Eucynorta rooneyi, Damron & Pinto-Da-Rocha & Longhorn, 2018

Damron, Brittany N., Pinto-Da-Rocha, Ricardo & Longhorn, Stuart J., 2018, Description of a new species of Eucynorta (Opiliones, Cosmetidae) from Cortés, Honduras, Zootaxa 4450 (1), pp. 125-134 : 126-132

Eucynorta rooneyi sp. nov.

( Figs 1–3 , 4C )

Type material. Male holotype ( MZSP 71769 ): Parque Nacional Cusuco , San Pedro Sula, Cortés Department , Honduras, vii–viii.2015, B.N. Damron col. – Paratypes: 1 male, 2 females (MZSP 71770), 1 male, 1 female ( AMNH), same data as the holotype ; 1 male, 1 female ( UNAH), 1 male, 2 females ( OUMNH), 1 male, 1 female ( NHMUK), same locality as holotype, 25.vii.2011, M.V. Lock & S.J. Longhorn col.

Other material examined. HONDURAS. Cortés Department. Parque Nacional Cusuco, San Pedro Sula, vi– viii.2012, B.N. Damron col., 1 male, 1 female ( MZSP 74030 ) ; same locality, vi–viii.2015, B.N. Damron, T.J. Creedy col., 4 males, 1 female ( MZSP 74031 ) ; same locality, vii.2011, S.J. Longhorn, M.V. Lock, K.O. Sagastume, T.J. Creedy col., 3 males, 11 females ( OUMNH) . 2 males, 4 females (UNAH).

Type locality. Parque Nacional Cusuco , Municipio San Pedro Sula, Departamento Cortés , Honduras.

Distribution. Currently this species is only known from Parque Nacional Cusuco in the Sierra del Merendón, Honduras. Core zone of the park is at 1800–2242 m asl. (15°29.8'N ¯ 15°32.1'N, 88°13.0'W ¯ 88°16.3'W).

Etymology. The specific name is a tribute to Dr. Thomas P. Rooney, Master’s thesis advisor to Brittany Damron. Dr. Rooney went above and beyond providing encouragement and support to a beginner scientist.

Diagnosis. Eucynorta rooneyi sp. nov. has two spines on area III, six tarsi on leg I, with three basitarsi swollen in males, roughly granulate cheliceral bulla and relatively long, gracile straight posterior legs of similar thickness to anterior legs. E. rooneyi sp. nov. is overall reddish-brown with distinctive yellow markings on the prosoma and areas I and IV of the DS ( Fig. 1A ; 4C ). More distinctly, E. rooneyi sp. nov. has free tergites that lack granulation, and males bear granules on the ventral surface of femur III as well as more conspicuous armature on the ventral surface of femur IV.

Comparisons. E. rooneyi sp. nov. is similar to the type species of Eucynorta , E. quadripustulata from Colombia (and supposedly Panama: Petrunkevitch 1925), in having all the defining Roewerian characters; spines on area III of DS, six tarsi on leg I three basitarsi swollen in males (the latter only implied for E. quadripustulata from the genus diagnosis, see Roewer 1923), and all legs of equal robustness. Like E. quadripustulata , E. rooneyi sp. nov. has the same overall body coloration; however E. quadripustulata has yellow markings in the form of four distinct lateral patches on the DS. E. quadripustulata possesses granulation on all of its free tergites and was described as having all “femora and patellae finely rough” ( Simon 1879: p. 197), unlike the noticeable armature on femora III and IV of E. rooneyi sp. nov. The new species is also similar to the Costa Rican species E. albipustulata Roewer, 1912 (described by Roewer at the erection of the genus Eucynorta and integral in his generic definition) with yellow reticulate pattern on either side of the ocularium, and exhibiting most of the same sexually dimorphic characters. Coloration is different in that areas II and III have fine markings in E. albipustulata , but are mostly free of yellow markings in E. rooneyi sp. nov. E. albipustulata has granules on the free tergites like E. quadripustulata . In contrast to both E. rooneyi sp. nov. and E. quadripustulata , E. albipustulata (after re-examination of SMF holotype) shows no granules on the ventral surface of femur III and only very reduced armature on the ventral surface of femur IV, though this species was originally described “ ♂ 4th femur without secondary sexual characteristics in the form of larger teeth” ( Roewer 1912: 57).

Overall, E. rooneyi sp. nov. proved to be similar to E. quadripustulata and E. albipustulata , which are arguably two taxonomically important species for this genus. But it also has many characteristics in common with other geographically close species currently placed in Eucynorta : E. interposita Roewer, 1954 and E. areolata Roewer, 1947 (from El Salvador and Guatemala, respectively). They share three sexually dimorphic characters with E. rooneyi sp. nov.; specifically, swollen basitarsi on leg I, enlarged chelicerae and armature on femur IV. They also have the same general V-W pattern on the DS, with intrapecific variation. E. rooneyi sp. nov. has only one row of ventral tubercles on femur IV, while E. interposita has two rows of weaker armature (observed in photos of the type specimen, but not specified in the original description). E. rooneyi sp. nov. has fine yellow markings on DS area I, absent in E. interposita , and lacks granules on free tergites. While chelicerae in male E. rooneyi sp. nov. and E. interposita are more robust than conspecific females, this cheliceral dimorphism is more accentuated in E. interposita . E. rooneyi sp. nov. also exhibits differences from E. areolata in that the former has markings on the anterior and lateral regions of DS area I with a small spot in the middle of each side, no markings on areas II and III, unlike the markings of E. areolata , and armature on male femur IV that is much more apparent in E. rooneyi sp. nov., while only small granules were observed on femur IV of E. areolata (again, as observed in photos of the type specimen, not in the original description). As with E. interposita , E. areolata possesses granulation on the free tergites.

Description. Male (holotype, MZSP 71769). Measurements: DS: length: 4.20, width: 3.80; prosoma: length: 2.00, width: 4.00; interocular distance: 0.88; chelicera: 3.75; pedipalp 3.75, femur: 1.00; leg I: 11.25; II: 27.50; III: 16.25; IV: 20.00, femur IV: 6.25 mm.

Coloration: DS and venter deep reddish-brown (Color code 41), markings light yellow (86). Markings form fine reticulate patterns on either side of the ocularium, and a V-pattern in the scutal groove, extending to fine outlines on anterior and lateral sides of area I, with a single spot in the center of each half of area I. The reticulate pattern also extends slightly posteriorly along the lateral margins, adjacent to the hind coxae. There are fine reticulate markings on area IV, extending to the lateral and posterior margins of DS. Small line markings on free tergites. Areas II and III are otherwise free of markings, except for some individuals having an incomplete midline (see intraspecific variation). Chelicerae, pedipalps, and free tergites are the same base color as the dorsal scutum and venter, plus some dark reddish-brown (44) veining. Legs with similar base color in life, but in ethanol they appear lighter, almost pale-yellow (89), especially near bases (including coxa), elsewhere with greyish (80) netted markings.

Dorsum ( Fig. 1A ; 4C ): DS type beta. Anterior margin smooth with a well-marked paracheliceral apophysis on either side of the chelicerae. Lateral margins smooth. Prosoma smooth, low saddle shaped ocularium, slightly tuberculate. Areas I, II, and IV smooth; area III with a pair of smooth spiniform apophyses, apex acute, and directed slightly backwards. Posterior margin smooth, as are the free tergites. Anal operculum smooth, with sparse setae.

Venter ( Fig. 1B ): Coxa I with two rows of structures, one (three granules) along the proximal anterior margin, the other (six tubercles) in a more ventral row from medial to distal, with adjacent bases. Posterior to these are 15 sparse smaller tubercles. Coxa II with two to five posterior granules. Coxa III: row of six tubercles on posterior margin, becoming larger distally. Coxa IV ventrally smooth. Genital operculum and free sternites smooth, with sparse setae.

Chelicerae ( Fig. 2A ): Dimorphic. Males show varying degrees of enlargement (see intraspecific variation). Bulla laterally rough with one large retrolateral tubercle, 8–9 smaller retrolateral tubercles, and two-three prolateral tubercles on the apical margin. Segment II smooth, distally covered with setae, fixed finger with two broad teeth, one on the distal ventral edge, and one medial. Segment III (movable finger) with a row of eight very low teeth, and minimal intracheliceral space.

Pedipalps ( Fig. 2B–D ): Trochanter elongated, with one ventro-distal tubercle. Femur elongate and laterally compressed, with a row of eight proximal tubercles on the dorsal margin, and a row of fourteen tubercles on the ventral margin, the four most basal being smaller than the rest. Patella with small granules on apical end, and one retro-dorsal tubercle, sparsely covered in setae. Tibia elongated and compressed laterally, widening apically; a row of setae on the dorsal and ventral margins, with a single prodorsal and proventral tubercle on the apical tip. Tarsus with two rows of proventral setae, with the medial seta in each row being larger than the rest, sparsely covered in setae elsewhere. Tarsal claw smooth, half the length of the tibia.

Legs: Viewed dorsally, coxa I with one prolateral large apophysis, and one bifid retrolateral apophysis. Coxa II with one large prolateral apophysis (sometimes bifid, see intraspecific variation), and one smaller retrolateral apophysis. Coxa III smooth. Coxa IV with one rear-curved blunt dorso-apical apophysis. All trochanters are remarkably smooth, with the exception of a small distal retro-ventral apophysis on trochanters I, III, and IV, that of trochanter IV being the largest. Legs I–II smooth. Leg III: femur has a ventral row of 10 granules; patella III has two retrolateral granules. Leg IV: femur has a ventral row of 14–15 relatively blunt tubercles on middle-distal portion ( Figure 2E, F ); patella IV has 6–7 retro-dorsal granules; distal segments smooth. Tarsal segmentation: 6(3):16:10/11:13, basitarsi I swollen.

Penis ( Fig. 3A–C ): VP sub-trapezoidal, narrowing slightly distally. Distal margin slightly concave, lateral margins of VP very slightly concave. There are two regions with ventral mats of T1 microsetae on lateral margins of VP, extending from the distal edge up to the truncus. There are six pairs of macrosetae (MS) on the lateral margins of VP; C1–C2 are enlarged, curved and flattened, slightly spatula-shaped. D1 is spiniform and straight, located adjacent to C2, while D2 is more basal, much reduced and spiniform. A1 is closest to D2 and is slightly larger, while also reduced and spiniform. A2 is the most basal pair of lateral MS, and are approximately twice the length of A1. There is a single pair of MS-B located ventrally on the most basal edge of the VP, near to the truncus, and two pairs of reduced MS-E located ventro-laterally on the VP, near MS-D. Glans almost as wide as VP, with large thumb-like dorsal process; stylus curved without a caruncle, only having an extended crest on the distal end of the stylus.

Female (MZSP 71770). Measurements: DS length: 4.80, width: 4.50; prosoma: length: 3.00, width: 4.50; interocular distance: 0.50; chelicera: 2.20; pedipalp, total 4.20, femur: 1.10; leg I: 10.60; II: 34.20; III: 18.10; IV: 23.40, femur IV: 8.00 mm.

External morphology: DS type alpha. Distitarsi on leg I are not swollen as observed in the male, and all legs are smooth. Chelicerae are noticeably smaller in size than in males.

Ovipositor ( Fig. 3D–F ): The apical end of the ovipositor is smooth, and has four lobes, with ten apical peripheral macrosetae, four vs, six ds. Four (of the six) ds are very close to one another in the sulci between the two dl, and two (of four) vs are very close to one another in the sulci between the two vl. The rest of the macrosetae (ds and vs) are equally spaced, one at the center of the margin of each lobe ( Fig. 3E ). They are all approximately the same length, with a singular point on the apical tip. Below the tip of the macrosetae is a single lateral spinule coming out from the side of the setae near the apex ( Fig. 3F ). This was observed in all the setae on the ovipositor.

Intraspecific variation. Males examined varied in degrees of cheliceral robustness. Some males had very pronounced chelicerae, with lengths comparable to the holotype, while others had chelicerae that were not much larger than in females (+ 0.5 mm). The prolateral apophysis on coxae II varied in form. Some individuals (male and female) had a simple apophysis, while others had bifid apophyses, and in one male it appeared that there were two very close individual apophyses; some specimens are asymmetrical, exhibiting a single apophysis on one side, and a bifid one on the other. The number of ventral granules on femur III in males varied between 10 and 15. Femur IV in males showed variation in the number of ventral tubercles, some males having eight (typically those with the reduced chelicerae size) to up to as many as 20. All males examined were asymmetrical in the number of tubercles on their femora IV, usually one or two more tubercles on the left than on the right femur. Leg I exhibited almost no variation, where all individuals examined had six tarsi with three basitarsi, except for a single male which possessed just two basitarsi. The examination of all available males resulted in a tarsal count of 5–6(2–3):13– 17:10–12:11–14. Coloration was approximately the same across all individuals, with reticulate patterns on either side of the ocularium, a V-shaped marking in the scutal groove between area I and the prosoma, a W-shaped marking behind the spines on area III sometimes joined in the middle giving a complete transverse line, and fine line markings on each side of area IV, and on the lateral margins of the dorsal scutum, and free tergites. The most variation observed in individuals was the degree of a midline. Some individuals possessed an incomplete midline, but more often only a single medial dot, patch, or small line in the center of area II was present.

Interspecific differences in genitalia. Penis: Comparisons between E. rooneyi sp. nov. and E. albipustulata (the latter according to D. Proud, pers. comm.) showed a more elongated VP in the former, with the maximum length being approximately one and a half the maximum width, while the VP of E. albipustulata is more square, with length about the same as width. Like E. albipustulata , E. rooneyi sp. nov. has six lateral penial MS. In E. rooneyi sp. nov. MS-C are spatulate, but not as compressed and flattened as in E. albipustulata . The position of the two MS-A pairs is different between these species: on E. albipustulata they are very close, arranged dorso-laterally instead of along the lateral margin, while in E. rooneyi sp. nov. they are more separated, with the most apical pair being placed in middle of the lateral edge of the VP. In both species VP has slightly concave apical margin. They both also bear ventral mats of microsetae along the lateral margins, but E. rooneyi sp. nov. has type 1 microsetae (T1), while T4 is observed in E. albipustulata . The glans and stylus in E. rooneyi sp. nov. is longer than VP, this is not observed in E. albipustulata .

Ovipositor: Comparisons between E. rooneyi sp. nov. and congeners were not possible due to lack of published data on any other Eucynorta species. Comparing it to Cynorta bromeliacia Goodnight & Goodnight, 1947 and Cynorta dentipes F.O. Pickard-Cambridge, 1904 (examined by Walker & Townsend 2014) showed that all three species have four smooth lobes with more ds than vs; however, C. bromeliacia has more ds than E. rooneyi sp. nov. and C. dentipes , with up to nine ds instead of six. All peripheral setae exhibited the same morphology in the referenced species, with a lateral spinule present just below the single apical tip. Unlike the other two, C. dentipes has all macrosetae equidistant from each other, while E. rooney sp. nov. and C. bromeliacia have four ds in the sulci between the two dl.

Natural history and conservation status. This species is currently endemic to Cusuco National Park, found at mid- to high elevation (1600–1800 m), in mixed montane rainforest dominated by pine ( Pinus maximinoi and P. oocarpa ) and broadleaf trees (such as Liquidambar styracuflua ), with an understory of tree ferns ( Cyathea species), palms (Chameadorea spp., Cryosophila williamsii, Geonoma undata, and Synechanthus fibrosus ), and others, such as guaruma ( Cecropia spp.) ( Fig. 4A, B ). From June to August, males and females were active at night, commonly collected from understory vegetation, and rarely found in the leaf litter. It is worth noting that E. rooneyi sp. nov. has predominantly been sampled in the core zone of Cusuco National Park. This park is relatively small (234.7 km 2) and suffers from pronounced deforestation pressures that might put this species at risk. Combined collections of B.N. Damron and S.J. Longhorn for three intensive seasons (10 months of field work in total, between June and August) yielded scarcely 39 individuals. This could be an indication of the rarity or the relatively low population size for this new species, insofar as our sampling is a reasonable indication of abundance. Additional surveys and collection efforts are required to accurately determine if it may be experiencing negative pressures from human-derived habitat disturbance.

Figures

FIGURE 1. Dorsal scutum and venter of Eucynorta rooneyi sp. nov., holotype male (MZSP 71769); inverse coloring was used to show markings on dorsal scutum. A. Dorsal view. B. Ventral view. C. Lateral view. Scale bars = 2 mm.

FIGURE 2. Appendages of Eucynorta rooneyi sp. nov., holotype male (MZSP 71769). A. Chelicerae, anterior view. B–D, Left pedipalp, B. Dorsal view. C. Lateral view. D. Ventral view. E–F. Leg IV, from trochanter to tibia. E. Ventral view. F. Dorsal view. Scale bars = 1 mm (A–D), 3 mm (E–F).

FIGURE 3. Distal portion of penis and ovipositor of Eucynorta rooneyi sp. nov. A–C: Penis (MZSP 71769). A. Lateral view. B. Dorsal view. C. Ventral view. D–F: Ovipositor (MZSP 71770), with ds to the left. D. Lateral view. E. Apical view. F. Magnified view of setae. Scale bars = 100 µm (A–C); 50 µm (D–F).

FIGURE 4. A–B: Field sites within Parque Nacional Cusuco, inhabited by Eucynorta rooneyi sp. nov. A. Field site near to base camp, at approximately 1600 m asl. B. Field site near to a temporary camp, approximately 1800 m asl. C. Live male of Eucynorta rooneyi sp. nov.