Ceratoppia indentata, Lindo, Zoe, 2011

Lindo, Zoe, 2011, Five new species of Ceratoppia (Acari: Oribatida: Peloppiidae) from western North America, Zootaxa 3036, pp. 1-25 : 4-7

Ceratoppia indentata n. sp.

Material examined. Holotype: Adult female. Canada, British Columbia, Vancouver Island, Upper Walbran Valley (48°39’N, 124°35’W), 10 September 2004 (Z. Lindo) from forest floor below western redcedar ( Thuja plicata D. Don ); deposited in the Canadian National Collection of Insects, Arachnids and Nematodes, Ottawa, Ontario, Canada ( CNC), type No. 23974. Paratypes: ten with same data as holotype. Canada, British Columbia, Vancouver Island: Upper Carmanah Valley (48°44’N, 124°37’W), 3 July 1990 (N.N. Winchester), ten from forest floor below Sitka spruce ( Picea sitchensis (Bong.) Carr. ). USA: Washington, Hoh Valley, Olympic National Park (47°52’N, 123°54’W), 10 September 1983 (A. Fjellberg), seven from litter and humus below Sitka spruce. Oregon, Curry County, Alfred A. Loeb State Park (42°6’N, 124°11’W), 12 August 1985 (E.E. Lindquist), 11 from moss and lichen around tan-oak and willow trunks; Oregon, Lane County, H.J. Andrews Experimental Forest, Willamette National Forest (44°10’N, 123°13’W), 15 May 1984 (D.S. Chandler), 18 from rotting logs on forest floor. Paratypes deposited in the CNC, PFC, RNC, and ZLC.

Other material examined. Canada, British Columbia: Caycuse (48°53’N, 124°21’W); Broken Island Group (48°52’N, 12419’W); Barkley Sound (48°58’N, 124°6’W); Bamfield Marine Station (48°45’N, 125°10’W); Hesquiat Peninsula Provincial Park (49°22’N, 126°31’W); Sydney Inlet, Clayoquot Sound (49°30’N, 126°17’W); Campbell River, STEMS Research site (50°03’N, 125°26’W); Brooks Peninsula (50°7’N, 127°46’W); Lax Kw'alaams (54°33’N, 131°25’W). USA, Washington: Quinault Rain Forest, Olympic National Forest (47°32’N, 123°40’W); Queets River, Olympic National Park (47°32’N, 124°21’W). Oregon: Tillamook State Forest (45°30’N, 123°39’W); Siuslaw National Forest (44°21’N, 123°48’W); Alsea Falls (44°20’N, 123°31’W); Mary’s Peak Botanical Special Interest Area (44°30’N, 123°32’W); Siskiyou National Forest (42°30’N, 123°57’W). California: Jedediah Smith Redwood State Park (41°46’N, 124°5’W); Angelo Coast Range Reserve (39°40’N, 123°39’W); Van Damme Beach State Park (39°16’N, 123°43’W); Salt Point State Park (38°57’N, 123°32’W); Purisima Creek Redwoods Regional Open Space near Halfmoon Bay (37°24’N, 122°21’W).

Etymology. This species is named for the deeply indented rostrum with large, single, inset medial denticle.

Diagnosis. Adult. Total length 560–650 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 distinct invaginated rostrum with a thin, somewhat flexible, medial denticle, and many lateral denticles; interlamellar setae distinctly shorter than the lamellae, only reaching the base of the lamellar cusps; one pair of hypostomal setae; lamellae not reaching the insertion of the rostral setae.

Description. Adult. ( Figs. 1 –7)

Measurements: Mean total length: females (n = 5) 628 µm (range 600–650); males (n = 5) 584 µm (range 560–600) ( Figs. 1–2 ). Mean notogastral width: females (n = 5) 376 µm (range 360–380); males (n = 5) 352 µm (range 340–380).

Integument: Smooth to microtuberculate. Integument laterad of bothridial setae between acetabula III and IV tuberculate. Prodorsum: Rostrum strongly indented (18 µm deep × 13 µm wide), with single sub–triangular medial denticle at base of indentition and 7–11 sharp denticles along margin and laterally ( Fig. 1 , Fig. 5). Lateral ridge extending from base of acetabulum I to rostrum (Fig. 5). Seta ro 68–83 µm long, thick, acuminate, barbed, extending well beyond rostrum ( Fig. 1 , Figs. 5, 7). Lamella about 227 µm long to end of cusps, not reaching insertion point of ro, striate at base (Fig. 7). Lamellar cusps about 91 µm long with small lateral denticle. Seta le about 94 µm long, thick, barbed, inserted medially on lamellar cusp and extending anteriorly beyond rostrum (Fig. 7). Seta in barbed, 144 µm long, not reaching tip of lamella ( Fig. 1 , Fig. 7). Mutual distance of setal pairs ro–ro, le–le, and in–in, about 47, 40, and 66 µm, respectively. Seta ex not observed; alveoli well removed anteriolaterally from bothridia ( Fig. 1 ). Bothridial seta 191 µm long, thin with long barbs, tapering to point. Lateral aspect of prodorsum: Pedotectum I well developed, dentate anteriorly, with dorsal cusp about 20 µm. Notogaster: Subequal length to width; hysterosoma often fattened with 1– 7 eggs of considerable size (about 260 µm long). Notogastral setae reduced to alveoli, except for two pairs of posterior setae ( Fig. 1 , Figs. 3–4). Alveoli with porose areas ( Fig. 1 ). Posterior notogastral setae h1, about 103 µm long (range 75–118, n = 13), barbed; setae p3 about 78 µm long (range 60–95, n = 16), barbed; p1 alveoli well removed posteriorly and mediad to h1; p2 alveoli mediad to p3. Lyrifissures im, ip, ih, and ips present, all about 10 µm long. Ventral region: Apodeme IV forming shallow furrow with minitectum on anterior portion ( Fig. 2 ), thinning near genital aperture as described by Grandjean (1970). Epimeral setae smooth or with a few barbs, acuminate, relatively long; formula (epimeres I to IV) 3–1–2–3 ( Fig. 2 ). Setae lengths as follows: 1a, 1b, 1c about 25, 47, 75 µm, respectively, 2a, 3a, 3b, about 25, 24, 61, µm, respectively, and 4a, 4b, 4c about 27, 25 and 25 µm, respectively. Six pairs of genital setae ranging in length from 15–25 µm, with longest g4 and g5, setose. Aggenital seta about 22 µm long, setose, asymmetry observed in a single specimen (two pairs of aggenital setae on right side). Two pairs of anal setae about 22 µm long, asymmetry observed in single specimen with three pairs of anal setae on left side. Three pairs of adanal setae; ad3 about 26 µm, thin, barbed, different from ad1 and ad2 which are thicker, barbed, about 51 and 41 µm long, respectively ( Fig. 2 , Fig. 3). Lyrifissure iad 8 µm long, anterior to ad3. Gnathosoma: Subcapitular mentum without tectum; one pair of setae h about 36 µm long; gnathosomal setae m 38 µm long, and setae a about 27 µm long.

FIGURES 3–7. Ceratoppia indentata n. sp., scanning electron microscope images of adult. 3, habitus, ventral aspect; 4, habitus, dorsal aspect (setae h1 of left side broken); 5, rostrum, anterio–dorsal aspect, showing indented rostrum (a) with teeth, minute stub of seta d on genu leg I (b), rostral setae (ro), lamellar setae (le), and lateral carina (ca); 6, habitus, lateral aspect; 7, prodorsum in dorsal aspect, interlamellar setae (in), lamellar setae (le), and rostral setae (ro). Scale bars = 300 µm (Figs. 3–4, 6) and 100 µm (Fig. 5, 7).

Legs: Ratio of leg IV to body length about 0.7:1. Approximate lengths of leg segments (femur, genu, tibia, tarsus; in µm): I 156, 38, 83, 165; II 128, 28, 83, 138; III 72, 36, 100, 133; IV 87, 63, 124, 176. 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 4(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 retained as a small stub on genua leg I (Fig. 5), but absent from tibiae of adult; no evidence of retention associated with socket of solenidion 1, as illustrated for Ceratoppia bipilis ( Grandjean 1935) . Leg I genua setae l” thick, barbed and spinose compared to other leg I setae (Fig. 5). Leg I tarsal solendia ω1 and ω2 thin, flagellate. All tarsal setae barbed except p which is simple, straight, short on leg I, increasing in length and becoming curved, almost flagellate on subsequent legs.

Trochanter Femur Genu Tibia Tarsus

Leg 1 v' d bv" (l) v' d * (l) v' σ (l) (v) d ‡ ϕ1 2 (ft)(pl)(tc)(p)(u) s (a)(pv) e ω1 ω2 (it)(v) Leg 2 v' d bv" (l) l' (v) σ (l) (v) ϕ (ft)(tc)(p)(u) s (a)(pv) ω1 ω2 (it) Leg 3 v' l' d ev' l' l' v' σ l' (v) ϕ (ft)(tc)(p)(u) s (a)(pv)(it) Leg 4 v' d ev' l' v' l' (v) ϕ ft" (tc)(p)(u) s (a)(pv)

* d setae present in Ceratoppia indentata and C. valerieae , retained as small stub.

‡ d setae present in some specimens of C. indentata and C. valerieae , associated with solenidia φ1.

Remarks. Ceratoppia indentata n. sp. is similar to C. incisa Kaneko & Aoki, 1982 with interlamellar setae distinctly shorter than the lamellae, only reaching the base of the lamellar cusps, and a distinct invaginated rostrum. Ceratoppia indentata n. sp. differs from C. incisa by having longer, barbed posterior setae (h1, p3), barbed epimeral setae, longer lamellar and rostral setae, shorter lamellae not reaching the insertion of the rostral setae, and in the shape of the rostral incision. Ceratoppia incisa rostral indentation is described as having two incisions,

the bottoms of which are broadly rounded ( Kaneko & Aoki 1982), whereas C. indentata clearly has a single invagination of the rostral margin, with a thin, somewhat flexible, medial denticle, and many lateral denticles. Ceratoppia indentata has an unusual pattern of notogastral expression in that h1 rather

than p1 are expressed in conjunction with p3. The dominant form of notogastral expression among the Ceratoppia is two pairs of posterior seta (p1 and p3) expressed with h1, alveolus, but three pairs of posterior notogastral seta expressed (h1, p2, p3) is observed in C. sexpilosa ( Seniczak & Seniczak 2010) . In both C. bipilis and C. quadridentata arctica , the h1 alveolus is directly anterior and dorsal to p1, while in C. indentata the p1 alveoli are well removed posteriorly and mediad to h1. Therefore it is unlikely that p1 and h1 setae are simply shifted in position. It is more likely that the posterior notogastral seta expression of C. indentata is derived from the subdominant form of expression with p2 secondarily lost.

Distribution. Ceratoppia indentata n. sp. is the dominant Ceratoppia on the forest floor throughout most of the Pacific Northwest coastal temperate rainforest biogeoclimatic zone. Widely distributed and abundant on Vancouver Island, British Columbia, Canada, the distribution extends southward through to northern California, remaining relatively coastal. The H.J. Andrews Experimental Forest in Oregon appears to be the most inland site where C. indentata has been observed, where it was recorded (as Ceratoppia sp.) as frequent, but never abundant ( Moldenke & Fitcher 1988 – see their Figs. 205–207). Northern records appear less common, but C. indentata is recorded from the north coast of British Columbia (Lax Kw’alaams, Port Simpson). Species in the southern range appear with morphological variation; specimens observed from California are larger and darker than northern specimens, interlamellar setae are relatively slightly longer, and posterior setae p1 are relatively slightly shorter. Loeb State Park, in southern Oregon has both variants co–occurring. The habitat of Ceratoppia indentata n. sp. appears to be mixed or single litter from both conifer and deciduous trees, moss, and lichens; often collected near beaches, small creeks, river mouths or ravines suggests a moist habitat preference.

Figures

FIGURES 1 – 2. Ceratoppia indentata n. sp., adult female. 1, Dorsal aspect; 2, Ventral aspect. Legs removed. For description of setae see Materials and methods. Scale bars = 300 µm.