Ceratoppia offarostrata, Lindo, Zoe, 2011

Lindo, Zoe, 2011, Five new species of Ceratoppia (Acari: Oribatida: Peloppiidae) from western North America, Zootaxa 3036, pp. 1-25: 17-20

publication ID

http://doi.org/ 10.5281/zenodo.204548

persistent identifier

http://treatment.plazi.org/id/166F87A3-FC04-DF53-FF08-FAB8FB09686F

treatment provided by

Plazi

scientific name

Ceratoppia offarostrata
status

n. sp.

Ceratoppia offarostrata  n. sp.

Material examined. Holotype: Adult female. Canada, British Columbia, Vancouver Island, Upper Walbran Valley, 48 ° 39 ’N, 124 ° 35 ’W, 25 July 2005 (Z. Lindo & N.N. Winchester) from bark scraping at 16 m in western redcedar ( Thuja plicata D. Don  ); deposited in the CNC, type No. 23976. Paratypes: 20 with same data as holotype. Canada, British Columbia, Vancouver Island, Pacific Rim National Park Reserve, Rainforest Trail (49 °00’N, 125 ° 37 ’W), 13 October 2005 (V. Behan-Pelletier), one from moss and bark at breast height on western redcedar. Paratypes deposited in the CNC, PFC, RNC, and ZLC.

Other material examined. Canada, British Columbia: Graham Island, Haida Gwaii (53 ° 28 ’N, 132 ° 25 ’W); Cape St. James, Gwaii Haanas National Park Reserve, Haida Gwaii (51 ° 56 ’N, 131 ° 1 ’W).

Etymology. The specific epithet is from the Latin “ offa ” meaning “lump”, and refers to the prominent bump on the rostrum seen in lateral view.

Diagnosis. Adult. Total length 570–640 µm, with character states of Peloppiidae  ( Grandjean, 1954; as Ceratoppiidae  ), and character states of Ceratoppia  as described above. This species can be differentiated from other Ceratoppia  by the presence of a single pair of hypostomal setae; two pairs of posterior notogastral setae conspicuous (p 1, p 3); rostrum rounded with many denticles but without prominent medial tooth, or indentation; rostrum in lateral view with prominent ‘bump’; lamellae with short cusps not reaching the insertion of rostral setae; interlamellar setae distinctly longer than lamellae.

Description. Adult. ( Figs. 32View FIGURES 32 – 33 –38)

Measurements: Mean total length: females (n = 6) 625 µm (range 620–640); males (n = 4) 575 µm (range 570–580) ( Figs. 32View FIGURES 32 – 33 –34). Mean notogastral width: females (n = 6) 360 µm (range 330–370); males (n = 4) 333 µm (range 310–350).

Integument: Smooth to microtuberculate. Integument laterad of bothridial setae between acetabula III and IV tuberculate. Prodorsum: Rostrum without medial tooth, dentate with five to eight teeth ( Fig. 32View FIGURES 32 – 33, Figs. 37–38). Seta ro 80 µm long, acuminate, thick, barbed, extending well beyond rostrum (Figs. 36–38). Lamellae about 220 µm long to end of cusps, not reaching insertion of ro (Fig. 37). Lamellar cusps about 61 µm long. Seta le about 110 µm long, barbed, tapering, extending anteriorly well beyond rostrum (Figs. 36–38). Seta in barbed, 260 µm long, extending anteriorly beyond tips of lamellae (Fig. 37). Mutual distance of setal pairs ro –ro, le –le, and in –in, about 68, 60, and 77 µm, respectively. Seta ex not observed; alveoli removed anteriolaterally from bothridial. Bothridial seta 160 µm long, with long barbs (Fig. 34). Lateral aspect of prodorsum: Pedotectum I well developed, rounded and crenulate anteriorly, with dorsal cusp about 18 µm long. Prominent bump on the rostrum seen in lateral view (Figs. 37–38). Lateral ridge from base of acetabula I to base of rostrum (Fig. 38). Notogaster: Subequal length to width, (ratio l:w = 1.01: 1); hysterosoma often fattened with four eggs of considerable size (about 280 µm long). Notogastral setae reduced to alveoli, except for two pairs of posterior setae. Posterior notogastral setae p 1 about 55 µm long (range 48–63, n = 11), barbed; setae p 3 about 46 µm long (range 40–55, n = 10) barbed ( Fig. 32View FIGURES 32 – 33, Fig. 34).

FIGURES 34–38. Ceratoppia offarostrata  n. sp., scanning electron microscope images of adult. 34, habitus, dorsal aspect, bothridial setae (bo), interlamellar setae (in), lamellar seta (le), posterior setae (p 1, p 3); 35, habitus, ventral aspect, posterior setae (p 3), adanal setae (ad 1, ad 2); 36, habitus, frontal aspect, bothridial setae (bo), interlamellar setae (in), lamellar seta (le), rostral setae (ro); 37, prodorsum, dorsal aspect, interlamellar setae (in), lamellar setae (le), rostral setae (ro), and rostral bump (a); 38, rostrum, anterio –lateral aspect, showing rostral bump (a), rostral setae (ro), lamellar setae (le), and lateral carina (ca). Scale bars = 300 µm (Fig. 34, 35), 200 µm (Fig. 36), 100 µm (Fig. 37), and 50 µm (Fig. 38).

Lyrifissures im, ip, ih, and ips present, all about 8 µm long. Ventral region: Coxisternal setae smooth or with a few barbs, acuminate; formula (epimeres I to IV) 3 – 1–3 – 3 ( Fig. 33View FIGURES 32 – 33). Setae lengths as follows: 1 a, 1 b, 1 c about 35, 78, 93 µm, respectively, 2 a, 3 a, 3 b, 3 c about 32, 21, 94, 21 µm, respectively, and 4 a, 4 b, 4 c about 37, 35 and 21 µm, respectively. Six pairs of genital setae ranging in length from 18–25 µm, with longest g 5 and g 6, setose. Aggenital seta about 21 µm long, setose, acuminate. Two pairs of anal setae about 21 µm long, acuminate. Three pairs of adanal setae; ad 3 24 µm, ad 1 34 µm and ad 2 30 µm, all barbed ( Fig. 33View FIGURES 32 – 33, Fig. 35). Lyrifissure iad 8 µm long, anterior to ad 3. Gnathosoma: Subcapitular mentum without tectum; one pair of h setae about 52 µm long; gnathosomal setae m 38 µm long, and a about 31 µm long.

Legs: Ratio of leg IV to body length about 0.65: 1. Approximate lengths of leg segments (femur, genu, tibia, tarsus; in µm): I 143, 35, 93, 134; II 111, 27, 79, 114; III 73, 35, 94, 117; IV 75, 50, 107, 150. Pretarsus tridactylous with large smooth empodial and slightly thinner lateral claws. Setation (I –IV, number of solenidia in parentheses): trochanters 1 – 1–2 – 1; femora 5 – 4 – 3 – 2; genua 3 (1)– 3 (1)– 2 (1)– 3; tibiae 4 (2)– 4 (1)– 3 (1)– 3 (1); tarsi 20 (2)– 15 (2)– 15 – 12; setation indicated in Table 2. Seta d absent from genua and tibiae of adult, no evidence of retention associated with socket of solenidion ϕ 1. Most of leg setae conspicuously barbed. Seta ft” on tarsus leg IV prominent, thick, barbed. Femur of leg III –IV with well developed ventral keel; femur leg I –II relatively slender without ventral keel, with bumpy cerategument anteriorly. Tibiae solenidion ϕ 1 of leg I flagellate, anterior of ϕ 2 which is straight, sharp. Leg II tarsal solenidia ω 1 and ω 2 subequal, straight, relatively short; tibial solenidia ϕ straight, twice as long as genua solenidia σ. Porose areas dorsolateral and antiaxial on femora of all legs, and trochanters III, IV. Single specimen with deformed right leg I tarsus.

Remarks. Ceratoppia offarostrata  n. sp. and C. sexpilosa  share the characteristic rostral ‘bump’, but C. offarostrata  differs from C. sexpilosa  in the number and expression of posterior notogastral setae. Ceratoppia offarostrata  has two pairs of posterior notogastral setae (p 1 and p 3 expressed) versus three pairs (h 1, p 2, p 3 expressed) in C. sexpilosa ( Hammer 1967)  . Ceratoppia offarostrata  also lacks a prominent medial rostral tooth; other similar species which lack medial rostral tooth include C. sphaerica  and C. hoeli Thor, 1930  , but these lack the rostral ‘bump’. Ceratoppia hoeli  also differs from C. offarostrata  in having simple posterior seta, very short lamellar cusps, and long lamellar setae ( Thor 1930). Ceratoppia sphaerica  is quite similar to C. offarostrata  (two pairs of medium sized, barbed p 1, p 3 setae) but in addition to lacking the rostral bump, C. sphaerica  is much larger in size (0.7–1.0 mm) ( Hammer 1955; Seniczak & Seniczak 2010). A full diagnosis and comparison of C. offarostrata  with C. sphaerica  is problematic though as the original type specimen of C. sphaerica  as described by L. Koch (1879) is unknown; the original drawings and text are poor. The consensus of character states for C. sphaerica  are: large body size (700–1000 um); dark (almost black) in colour; prodorsum rounded anteriorly with a serrate or dentate edge; lamellar setae longer than rostral setae; interlamellar setae as long as prodorsum, longer than lamellae; lamellae not reaching insertion of rostral setae, with short cusps; two pair, rather short posterior notogastral setae (p 1 and p 3) ( Trägårdh 1906; Gilyarov 1975; Hammer 1952; 1955; Seniczak & Seniczak 2010).

Distribution. Ceratoppia offarostrata  n. sp. occurs in low frequency and low abundance in samples collected from the Walbran Valley on Vancouver Island, British Columbia. Specimens collected from type locality in Walbran Valley are associated exclusively with bark scraping samples on western redcedar. Similarly, specimens collected from Pacific Rim National Park, British Columbia are from moss and bark samples collected from western redcedar trees at breast height. Association with bark habitats, and the possibility of host tree specificity, may explain the low occurrence of collection for this species. The distribution range of C. offarostrata  appears limited to coastal locations on Vancouver Island and Haida Gwaii. Specimens collected from Haida Gwaii have slightly shorter posterior setae and reduced rostral bump. The distributional patterns of C. sphaerica  suggest this species is limited to arctic and subarctic areas in western Canada; C. offarostrata  may be southern variant subspecies of C. sphaerica  ; further sampling of C. offarostrata  and comparison with C. sphaerica  is warranted.

CNC

Canadian National Collection of Insects, Arachnids, and Nematodes