PHYLOGENETIC ANALYSIS OF THE METASTRONGYLOIDEA (NEMATODA: STRONGYLIDA) INFERRED FROM RIBOSOMAL RNA GENE SEQUENCES

Phylogenetic relationships among nematodes of the strongylid superfamily Metastrongyloidea were analyzed using partial sequences from the large-subunit ribosomal RNA (LSU rRNA) and small-subunit ribosomal RNA (SSU rRNA) genes. Regions of nuclear ribosomal DNA (rDNA) were amplified by polymerase chain reaction, directly sequenced, aligned, and phylogenies inferred using maximum parsimony. Phylogenetic hypotheses inferred from the SSU rRNA gene supported the monophyly of representative taxa from each of the 7 currently accepted metastrongyloid families. Metastrongyloid taxa formed the sister group to representative trichostrongyloid sequences based on SSU data. Sequences from either the SSU or LSU RNA regions alone provided poor resolution for relationships within the Metastrongyloidea. However, a combined analysis using sequences from all rDNA regions yielded 3 equally parsimonious trees that represented the abursate Filaroididae as polyphyletic, Parafilaroides decorus as the sister species to the monophyletic Pseudaliidae, and a sister group relationship between Oslerus osleri and Metastrongylus salmi. Relationships among 3 members of the Crenosomatidae, and 1 representative of the Skrjabingylidae (Skrjabingylus chitwoodorum) were not resolved by these combined data. However, members of both these groups were consistently resolved as the sister group to the other metastrongyloid families. These relationships are inconsistent with traditional classifications of the Metastrongyloidea and existing hypotheses for their evolution

Evolutionary Relationships among the Protostrongylidae (Nematoda: Metastrongyloidea) as Inferred from Morphological Characters, with Consideration of Parasite-Host Coevolution

The phylogeny of nematodes in the family Protostrongylidae (Nematoda: Metastrongyloidea) was reconstructed by cladistic analysis of 28 binary and multistate characters derived from comparative morphology. Analyses were hierarchical, and examined (1) relationships among genera, including 13 ingroup taxa and Metastrongylidae as an outgroup (single tree, 78 steps, consistency index [CI]=0.705); and (2) relationships among genera and species groups including 21 ingroup taxa and Metastrongylus apri as an outgroup (single tree, 76 steps, CI=0.582). In the species-level tree, Protostrongylidae was divided into 2 major clades, one containing the subfamilies Muelleriinae (including the recently described Umingmakstrongylus pallikuukensis) Elaphostrongylinae, and the Varestrongylinae (excluding Pneumocaulus kadenazii). Varestrongylus was paraphyletic as it included Pneumostrongylus calcaratus. The second major clade consisted of a paraphyletic group containing Protostrongylus spp. and Spiculocaulus leuckarti and, basal to this subclade, several other individual protostrongylid lineages. The various subclades generally correspond to the subfamilial divisions of the Protostrongylidae. The Neostrongylinae, however, is not supported as Neostrongylus and Orthostrongylus are not sister groups. Based on a large number or hypothesized synapomorphies, the elaphostrongylines appear to be a highly derived group of protostrongylids, a feature potentially correlated with their habitat localization in muscular and nervous tissues. The generic-level tree retained most of the primary structure revealed among the species but excluded the carestrongylines from the Muelleriinae + Elaphostrongylinae subclade. Artiodactyles of the family Cervidae are considered basal hosts for protostrongylids; secondary colonization in Caprini, Rupicaprini and among lagomorphs is postulated

Zonothrix columbianus Adamson & Buck 1989

Zonothrix columbianus Adamson & Buck, 1989 (Thelastomatoidea: Pseudonymidae) Males and females of this species were recovered from Tropisternus collaris and T. blatchleyi blatchleyi (Table 1). Measurements (in micrometers). Males (n = 9): Body length 1251 ± 165 (980–1410); maximum width 69 ± 6 (60–78); buccal cavity 7 ± 1 (5–8); length of buccal capsule 7 ± 2 (5–9); width of buccal capsule 16 ± 2 (14–18); nerve ring 159 ± 12 (135–170); excretory pore 322 ± 18 (290–338); esophagus 222 ± 12 (201–235); corpus 171 ± 10 (153–181); corpus maximum width 17 ± 2 (15–21); isthmus 14 ± 4 (10–20); bulb length 38 ± 2 (35–40); bulb width 37 ± 2 (34–40); tail 39 ± 8 (28–53); body width at tail 25 ± 2 (23–28); spicule 24 ± 4 (18–28); gubernaculum 16 ± 5 (13–20); a = 18 ± 2 (15–20); b = 6 ± 1 (5–6); c = 33 ± 7 (26–44). Female (n = 15): Body length 3001 ± 282 (2375–3775); maximum width 206 ± 25 (169–250); buccal cavity 17 ± 2 (15–21); oral annule length 12 ± 2 (10–15); oral annule width 40 ± 3 (36–45); second annule length 21 ± 4 (17–28); second annule width 68 ± 5 (60–76); nerve ring 243 ± 25 (225–260); excretory pore 561 ± 117(415–725); esophagus 371 ± 32 (325–410); corpus length 291 ± 28 (256–340); corpus maximum width 43 ± 3 (40–49); bulb length 82 ± 8 (70–95); bulb width 82 ± 6 (73–95); vulva from anterior end 1859 ± 280 (1391–2425); vulva from posterior end 1068 ± 114 (860–1260); distance between vulva and anus 767 ± 104 (560–910); tail 286 ± 31 (250–335); body width at tail 115 ± 19 (90–145); egg length 69 ± 4 (63–78); egg width 44 ± 3 (40 – 48); a = 15 ± 2 (12–18); b = 8 ± 1(7–9); c = 10 ± 2 (8–13); V = 64 ± 4 (57–69). The morphology of our specimens together with the measurements presented above overlap consistently with those of T. columbianus. The swollen cuticular annulations and longer tail (84 – 120 µm vs. 250 – 335 µm) differentiate this species from the only other currently known North American species, Zonothrix tropisterna Todd, 1942, found in Tropisternus numbatus Say, 1823 (Todd, 1942; Adamson & Buck, 1990). Reported hosts for Z. columbianus include Tropisternus columbianus, T. lateralis marginatus, and Hydrobius fuscipes (Adamson & Buck, 1990; Adamson et al., 1992). Thus, T. collaris and T. b. blatchleyi represent new hosts for Z. columbianus. The typical presence of worms in the host has been reported as exactly one male and one female (Adamson et al., 1992). In the present study, a similar pattern was found, with the mean intensity of males of Z. columbianus in T. collaris being 1 (8 infected) and females 1.2 (11 infected). Six of the 11 infected T. collaris had one male and one female, 3 had no males and one female, two had 1 male and 2 females, and 6 were uninfected (Table 1). The 2 infected T. blatchleyi both had one male and one female Z. columbianus in each host. This pattern resembles that reported in other infected hydrophilids (Adamson et al., 1992). The broad North American distribution and multiple hosts make this species a potentially interesting subject for molecular comparison to determine whether possible cryptic species complexes may exist.Published as part of Carreno, Ramon A., 2018, Pinworms (Nematoda: Thelastomatoidea) from Insects Collected in Mississippi, USA, with description of a new species of Protrellus Cobb, 1920 from the Cockroach Ischnoptera deropeltiformis Brunner von Wattenwyl, 1865 (Blattaria: Ectobiidae), pp. 567-577 in Zootaxa 4531 (4) on page 573, DOI: 10.11646/zootaxa.4531.4.7, http://zenodo.org/record/261493

Xyo pseudohistrix Travassos & Kloss 1958

Xyo pseudohistrix Travassos & Kloss, 1958 (Hystrignathidae) Measurements. Females (n=2): Body length 3538 ± 265 (3350–3725); maximum width 155 ± 21(140–170); buccal cavity 9 ± 2 (8–10); oral annule length 13 ± 4 (10–15); oral annule width 34 ± 2 (33–35); esophagus 584 ± 30 (563–605); length of anterior corpus groove 65; corpus length 448 ± 25 (430–465); corpus maximum width 43 ± 11 (35–50); isthmus 50; bulb length 90 ± 11 (83–98); bulb width 75 ± 7 (70–80); vulva from anterior end 1968 ± 11 (1960–1975); vulva from posterior end 1570 ± 255 (1390–1750); tail 390 ± 57 (350–430); body width at tail 75 ± 7 (70–80); egg length 110 ± 8 (100–120); egg width 40 ± 4 (33–40); a = 23 ± 1 (22–24); b = 6 ± 1 (6–6.2); c = 9 ± 1 (9–10); V = 56 ± 4 (52–59). This species is distinguished from H. rigidus in having 32 longitudinal rows of spines rather than 16. Our measurements are consistent with the few data provided in a redescription of the species by Christie (1934). The species described by Christie was considered to be a synonym of Xyo histrix Cobb, 1898, the type species from Australia. However, Travassos & Kloss (1958) distinguished the North American species as separate from the Australian species. Xyo pseudohystrix was considered a species inquirenda by Hunt (1982) but retained in a more recent revision of the Hystrignathidae (Adamson & van Waerebeke, 1992b). It was not possible to further clarify the status of X. pseudohystrix in this study. Few records of this species exist, and its taxonomic status is in need of revision.Published as part of Carreno, Ramon A., 2018, Pinworms (Nematoda: Thelastomatoidea) from Insects Collected in Mississippi, USA, with description of a new species of Protrellus Cobb, 1920 from the Cockroach Ischnoptera deropeltiformis Brunner von Wattenwyl, 1865 (Blattaria: Ectobiidae), pp. 567-577 in Zootaxa 4531 (4) on page 574, DOI: 10.11646/zootaxa.4531.4.7, http://zenodo.org/record/261493

Hystrignathus rigidus Leidy 1850

<i>Hystrignathus rigidus</i> Leidy, 1850 (Thelastomatoidea: Hystrignathidae) <p>Measurements. Females (n=4): Body length 3800 ± 35 (3775–3850); maximum width 178 ± 5 (170–180); buccal cavity 8 ± 1 (8–10); oral annule length 10 ± 2 (9–13); oral annule width 32 ± 1 (30–33); excretory pore 985; esophagus 608 ± 25 (570–620); length of anterior corpus groove 70 ± 2 (68–71); corpus length 466 ± 16 (443–475); corpus maximum width 44 ± 3 (40–45); isthmus 59 ± 7 (50–65); bulb length 83 ± 4 (78–85); bulb width 82 ± 4 (80–88); vulva from anterior end 1933 ± 71 (1850–2005); vulva from posterior end 1868 ± 96 (1770–1950); tail 535 ± 18 (510–550); body width at tail 70 ± 9 (65–80); egg length 109 ± 5 (105–115); egg width 34 ± 3 (30–38); a = 21 ± 1(21–22); b = 6 ± 0.5(6–7); c = 7 ± 0.3 (7); V = 51 ± 2 (49–53).</p> <p> The specimens found here are consistent with descriptions of <i>H. rigidus</i> in having 16 spines per row on the cuticle of the anterior part of the body. The measurements provided here are consistent with those of Christie (1934), but are, for most characters, larger than those provided in a recent redescription (Morffe et al., 2015) but smaller than those provided in the original description of the species (Leidy, 1850). These inconsistencies in measurements also raise questions about the identity of the species described in various studies. Thus, a molecular analysis of specimens of <i>H. rigidus</i> from different localities could yield information on the possible existence of cryptic species.</p>Published as part of <i>Carreno, Ramon A., 2018, Pinworms (Nematoda: Thelastomatoidea) from Insects Collected in Mississippi, USA, with description of a new species of Protrellus Cobb, 1920 from the Cockroach Ischnoptera deropeltiformis Brunner von Wattenwyl, 1865 (Blattaria: Ectobiidae), pp. 567-577 in Zootaxa 4531 (4)</i> on page 574, DOI: 10.11646/zootaxa.4531.4.7, <a href="http://zenodo.org/record/2614935">http://zenodo.org/record/2614935</a&gt

Passalidae Leach 1815

Passalidae Two species of hystrignathid nematodes were recovered from 4 specimens of Odontotaenius disjunctus Illiger, 1800 (Coleoptera: Passalidae) (Table 1).Published as part of Carreno, Ramon A., 2018, Pinworms (Nematoda: Thelastomatoidea) from Insects Collected in Mississippi, USA, with description of a new species of Protrellus Cobb, 1920 from the Cockroach Ischnoptera deropeltiformis Brunner von Wattenwyl, 1865 (Blattaria: Ectobiidae), pp. 567-577 in Zootaxa 4531 (4) on page 574, DOI: 10.11646/zootaxa.4531.4.7, http://zenodo.org/record/261493

Protrellus browni Carreno 2018, n. sp.

Protrellus browni n. sp. Description (Figs. 1–3) Female (n = 21). Body robust, elongate, widest in mid-region. Body finely annulated, annules not prominent. Lateral alae absent. Oral annule with 8 looped labiopapillae (Fig. 1C, 2B). Amphids circular. Oral opening triradiate. Second annule not expanded, similar in dimensions to additional annules in head region. Esophageal corpus clavate; isthmus short, straight; basal bulb spherical with valvular apparatus (Fig. 1B). Nerve ring near mid-region of corpus. Excretory pore immediately anterior to vulvar opening. Vulva opening at start of lower third of corpus (Figs. 1A,B; 2A). Didelphic, opisthodelphic. Vagina and uteri posteriorly directed, ovaries extending to level of anus before reflexing anteriorly. Eggs large, consisting of a broad round end and gradually tapering toward opposite pole which is more pointed. Broader half of egg having a small curved region bearing small spines in first third; spines limited to this region (Fig. 3A). One side of egg slightly flattened in lateral view. Eggs lacking gold, green, or yellow coloration. Tail short, conical (Fig. 1A, D). Measurements in Table 2. Male (n=1). Small worms. Lateral alae absent (Fig. 1E). Head region slightly expanded. Esophagus with base of corpus slightly expanded, thin isthmus, and elongate bulb. Nerve ring near base of corpus. Testes containing amoeboid spermatozoa. Three pairs of caudal papillae present, including 1 pair subventral precloacal, 1 pair postcloacal adanal, and 1 pair in tail region. Tail subulate. Spicule present. Gubernaculum absent. Measurements inTable 2. are followed by range for female measurements.Published as part of Carreno, Ramon A., 2018, Pinworms (Nematoda: Thelastomatoidea) from Insects Collected in Mississippi, USA, with description of a new species of Protrellus Cobb, 1920 from the Cockroach Ischnoptera deropeltiformis Brunner von Wattenwyl, 1865 (Blattaria: Ectobiidae), pp. 567-577 in Zootaxa 4531 (4) on page 569, DOI: 10.11646/zootaxa.4531.4.7, http://zenodo.org/record/261493

Protrellus aurifluus Basir 1956

Protrellus aurifluus (Chitwood, 1932) Basir, 1956 (Thelastomatoidea: Protrelloididae) Females of this species were recovered from P. fulvescens in 2 localities (Table 1). Measurements (in micrometers). Female (N = 9): Body length 3403 ± 590 (2625–4300); maximum width 171 ± 30 (130–205); buccal cavity 12 ± 2 (10–15); oral annule length 7 ± 1 (6–8); oral annule width 25 ± 2 (23–28); second annule length 15 ± 2 (13–18); second annule width 40 ± 1 (38 – 41); nerve ring 101 ± 35 (70–143); excretory pore 138 ± 14 (125–170); esophagus 305 ± 25 (268 – 353); corpus length 233 ± 35 (194–308); corpus maximum width 35 ± 4 (30–43); isthmus 16 ± 4 (11–20); bulb length 66 ± 7 (50–73); bulb width 65 ± 6 (58 – 78); vulva from anterior end 178 ± 12 (165–198); vulva from posterior end 3397 ± 591 (2619–4296); tail 126 ± 29 (85–173); body width at tail 76 ± 12 (63 –88); egg length 82 ± 6 (73 – 96); egg width 40 ± 3 (35 – 45); a = 20 ± 2 (17–23); b = 11 ± 2 (9–15); c = 29 ± 10 (18–43); V = 5 ± 1 (4–6). Protrellus aurifluus was found in 2 localities (Noxubee and Plymouth Bluff) in P. fulvescens (Table 1). This host constitutes a new record. The type host for P. aurifluus is P. lata, from North Carolina and Maryland, and an additional report from P. uhleriana from North Carolina was previously reported (Chitwood, 1932; Hatcher, 1939). I have also recovered P. aurifluus from P. virginica in central Ohio (Carreno, unpublished results). Thus, P. aurifluus is not host specific in spite of its occurrence in only one Parcoblatta species in the current study. Measurements corresponded to those provided by Chitwood (1932).Published as part of Carreno, Ramon A., 2018, Pinworms (Nematoda: Thelastomatoidea) from Insects Collected in Mississippi, USA, with description of a new species of Protrellus Cobb, 1920 from the Cockroach Ischnoptera deropeltiformis Brunner von Wattenwyl, 1865 (Blattaria: Ectobiidae), pp. 567-577 in Zootaxa 4531 (4) on page 572, DOI: 10.11646/zootaxa.4531.4.7, http://zenodo.org/record/261493