic analysis in insect communities (
Our collection revealed a high diversity of beetles, composed of 27 genera, with the majority found in the subfamily Scolytinae (60%). Ips, Temnoscheila, and Xyleborus displayed the broadest range of distribution in Honduras. Recent studies have suggested that these beetles play a crucial role in forest ecosystem dynamics, enabling ecological balance, natural renewal process, forest structure, and succession (
According to the statistical analysis at the genus level, Olancho and El Paraíso harbored the greatest beetle richness (q = 0). However, the relative abundance of common genera (q = 2) increased in El Paraíso compared to Olancho, suggesting a low presence of rare beetles with an increasing number of common genera in the community. It has been mentioned that rare beetle species are more sensitive to environmental changes (
Our findings revealed that the secondary bark beetle species of the genus Ips and their natural enemies, i.e., Temnoscheila (Trogossitidae) and Enoclerus (Cleridae), occur simultaneously in most sampled sites, indicating an overlapping distribution. Both genera have been extensively identified as associated predators of harmful forest pests such as Ips and Dendroctonus species (
DNA barcoding has become a powerful tool for estimating intraspecific genetic diversity in Coleoptera (
On the other hand, the neighbor-joining analysis and the haplotype network show intraspecific genetic differences among individuals of I. apache, however the sequences clustered without any clear structure. Moreover, a π value of 0.0142 suggests a moderate level of genetic diversity whilst a haplotype diversity (Hd) of 0.9073, indicates a high level of genetic variability. A lack of genetic differentiation among populations coupled with moderate to high levels of genetic diversity, may suggest gene flow among individuals inhabiting different coniferous forests in Honduras. In addition, the predominance of two haplotypes implies that certain haplotypes are more common within the population, which could be due to selective advantages or historical demographic events.
Additionally, neutrality tests indicate an excess of rare genetic variation, consistent with either population growth or positive selection. This suggests that I. apache populations are likely well-adapted to the environmental conditions of Honduran coniferous forests, enhancing their persistence and facilitating their spread within these habitats. Ips apache is a well-known species for its host specialization and feeding primarily on pine forests (
As far as we know, this research is one of the first investigations conducted on the diversity of beetles associated with coniferous forests in Honduras. A total of 1,131 individuals were examined, revealing 27 genera, with Ips being the most prevalent, followed by Xyleborus and Temnoscheila. Species-level identification was achieved for 68% of the specimens, while all were identified to the genus level. Ips, Temnoscheila, Xyleborus, Hypothenemus, and Pityophthorus exhibited the broadest geographic distribution across the sampled sites. Olancho, El Paraíso, and Copán demonstrated the greatest genus-level diversity. Additionally, this study presents the first record of the genera Xylomeira and Stephanopachys in Honduran pine forests. Furthermore, the mitochondrial COI gene reveals significant genetic diversity among I. apache populations but no structure, suggesting gene flow among individuals from different localities. Additionally, due to the greater impact of bark beetles in Honduran pine forests, our findings are important for pest management strategies and phytosanitary measures to prevent the risk of introduction and spread of harmful beetle species. Lastly, future studies should focus on understanding the trophic relationships between bark beetles and natural predators, providing valuable insights into fundamental ecological processes in coniferous forests.
We thank Dr. Liu Lan-Yu for corroborating the identification of both Bostrichidae genera and Dr. Andrew Johnson for corroborating the identification of Taurodemus. We also thank María Guadalupe del Río, PhD, and Kevin Cortés Hernández, MSc for corroboration of Mimographus (Curculionidae: Entiminae).
The authors have declared that no competing interests exist.
No ethical statement was reported.
This research was funded by ICF, Red Solidaria, BID, grant number “Proyecto Manejo Sostenible de Bosques (BID 3878/BL-HO)”.
Conceptualization: KA, YY, GF. Data curation: MM, JG, GF, KA, AZ, GD, MH. Formal analysis: JG, MH, GF. Funding acquisition: GF, YY. Investigation: MH, AZ, GF, JG, GD, MM. Methodology: MM, GF, JG. Project administration: GF, GM, AP. Resources: GF. Supervision: GF, AP, GM. Validation: GD. Writing – original draft: GF. Writing – review and editing: GD, AP, JG, MM, GM, MH, AZ, KA, MM, YY.
Mauricio Hernández https://orcid.org/0000-0003-0205-3344
Mauricio Michel https://orcid.org/0009-0009-2331-6810
Joel García https://orcid.org/0000-0002-0574-758X
Marcela Moncada https://orcid.org/0009-0003-2380-1548
Alejandra Pinto https://orcid.org/0000-0003-3890-0218
Gabriela Matamoros https://orcid.org/0000-0003-2177-9765
Gustavo Fontecha https://orcid.org/0000-0001-9756-4520
All of the data that support the findings of this study are available in the main text or Supplementary Information.
Database with the identification of the specimens in the collection
Data type: xlsx
GenBank accession numbers and BOLD BINs for the sequences generated in this study
Data type: xlsx
Photographic catalog of the genera of Coleoptera described in this study
Data type: docx
Explanation note: Species are listed in order of abundance.