TRANSACTIONS RESEARCH ARTICLE TAES 140: 163-184authors.entomology-aes.org/article/public/11.pdf · TAES 140: 163-184 ISSO 0002-8320 TRANSACTIONS AMERICAN ENTOMOLOGICAL SOCIETY RESEARCH

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TRANSACTIONS AMERICANENTOMOLOGICALSOCIETY

RESEARCH ARTICLE

Publication date:15 May 2014 urn:lsid:zoobank.org:pub:5534B48B-DDD3-40E4-AFD3-859F0CD4F0FF

Two new species of Neoxabea, three new species of Oecanthus, and documentation of two other species in Nicaragua (Orthoptera: Gryllidae: Oecanthinae)

Nancy Collins, Eric van den Berghe and Lisa Carson

[NC] [email protected] [EVDB] [email protected] (University of the Americas, Managua, Nicaragua)[LMC] [email protected] (Dartmouth College, Hanover, NH, USA)

ABSTRACT

Two new species of Neoxabea and three new species of Oecanthus are described from Nicaragua: N. cerrojesusensis and N. ottei, O. belti, and O. symesi occur at higher elevations in the northern half of Nicaragua. A large population of O. bakeri was found in dry tropical forest west of Lake Nicaragua. The presence of O. allardi in Nicaragua is documented as the first record outside of the West Indies, and waveforms from the first known recordings of a singing male O. leptogrammus are provided. Keys are provided for Neoxabea and Oecanthus in Central America.

INTRODUCTIONS

Oecanthinae have been described from the Americas, Europe, Africa, Asia, India, Australia and islands in the Caribbean and Pacific. Eades et al. 2013 lists 11 species in the genus Neoxabea and 65 species in the genus Oecanthus. All 11 of the Neoxabea species (Table 1) and 23 of the Oecanthus species (Table 2) occur in the Western Hemisphere south of the United States. Only five species have been previously documented in Central America: N. bipunctata, O. comma, O. leptogrammus, O. prolatus and O. varicornis (Walker 1967).

Collections by EV and NC from ten sites in Nicaragua (Fig. 1) yielded two unknown species of Neoxabea and three unknown species of Oecanthus. The principal collection sites are Cerro Jesus (cloud forest) and Domitila Reserva Silvestre Privada (tropical dry forest). Cerro Jesus (peak elevation 1,792 m), is northwest of Jalapa, Nicaragua, and straddles the northern border with Honduras. The top 600 m is covered in dense virgin cloud forest on the Nicaraguan side, but is clear-cut on the Honduran side. The lower slopes on the Nicaraguan side are cultivated with shade coffee and corridors

of forest along waterways, transitioning to cloud forest around 1,100 m. Domitila Reserva Silvestre Privada (DRSP) is located 46 km southeast of San Marcos, Nicaragua. The property extends to the western shore of Lake Nicaragua (Lago Cocibolca).

Other sites where Oecanthines were encountered or collected include: Cerro Tisey, Datanli Diablo, Jinotega, Kahka Creek, Kilambé, Montelimar, San Marcos and Tepesomoto.

MATERIALS AND METHODS

Genus verification.—There are nine genera of Oecanthinae worldwide, but only two occur in the New World – Oecanthus and Neoxabea. Tree crickets encountered in Nicaragua were identified to genus with a key from Walker (1967). Two of the new species were identified as members of the genus Neoxabea due to the lack of spines on the hind tibiae, and the presence of a tubercle on the distal border of the scape (Figs. 4 & 12). Three of the new species were identified as members of the genus Oecanthus due to the presence of spines on the hind tibiae (Figs. 20, 26, 34 & 58).

NEOXABEA AND OECANTHUS OF NICARAGUA164

Collection methods, sites and dates.—Areas inhabited by Oecanthines at DRSP and Montelimar were determined by locating actively singing males; tree crickets were collected by hand or with sweep nets. Oecanthines at other collection sites were drawn to sheets set up in conjunction with 120-175 watt mercury vapor bulbs, and BioQuip model 2807A 15 watt blacklight tubes. The collection dates for all species ranged from April 2006 to June 2013. Dates for Cerro Jesus were 28-29 April 2006, 1-6 June 2011, 17-20 May 2012, and 6-11 June 2013. Other collection dates are: Cerro Tisey ca 25 April 2011; Datanli Diablo ca 17-21 May 2011; DRSP 2-7 January 2010 and 20-25 January 2011; Jinotega July 2013; Kahka Creek 5-11 May 2011; Kilambé 22-25 May 2011; Montelimar 2-7 January 2010 and 20-25 January 2011; San Marcos 15 March 2011 and 6-11 June 2013; and Tepesomoto April 2011.

Specimens relevant to this study were examined in the entomological collections at the Museo Entomologico in Leon, Nicaragua, and at Ave Maria University, San Marcos, Nicaragua. None were identified beyond genus.

Documentation and preservation of specimen.— Males and females were collected and photographed; singing males were video recorded with sound. Measurements and visual observations for morphological study were made after the specimens were euthanized using acetone. Specimens were preserved in alcohol or dried using anhydrous calcium sulfate crystals. Some specimens had their forewings removed in order to photograph the metanotal gland and to count the teeth on the stridulatory file.

Depositories.—Academy of Natural Sciences of Philadelphia (ANSP); Bernice Pauahi Bishop Museum (BPBM); California Academy of Sciences (CAS); Florida State Collection of Arthropods (FSCA); Museo Entomologico, Leon (MEL); and University of Wisconsin-Madison (UW-Mad). Photographs, audio files and videos of all seven species discussed in this paper will be made available as supplementary material for viewing at www.oecanthinae.com and http://orthoptera.speciesfile.org.

Morphological measurements.—The total length refers to the midline length from the fastigium to the apex of the subgenital plate--not

including antennae, tegmina, limbs or cerci. The tegminal width (at the widest portion) and the length to width ratio (l/w) were measured with the tegmina resting together atop the abdomen. Femur length was measured from the proximal to distal ends of the femur.

Number of teeth on the stridulatory file.—The right tegmen was mounted on a slide and viewed using a First Lab microscope with a 10X digital eyepiece through a 10X power objective lens in order to count the stridulatory file teeth.

Metanotal glands.—The metanotal glands of male specimens can be an important taxonomic character for tree crickets (Walker TJ and Gurney AB 1967). Since not all species have been catalogued by metanotal gland appearance, they are not yet a reliable diagnostic tool. This paper provides photographs for documentation and comparisons (Figs. 48-56). Photographs were taken using a Canon Powershot S5IS though a First Lab microscope with a 10X digital eyepiece through a 4X power objective lens.

Tibial armature.— Subapical, dorsal, hind tibial spines on Oecanthus specimens were examined using a First Lab microscope with a 10X digital eyepiece through a 4X power objective lens.

Song and temperature recordings.—Songs were recorded using a Canon PowerShot S5 IS digital camera set in video mode at 30 frames/sec, with the camera held as close to the singing tree cricket as possible. An avi-to-wav converter marketed online by 008soft.com was used to extract the sound track from the video file. AVS4YOU Audio Editor Software versions 4.2 and 6.1 were used to analyze the sound tracks and to make images of their waveforms. The temperatures within 15 cm of actively singing males were recorded using a hand-held digital thermometer attached to a 3-meter wire cord manufactured by LaCrosse Technology. Accuracy of the digital thermometer was confirmed by comparing, in a water bath, its readings with a precision glass laboratory thermometer.

The pulse rate is documented as pulses per second (p/s), and is calculated during periods of continuous pulse production. It should be noted that the tree crickets presented in this paper sang only at night. Recordings were made during limited visits to Nicaragua since import permits of live specimens

165NANCY COLLINS ET. AL.

into the U.S. for longer observations could not be obtained. Due to consistent night temperatures while in locations visited in Nicaragua, the recordings of singing males were made within an extremely narrow range of temperatures; therefore, no graphs of pulses per second over ranges of temperatures are possible.

Molecular Analysis.—Specimens were sequenced at the 12S locus using primers and conditions from Robillard and Desutter-Grandcolas (2006).

RESULTS

Neoxabea cerrojesusensis n. sp. Collins & van den Bergheurn:lsid:zoobank.org:act:A9A7771B-EB7B-4557-931B-D2C273671C04

Neoxabea cerrojesusensis (Figs. 2 & 3) is currently known only from northern Nicaragua.

Etymology.— Named for the mountain where this new species was discovered.

Habitat.—Drawn to lights; host plants/trees unknown.

Holotype.—Male. Cerro Jesus, in northern Nicaragua. GPS – 13° 59’ N; 86° 11’ W, elevation 1,100m. 6 Jun 2013. E. van den Berghe, collr; deposited at ANSP. Body length 15.5 mm; femur length 7.5 mm; pronotal length 3.0 mm; tegminal length 11.0 mm; tegminal width 4.0 mm. Antennal tubercles as in Fig. 4. Head color brown; pronotum tan; tegmina translucent tan; limbs translucent yellow. Cerci curve inward proximally then outward and end with a pointed tip (Fig. 5). Eight pale ovoid knobs on the dorsal abdomen - one knob per tergum (Fig. 6). Tegmina of the males have a faint X pattern when at rest on the abdomen (Figs. 2 & 18). Stridulatory teeth total 23. Metanotal gland at figure 48.

Female allotype description.—Collected at Cerro Jesus. Body length 15.0 mm; pronotal length 2.9 mm; ovipositor length 4.8 mm; femur length 7.0 mm. Antennal tubercles same as in male. Head color mahogany; pronotum light brown, lighter abdominal region; limbs translucent yellow. Forewings display two dark maculae with whitish

areas (Figs. 3 & 18). Specimen deposited at ANSP.Song diagnosis - The calling song of males

consists of intermittent bursts of rapid trilling. This species starts out with staccato-like clicking sound for 5-25 seconds, then has 0.9-1.3 seconds of a continuous trill with ascending volume. No set patterns of silence, staccato or trilling were identified. Pulse production rate 90 pulses per second (Figs. 7, 8 & 9) and a dominant frequency of 2.7 kHz at 26.1 C.

Molecular analysis - The aligned and trimmed 12S of sequences of N. cerrojesusensis [Genbank Accession Number (GAN): KJ024364] were 278 base pairs.

Paratypes: one male and one female (Cerro Jesus, Jun 2013) to: MEL and UW-Mad; one male and one female (Cerro Jesus, Apr 2006) to: BPBM, CAS and FSCA.

Neoxabea ottei n. sp. Collins & van den Bergheurn:lsid:zoobank.org:act:C8CCE77F-C462-45B8-B0AB-BD7F4DC72720

Neoxabea ottei (Figs. 10 & 11) is currently known only from northern Nicaragua.

Etymology.—Named in honor of Dr. Daniel Otte who has described over 60 species of tree crickets, and is founder of the Orthoptera Species File (an online orthoptera database).

Habitat .—Drawn to lights; host plants/trees unknown.

Holotype.—Male. Cerro Jesus, in northern Nicaragua. GPS 13° 59’ N; 86° 11’ W, elevation 1,100m. 6 Jun 2013. N. Collins, collr; deposited at ANSP. Body length 19.5 mm; femur length 8.5 mm; pronotal length 3.0 mm; tegminal length 11.5 mm; tegminal width 5.0 mm. Antennal tubercles as in figure 12. Head color brown; pronotum tan; tegmina translucent beige; limbs translucent yellow. Cerci curve inward proximally then outward and end with a pointed tip (Fig. 13). Eight pale ovoid knobs on the dorsal abdomen - one knob per tergum which are noticeable through the wings at rest (Figs. 14 & 18). Tegmina of the males have dark markings which form an X pattern of varying clarity when resting on the abdomen. Stridulatory teeth total 20. Metanotal gland photo at figure 49.


Female allotype description – Also located at Cerro Jesus. Length 18.0 mm; ovipositor 5.0 mm. Antennal tubercles same as in male. Medium brown but lighter on the lateral abdominal regions; head and pronotum mahogany. Forewings display four dark maculae – located dorsally (Fig. 11). Specimen deposited at ANSP.

Song diagnosis - The calling song of males consists of intermittent bursts of rapid trilling. This species starts out with a staccato-like clicking sound for up to 25 seconds, then has 0.9-1.3 seconds of a continuous trill with ascending volume. Pulse production rate 94 pulses per second (Figs. 15, 16 & 17) and a dominant frequency of 2.8 kHz at 26.2 C.

Molecular analysis - The aligned and trimmed 12S of sequences of N. ottei [GAN: KJ024365] were 278 base pairs.

Paratypes: one male and one female (Cerro Jesus, Jun 2013) to MEL and UW-Mad; one male and one female (Cerro Jesus, Apr 2006) to BPBM, CAS and FSCA.

Oecanthus bakeri n. sp. Collins & van den Bergheurn:lsid:zoobank.org:act:37032B94-CDA7-444D-B444-DC21535C5549

Oecanthus bakeri (Figs. 19 & 20) is currently known only from Nicaragua.

Etymology.—Named in honor of Charles Fuller Baker for his contribution to the study of Oecanthinae in Nicaragua. Baker described O. rileyi in 1905. He also described O. marcosensis which was collected near San Marcos, Nicaragua. Further analysis led to listing it as a synonym of O. varicornis.

Habitat.— Individuals were readily located at DRSP in the month of January on dense patches of Acanthaceae and Verbena sp. next to a rarely traveled dirt road between wire-fenced pastureland and dry tropical forest. One specimen also collected at lights on Cerro Tisey in 2012.

Holotype.—Male. Nicaragua, Domitila Reserva Silvestre Privada - dry tropical forest in southwestern Nicaragua. GPS – 11° 48’ N 86° 31’ W, elevation 9m. 22 Jan 2011. N. J. Collins, collector. Deposited at ANSP. Body length 16.8 mm; tegminal length 12.0 mm; tegminal width 6.0

mm with wings at rest atop abdomen. Tegmina have scattered darkened areas along veins (Fig. 19). Stridulatory teeth total 25. Dark brown ventral markings (Fig. 21) in whitish fields on the straw-colored scape and pedicel. Color uniformly pale green, lighter in the abdominal region. Pale orange-tan head. Limbs translucent milky green color. Femoral-tibial joints dark orange with a prominent black half-circle. Three rows of light black slash markings down the length of the femur. Front tibial joints deep golden yellow. Cerci straight and slender. Metanotal gland as at figure 52.

Female allotype description.— Collected at DRSP. Overall yellowish-green color. Head has same orange-tan head and black slash markings on the hind femurs as on the male (Fig. 20). Antennal markings same as on male. Deposited at ANSP.

Immature description.—Fifth stage male same in color as adults with same black slashes on hind femurs. Developing wings have black slash markings. Younger instars: dorsal abdomen light green with two longitudinal whitish lines bordering a central strip of reddish-brown, with rows of paired dark grey circles

Song diagnosis.— The calling song of males consists of a rapid trilling - which occurs continuously or as intermittent bursts of trilling of various lengths (Figs. 23 & 24). Recordings were made of DRSP individuals in the field and as captives in containers made of netting, with temperatures ranging from 25.6 C to 27.1 C. Pulse rate at 25.7 C is 80 pulses per second with a dominant frequency of 3.0 kHz.

Tibial armature .—Four large spines in pairs on the distal hind tibiae, with two to four small spines between the large spines – all aligned in two rows (lateral and medial edges). Small spines continue proximally but do not extend into the femur. Spines pale with black tips.

Paratypes.—one male each (DRSP, Jan 2011) to MEL, UW-Mad, and FSCA.


Oecanthus belti n. sp. Collins & van den Bergheurn:lsid:zoobank.org:act:76B568CB-5D91-4D52-9BF6-C331F9303792

Oecanthus belti (Figs. 25 & 26) is currently known only from northern Nicaragua.

Etymology.—Named after Thomas Belt, an amateur naturalist who traveled throughout Nicaragua while doing engineering work 1868-1872. Belt’s book, The Naturalist in Nicaragua, includes many passages about Nicaraguan insects.

Habitat .— Drawn to lights. One female found on Asteraceae: Dahlia dallium (Fig. 26) in a landscaped garden at a coffee farm on Cerro Jesus (elevation 1,100m).

Holotype.—Male. Collected at Cerro Jesus, in northern Nicaragua. GPS 13° 59’ N; 86° 11’ W, elevation 1,100m. 6 Jun 2013. N. Collins, collr; deposited at ANSP. Body length 15.5 mm; femur length 9.0 mm; pronotal length 2.5 mm; tegminal length 12.0 mm; tegminal width 5.0 mm. Antennal markings as in figure 27. Head color pale green and cream; antennae black; scape red and pedicel blackish red; pronotum pale green bordered with white; tegmina translucent green; limbs translucent pale green with orange femoral-tibial joints. Stridulatory teeth total 32. Metanotal gland at figure 53.

Female allotype description.—Collected at Cerro Jesus 6 Jun 2013. Length 16.0 mm; ovipositor 5.0 mm. Pale green body, limbs and pronotum. Rich red on head. Antennae black. Appearance similar to that of female O. varicornis. Specimen deposited at ANSP.

Song diagnosis .—The calling song of males consists of a rapid trilling (Figs. 28 & 29). Pulse rate at 26.7 C. is 81 pulses per second with a dominant frequency of 4.2 kHz.

Tibial armature.—Four large spines in pairs on the distal hind tibiae, with two to four small spines between the large spines – all aligned in two rows (lateral and medial edges). Small spines continue proximally but do not extend into the femur. Spines pale with black tips.

Paratype.—Females to: MEL, UW-Mad, CAS and FSCA.

Oecanthus symesi n. sp. Collins & van den Bergheurn:lsid:zoobank.org:act:89B0CCE8-C2E5-40AD-AF15-1796F0C322A9

Oecanthus symesi (Figs. 30 & 31) is currently known only from Cerro Jesus, Nicaragua.

Etymology.—Named in honor of Dr. Laurel Symes. Dr. Symes earned her PhD using Oecanthinae as her research study group, and verified distinct species status for the two newly described Nicaraguan Neoxabea tree crickets using DNA sequencing with LC.

Habitat .—One female individual was collected via net approximately 15 feet high from a Guava tree aka “Guava roja” (Psidium guajava).

Holotype.— Male. Collected at Cerro Jesus, in northern Nicaragua. GPS 13° 59’ N; 86° 11’ W, elevation 1,100m. 6 Jun 2013. E. Van den Berghe, collr; deposited at ANSP. Body length 16.5 mm; femur length 10.0 mm; pronotal length 2.5 mm; tegminal length 11.5 mm; tegminal width 3.5 mm. Single deep brown vertical lines on first two antennal segments as in figure 32. Color uniformly rich golden yellow with pale yellow limbs and deep orange head and orange pronotum. Cerci slender and pale with dark pointed distal tips (Fig. 33). Mouth palps orange with white distal tips. Front tibial and femoral-tibial joints brownish-orange. Stridulatory teeth total 18. Metanotal gland at figure 54.

Female allotype description.—Collected at Cerro Jesus 6 Jun 2013. Body length 15.5 mm. Ovipositor length 4.5 mm. Antennal markings and overall color same as in male. Specimen deposited at ANSP.

Song diagnosis.—The song pattern matches those of U.S. species in the niveus group - intermittent bursts of trilling (Figs. 35 & 36). Pulse rate at 22.7 C is 58 pulses per second with a dominant frequency of 2.0 kHz. It is noteworthy that while four different species were singing from inside separate net containers, including N. cerrojesusensis, N. ottei, O. belti and O. symesi, the male O. symesi was noticeably lower in volume to the human ear than the other three species, presumably due its narrow tegmina. Given the large number of singing insects on Cerro Jesus, and


the collective volume of their songs, it would be difficult to locate O. symesi calling high in trees.

Tibial armature .—Total of five to six large spines on the distal end of the hind tibia, not situated as pairs, with zero to three small spines between – all aligned in two rows (lateral and medial). Small spines continue proximally but do not extend into the femur. Large spines pale yellow large spines transitioning to orange and then black tips; small spines orange with black tips (Fig. 34).

Molecular analysis.—The aligned and trimmed 12S sequence of Oecanthus symesi [GAN: KJ024362] was 433 base pairs.

Paratypes.—One male (Cerro Jesus, Jun 2013) to CAS; one female (Cerro Jesus, Apr 2006) to MEL and one female UWM (Cerro Jesus, Jun 2013).

Documentation of other Oecanthus species in Nicaragua

Oecanthus allardi Walker TJ & Gurney AB 1960. Identification based on color, size, antennal markings and sound recordings compared to those posted online at Macaulay Library. Photographs and song waveforms (Figs. 37-41) are offered for documentation of this species outside of the West Indies. Metanotal gland at figure 55. Dominant frequency 3.0 kHz at 27.2 C. Collected at Montelimar, DRSP, Kilambé and Cerro Jesus. Male and female specimens deposited at UW-Madison.

Oecanthus leptogrammus Walker TJ 1962. Identification based on color, size, long slender hind femurs, and antennal markings. Photographs and song waveforms (Figs. 42-47) are offered for documentation of this species. Metanotal gland at figure 56. Dominant frequency 2.0 kHz at 27.3 C. Sound recording can be heard at supporting material. Collected at Cerro Jesus. This species was also found at San Marcos, and a female was collected at DRSP. The singing male in the recording and one female from Cerro Jesus deposited at UW-Mad.

DISCUSSION

New species status was determined by comparing morphological characteristics, locations and song patterns to those of species documented in Central America. Special attention was also given to species with similar stridulatory teeth count totals, regardless of location, as presented in Walker TJ (1962) and Walker TJ (1967). Metanotal gland features were compared to those in Walker TJ, Gurney AB (1967) and Walker TJ (1967). Walker’s papers can be accessed at: http://entomology.ifas.ufl.edu/walker/buzz/s576a.htm.

Molecular analysis.—DNA analysis was used to confirm divergence between the new Neoxabea species. The 5.0% divergence between N. cerrojesusensis and N. ottei is comparable to the divergence between each of these species and the North American species, N. bipunctata [GAN: KJ024363]. There is 5.8% divergence between N. bipunctata and N. cerrojesusensis; and 4.3% divergence between N. bipunctata and N. ottei.

DNA analysis of O. symesi revealed 8.7% divergence and two deletions relative to the most similar North American species O. pini [GAN: KJ024361]. However, while it is clear that the sequence from O. symesi is distinct from that of O. pini, caution should be exercised before inferring that O. symesi is much more closely related to O. pini than to other North American species in the nigricornis species group, given the high levels of shared polymorphism and low sequence divergence observed among O. pini and several other members of the nigricornis species group.

Neoxabea cerrojesusensis and N. ottei - Although males of the two new Neoxabea species are very similar in appearance, there are slight differences in the tegminal width. N. cerrojesusensis males have slightly narrower wings with distal ends that appear to blend in with the hindwings; while N. ottei have slightly wider wings with broader distal ends (Fig. 18). Visual differences are more evident in the females of both species. N. cerrojesusensis has an overall darker color than N. ottei, and has two prominent dark maculae compared to four for N. ottei (Fig. 18).

The two new Neoxabea species were also ruled out as being three other species with stridulatory


teeth counts closest down the list on Table 1 by using characters presented in Walker TJ (1967). The distal tip of the cerci of N. astales and N. quadrula are club-shaped; and N. femorata has no knobs on the tergites.

Oecanthus bakeri, O. belti and O. symesi - Out of an abundance of caution, comparisons were made to species documented in Mexico: O. argentinus, O. celerinictus, O. quadripunctatus, O. exclamationis and O. alexanderi. These five species are green with tegminal widths greater than 4.0 mm and thus do not match O. symesi. None match O. bakeri or O. belti as all five lack red on the pedicel or scape. Other non-matching factors are that O. exclamationis has distinctly different antennal markings (upside down exclamation mark) and O. alexanderi chirps rather than trills.

Oecanthus bakeri.—Although the stridulatory teeth total for O. immaculatus is 24 and the total for O. bakeri is 25, O. immaculatus has no antennal markings and is documented only in Peru. Overall colors and antennal markings appear quite different between O. bakeri and O. varicornis. While O. bakeri has dark brown ventral markings in whitish fields on a straw-colored scape and pedicel, O. varicornis has black markings on a red scape and pedicel., The stridulatory teeth total and song pulse rate are similar to O. varicornis, and DNA sequences of O. bakeri showed minimal divergence from O. varicornis; therefore, questions initially existed whether this was a pallid form of O. varicornis. Determination of new species status, however, was made due to differences in the appearance of the tegmina (Fig. 22) and of the metanotal gland. The tegmen of O. varicornis has an overall rounder shape than that of O. bakeri. The l/w ratio of the tegmina at rest: O. varicornis from Texas = 1.8 and O. bakeri = 2. Differences in the metanotal glands can be viewed at figures 51 & 52. Arrows point to rounded lateral borders of the scutum for O. varicornis, and scalloped lateral borders for O. bakeri.

It is interesting to note that in 1905, CF Baker described O. marcosensis, a tree cricket with similarities to O. bakeri found at DRSP. Baker described O. marcosensis from a site near San Marcos, Nicaragua. San Marcos is approximately

30km NE of DRSP. Baker’s description (Baker 1905) included:

Length 18mm. Color a faded brownish, darker on the posterior legs. The antennae are stout, the two basal joints brownish, and each with a slender, longitudinal, dark brown dash beneath; the flagellum is straw colored and with short white pubescence. The tegmina are 14mm long by 5.5mm wide at the widest place; on the reflexed portion are fourteen oblique veins. The wings reach to the tips of the tegmina. The cerci are rather stout, extending to the wing tips, and covered with rather long white hairs of varying lengths. The hind femora have three longitudinal series of short, oblique, straight brown dashes on the outer side, while both femurs and tibiae are sprinkled with minute brown dots; the tibiae bear five pairs of large spines besides the numerous small teeth; the apex of hind tibiae and the hind tarsi are thickly covered with a short golden pubescence.

Further analysis led to listing O. marcosensis as a synonym of O. varicornis. The type specimen is deposited at the National Museum of Natural History (NMNH), but is in a damaged state and is missing its head and thorax. Walker TJ indicated in his 1962 paper that the possibility existed for O. marcosensis to be a species “similar to but distinct from O. varicornis.”

Since the type specimen cannot be utilized for an accurate comparison to the specimens found in Nicaragua for this paper, it seemed more reasonable to name a new species after Baker than to try to prove they are what Baker described as O. marcosensis.

DNA was not analyzed for O. belti; therefore other characteristics were compared.

Oecanthus belti.—The stridulatory teeth total of O. belti is close to that of O. varicornis, O. pallidus and O. major. With the tegmina closed and at rest, the wings of O. belti present as oval-shaped; while the wings of O. varicornis are pear-shaped. These wing differences can be viewed at figures 25 and 57.

The red coloring on the head and black antennae of O. belti is distinctly different from the yellow on the head and pale antennae of O. pallidus. The wings of O. pallidus are also somewhat pear-


shaped (Zefa et al. 2012). O. pallidus is known only from Brazil.

The tegminal width for O. major is 7.2mm (Walker TJ 1967). O. major is known only from Mexico.

Oecanthus symesi.—The narrow tegmina, overall light golden yellow color and orange head of O. symesi, along with the low number of stridulatory file teeth, indicate it is distinctly different from other known Oecanthus species.

Tibial armature – Tibial armature for Oecanthus species is comprised of large and small spines in two rows on the dorsum of the distal hind tibia. One row is on the lateral edge and one row is on the medial edge. The large spines are located distally, with varying numbers of small spines between them. The small spines continue proximally but do not extend into the femur. The large spines on some species are situated as opposing pairs (one in the lateral row and one in the medial row); while the large spines on other species are alternating in position or have no relation to those on the other row. Since the numbers and positions of spines for O. symesi were different from O. bakeri and O. belti, spines were examined on seven additional species of Oecanthus for comparison using a First Lab microscope with a 10X digital eyepiece through a 4X power objective lens. Large spines were situated as matching pairs, and there were generally three or four smaller spines between the large spines for: O. bakeri, O. belti, O. leptogrammus, O. quadripunctatus and O. varicornis. The large spines were not situated as matched pairs, and there were zero to four small spines between same-row pairs of large ones for: O. forbesi, O. fultoni, O. niveus, O. pini and O. symesi.

Keys to Oecanthinae in Central America

The following keys summarize characters which are useful in identifying specimens or live tree crickets in Central America. Oecanthus specimens do not retain colors as well as Neoxabea, but the antennal markings can generally be seen on discolored specimens. These keys include five new species from Nicaragua and other tree crickets documented in Central America, using characters from Walker TJ, Gurney AB 1960, Walker TJ 1962, and Walker TJ 1967.

Key to Genera

1 Hind tibiae smooth with no spines (have terminal spurs only); prominent tubercle on the first antennal segment . . . . . . .Neoxabea

1’ Distal hind tibiae with spines; no prominent tubercle on the first antennal segment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Oecanthus

Key to Neoxabea Species in Central America

1 Males . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21’ Females . . . . . . . . . . . . . . . . . . . . . . . . . . 5

2(1) Stridulatory teeth count 30 or less . . . . . . 32’ Stridulatory teeth count greater than 30 . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . formosa

3(2) Setae or brushes prominently visible within metanotal orifice . . . . . . . . . . . . . . . . . . . . 4

3’ Sparse or no visible setae within metanotal orifice . . . . . . . . . . . . . . . . . . . . . bipunctata

4(3) Tegmina do not extend beyond lateral sides of abdomen . . . . . . . . . . . . . cerrojesusensis

4’ Tegmina extend slightly past sides of abdo-men . . . . . . . . . . . . . . . . . . . . . . . . . . . . ottei

5(1’) Dark brown with two prominent blackish maculae . . . . . . . . . . . . . . . cerrojesusensis

5’ Medium brown with four prominent blackish maculae . . . . . . . . . . . . . . . . . . . . . . . . ottei


Key to Oecanthus species in Central America

1 Predominantly green in color; tegminal width 4.1mm or more . . . . . . . . . . . . . . . . 2

1’ Golden yellow color with dark orange head and pronotum; tegminal width 4.0mm or less . . . . . . . . . . . . . . . . . . . . . . . . . . . . . symesi

2(1) Markings on pedicel and scape not of same configuration . . . . . . . . . . . . . . . . . . . . . . 3

2 Markings on pedicel and scape have same configuration; or only scape mark visible . 4

3(2) Mark on scape round or comma-shaped, mark on pedicel straight . . . . . . . . . comma

3’ Mark on pedicel round, mark on scape straight . . . . . . . . . . . . . . . . . . . . . . prolatus

4(2) Markings on scape and pedicel are not round dots . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

4’(2’) Round black dot in white field on both pedi-cel and scape; male song consists of trilled chirps . . . . . . . . . . . . . . . . . . . . . . . . allardi

5(4). Both marks on pedicel and scape are readily visible; antennal markings are vertical lines on white fields; antennae pale; scape pale or straw-colored; pedicel same intensity or lighter than scape . . . . . . . . . . . . . . . . . . . . 6

5’. Only scape mark readily visible; scape mark is black vertical line not on white field; an-tennae black; scape dark red; pedicel darker than scape . . . . . . . . . . . . . . . . . . . . . . . . . 7

6(5) Medium width line on pedicel and scape; head predominantly pale orange;

male song continuous trilling; dark slash marks on hind femurs . . . . . . . . . . . . bakeri

6’ Very thin line on pedicel and scape; patch of medium orange on head; male song intermit-tent bursts of trilling; hind femurs without dark slash markings . . . . . . leptogrammus

7(5’) Tegminal width at rest atop abdomen 5.0mm or less; tegmen at rest have long oval appear-ance . . . . . . . . . . . . . . . . . . . . . . . . . . . belti

7’ Tegminal width at rest atop abdomen 5.7mm or greater; tegmen at rest have pear-shaped appearance . . . . . . . . . . . . . . . . . varicornis

Nicaragua lacks an in depth study of Orthoptera; therefore, the potential exists for additional sites for Oecanthinae, as well as discovery of more new species. In order to further understanding of Oecanthinae in Nicaragua, investigation of host plants, and song recordings / analysis at a wider range of temperatures for all species in Nicaragua are needed. As DNA sequencing capabilities broaden, analysis of O. allardi from Nicaragua compared to O. allardi from the West Indies would be of interest. Additionally, advanced DNA analysis of O. bakeri and O. varicornis would better define their placement on a phylogeny tree. Further study of the tibial armature for all species of Oecanthus would be of interest.

ACKNOWLEDGEMENTS

Initial tree cricket specimens from Cerro Jesus, Cerro Tisey, Datanli Diablo, Kahka Creek and Kilambé are products of LLAMA Leaf Litter Arthropod Survey of Mesoamerica with John T. Longino and Robert S. Anderson as Project Investigators of National Science Foundation Grant # DEB-1157383. We are grateful to Jean Michel Maes for obtaining the necessary export permits, and the Ministerio del Ambiente y los Recursos Naturales Nicaragua (MARENA) for granting the permits. Ricardo Antonio Jarquin Urbina, Wiston Valle Mejia, Dan Heffern and Brian Raber assisted with collection of specimens; Laurel Symes assisted with DNA sequencing; and Nydia Damaris Molina identified the host plant for O. symesi at Cerro Jesus. We are appreciative of invaluable suggestions from Thomas J. Walker and John LaPolla for improving this manuscript. Thomas J. Walker’s 1967 paper examining species found south of the United States was immensely helpful in diagnosing these new Nicaraguan species. We also acknowledge entomological equipment support from IDEAWILD to EV.


Finally, we extend thanks to Bing Kirk and the friendly helpful staff of Cerro Jesus for welcoming the advancement of science, generously leasing facilities to scientists and environmentalists, and above all having the foresight to conserve and protect one of few remaining significant examples of cloud forest in northern Nicaragua.

REFERENCES

Baker CF (1905) Homoptera: On the Gnathodus Species of the Abdominalis Group. Invertebrata Pacifica 1:82.

Eades DC, Otte D, Cigliano MM, Braun H. Orthoptera Species File Online. Version 2.0/4.1. Available from: http://Orthoptera.SpeciesFile.org (accessed October 2013).

Cornell University. Macaulay Library. Available from: http://macaulaylibrary.org/audio/114499 (accessed December 2013).

Robillard T, Desutter-Grandcolas L (2006) Phylogeny of the cricket subfamily Eneopterinae (Orthoptera, Grylloidea, Eneopteridae) based on four molecular loci and morphology. Molecular Phylogenetics and Evolution 40: 643-661.

Walker TJ (1962) The taxonomy and calling songs of United States tree crickets (Orthoptera: Gryllidae: Oecanthinae). I. The genus Neoxabea and the niveus and varicornis groups of the genus Oecanthus. Annals of the Entomological Society of America 55: 303-322.

Walker TJ (1963) The taxonomy and calling songs of United States tree crickets (Orthoptera: Gryllidae: Oecanthinae). II. The nigricornis group of the genus Oecanthus. Annals of the Entomological Society of America 56: 772-789.

Walker TJ (1967) Revision of the Oecanthinae (Orthoptera: Gryllidae) of America South of the United States. Annals of the Entomological Society of America 60: 784-796.

Walker TJ (2013) Singing insects of North America: crickets and katydids. [SINA] http://entnemdept.ifas.ufl.edu/walker/Buzz/ (accessed December 2013)

Walker TJ, Gurney AB (1960) A new species of Oecanthus from the West Indies (Orthoptera, Gryllidae). The Florida Entomologist 43(1): 9-13.

Walker TJ, Gurney AB (1967) The metanotal gland as a taxonomic character in New World Oecanthus (Orthoptera, Gryllidae). Proceedings of the Entomological Society of Washington 69: 157-161.

Zefa E, Schneid Neutzling A, Rutz Redü, D, Lobregat de Oliveira G, Martins L ( 2012) A new species of Oecanthus and Oecanthus lineolatus Saussure, 1897 from Southern Brazil: species description, including phallic sclerites, metanotal glands and calling song (Orthoptera: Gryllidae: Oecanthinae). Zootaxa 3360:55.


Fig. 1. Collection sites in Nicaragua


Figs. 2-9. N. cerrojesusensis. 2. Male. 3. Female. 4. Antennal tubercles or knobs. 5. Cerci. 6. Knobs on dorsal abdominal tergites. 7. 1-sec waveform of staccato prelude (sound like clicks). 8. 1-sec waveform at 26.1 C; 90 p/s. 9. 14-sec waveform at 26.1 C. Staccato-like clicking sounds gradually increase in speed before onset of continuous trill which increases in volume and then ends abruptly. (One trilling period between yellow markers.)


Figs. 10-17. N. ottei. 10. Male. 11. Female. 12. Antennal tubercles or knobs. 13. Cercus. 14. Knobs on dorsal abdominal tergites. 15. 1-sec waveform of staccato warm up transitioning to trilling. 16. 1-sec waveform of continuous trilling at 26.2 C; 94 p/s. 17. 3-sec waveform at 26.2 C.


Fig. 18. Comparisons of color and markings of N. cerrojesusensis (L) and N. ottei (R). Note the width of the tegmina of the N. cerrojesusensis males compared to those of the N. ottei. Also note the N. cerrojesusensis female has two prominent dark maculae on the forewings compared to four on N. ottei.


Figs. 19-24. O. bakeri. 19. Male. 20. Female. 21. Tegmen of O. varicornis from Texas (L) and O. bakeri from DRSP (R). 22. Antennal markings. 23. 1-sec waveform from DRSP at 25.7 C; 80 p/s. 24. 22-sec waveform from DRSP at 25.7 C.


Figs. 25-29. O. belti. 25. Male. 26. Female. 27. Antennal markings. 28. 1-sec waveform at at 26.7 C; 81 p/s. 29. 20-sec waveform at 26.7 C.


Figs. 30-36. O. symesi. 30. Male. 31. Female. 32. Antennal markings. 33. Cerci. 34. Tibial armature. 35. 1-sec waveform at 22.7 C; 58 p/s. 36. 10-sec waveform at 22.7 C.


Figs. 37-41. O. allardi. 37. Male. 38. Immature female. 39. Antennal markings. 40. 1-sec waveform at 27.2 C (one ‘chirp’ consisting of an opening double pulse then 11 trios). 41. 15-sec waveform at 27.2 C.


Figs. 42-47. O. leptogrammus. 42. Male (Note: dark areas on limbs not present prior to exposure to alco-hol.) 43. Female. 44. Antennal markings. 45. 1-sec waveform at 27.3 C; 82 p/s. 46. 5-sec waveform at 27.3 C. 47. 20-sec waveform at 27.3 C.


Figs. 48-56. Metanotal glands: 48. N. cerrojesusensis 49. N. ottei 50. N. bipunctata (from US, for comparison) 51. O. varicornis (from US, for comparison with O. bakeri) 52. O. bakeri 53. O. belti 54. O. symesi 55. O. allardi 56. O. leptogrammus (Note: Some are aged specimens, thus colors are unreliable.)


Fig. 57. Shape of tegmina of male O. varicornis from US, for comparison with tegmina shape of O. bakeri.


Fig. 58. Tibial armature of male O. varicornis from US, for comparison with O. symesi.

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