Severianoia annamensis Van Luc and Spiridonov, 1993

Carreno, Ramon A., 2017, New species of Hammerschmidtiella Chitwood, 1932, and Blattophila Cobb, 1920, and new geographical records for Severianoia annamensis Van Luc & Spiridonov, 1993 (Nematoda: Oxyurida: Thelastomatoidea) from Cockroaches (Insecta: Blattaria) in Ohio and Florida, U. S. A., Zootaxa 4226 (3), pp. 429-441 : 438-439

Severianoia annamensis Van Luc and Spiridonov, 1993

( Table 3 )

Several specimens of P. surinamensis collected in southern Florida were infected with S. annamensis ( Table 3 ).

Taxonomic Summary

Host: Pycnoscelus surinamensis (Linnaeus, 1758)

Locality: John Pennecamp Coral Reef State Park, Key Largo, Florida (25 ̊7’38.3”N, 80 ̊24’31.2”W).

Prevalence = 15%; mean intensity = 2.8

Site of infection: hindgut

Specimens deposited: Vouchers HWML 99923 1 male, 1 female; HWML 99924 , three females, John Pennecamp Coral Reef State Park, Key Largo , Florida.

Voucher DNA sequence: 18S small subunit ribosomal RNA gene, partial sequence Genbank accession number KX752431 .

General observations of S. annamensis from Florida . Although esophageal proportions are slightly larger (with overlap) in the Florida specimens (415–503 µm in Florida specimens vs. 320–460 µm in original description), other measurements overlapped more broadly with those provided for S. annamensis , and the specimens were determined to be morphologically indistinguishable. The type species, Severianoia severianoi ( Schwenck, 1926) Travassos, 1929 has much larger esophageal length (525–706 µm in original description by Schwenck and redescription by Kloss, 1966). Female body length (3000–4366 µm) is also greater in S. severianoi . A report of a single female originally identified by Chitwood (1932) as S. severianoi from P. surinamensis in southern Florida (Paradise Key, Everglades National Park) included measurements that are more consistent with S. annamensis ( Van Luc & Spiridonov, 1993) . The tail length of Chitwood’s female (110 µm) fell well out of the range of the Key Largo specimens (141–159 µm). However, tail length in the original description of S. severianoi (100–200 µm) overlaps with both species ( Schwenck, 1926; Van Luc and Spiridonov, 1993), and re-measurement of Chitwood’s specimen ( US National Parasite Collection code USNPC 31893 ) yielded a tail length of 147 µm. The Severianoia sp. documented from the Galápagos Islands also yielded overlapping measurements of both males and females of S. annamensis and more closely resembles S. annamensis than S. severianoi ( Sinnott et al., 2015) .

Tables

TABLE 3. Morphometric measurements (in micrometers) for Severianoia annamensis Van Luc and Spiridonov, 1993. The mean and standard deviation are followed by range.

Character	Females (n = 6)	Males (n = 5)
Body length	3302 ± 383 (2750 – 3875)	735 ± 100 (600 – 840)
Maximum width	272 ± 21 (250 – 305)	94 ± 17 (75 – 110)
Buccal cavity (length)	15 ± 3 (13 – 21)	6 ± 1 (5 – 8)
Oral annule length	6 ± 2 (5 – 9)	-
Oral annule width	24 ± 2 (21 – 26)	-
Second annule length	17 ± 2 (15 – 18)	-
Second annule width	48 ± 2 (47 – 51)	-
Nerve ring	173 ± 12 (162 – 190)	101 ± 2 (100 – 103)
Excretory pore	Not observed	300
Esophagus	450 ± 29 (415 – 503)	160 ± 19 (139 – 182)
Corpus length	306 ± 17 (288 – 338)	92 ± 13 (79 – 109)
Corpus maximum width	56 ± 3 (53 – 60)	17 ± 2 (14 – 19)
Isthmus length	25 ± 5 (18 – 30)	25 ± 2 (23 – 28)
Bulb length	117 ± 8 (110 – 130)	45 ± 6 (38 – 50)
Bulb width	123 ± 7 (113 – 132)	36 ± 4 (30 – 41)
Vulva from anterior end	2265 ± 50 (2230 – 2300)	-
Vulva from posterior end	1191 ± 543 (808 – 1575)	-
Vagina length	115	-
Tail length	152 ± 8 (141 – 159)	50 ± 1 (48 – 51)
Egg length	80 ± 4 (74 – 83)	-
Egg width	30 ± 2 (27 – 31)	-
a	12 ± 2 (10 – 15)	8 (7 – 8)
b	7 ± 1 (6 – 9)	5 ± 1 (4 – 6)
c	23 ± 3 (19 – 28)	15 ± 2 (12 – 17)
V	66 ± 10 (59 – 73)	-
Spicule length	-	28 ± 4 (23 – 33)