Arctiostrotus fontinalis

## Source: ResearchGate

INTRODUCTION

Very few earthworm records have been reported from

the Yukon Territory of Northern Canada. Berman and

Marusik (1994) reported Bimastos parvus and

Dendrodrilus rubidus from two locations in southwestern

Yukon:

1. East bank of Kluane Lake, Christmas Bay, Christmas Creek

mouth of the valley (in the site of ground road transpassing),

approximate coordinates 61°03 'N, 138°21 'W, 22 July 1993,

moist site of flood plain covered by water from time to time after

strong rains. Worms were taken from the first soil centimetre

directly under thin crust of young moss. Many earthworms and

their cocoons. It should be added here that close to this locality,

on the widely spread Sheep Mt. Range in the Cultus Bay

Drainage Basin on Kluane Lake, in the hollow on the north part

of the watershed (ca. 1200 m above sea level) in the willow

grove with moss cover, big enchytraeids (up to 4-5 cm) have

been found (13 July 1993), as well as smaller worms at the

elevation of about 1500 m in the willow grove litter.

2. Carmacks environs, about 10 km to the west from the main

road, near an unnamed lake from the right of ground road

(approximate coordinates 62°11 'N, 136°22'W, 19 July 1993).

About 30 worms . . . and their egg cocoons were collected

directly along the shoreline, 10-50 cm from water edge in the

one-cm horizon of the soils. No doubt, such a peculiar

supralittoral belt can flood during rough weather.

Teale (2007) conducted field collections during

June-August 2005:

[T]o substantiate anecdotal reports and obtain habitat

information. Sites were sampled by hand-sorting the soil from

25cm by 50cm plots or multiple small excavations in a localized

area, and extended through the organic layer to the mineral layer.

Sites were concentrated in limicolous (muddy) and garden soils

as suggested by anecdotal reports as well as Berman and Marusik

(1994). Others were taken along roads and waterways to

investigate the possibility of those corridors acting as dispersal

routes (Dymond et al., 1997; Tuinov et al., 2006).

In her preliminary survey, she recorded

Aporrectodea tuberculata, Dendrobaena octaedra, Eisenia

foetida, Lumbricus rubellus and Lumbricus terrestris

primarily in the greater Whitehorse area (Teale, 2007). A

summary of the species first reported from the Yukon

including their ecological type can be found in Reynolds

(2018).

There are other terrestrial oligochaetes reported

from the Yukon, notably a species of Enchytraeidae

(known as pot-worms) which are small white worms found

in soil and aquatic habitats. These were first reported from

the Yukon by Smith et al. (1990). Some of these were later

described by Tynen et al. (1991) as a new species to

science as Henlea yukonensis. Currently, they have

only been reported from the Beringia Refugium.

This paper reports the first collection of the

native North American species, Arctiostrotus

fontinalis McKey-Fender, 1994, from Canada. There

have been reports of other species of Arctiostrotus in

Canada, in particular, British Columbia, e.g.,

Arctiostrotus perrieri (Benham, 1892) on Queen

Charlotte Islands (Haida Gwaii), Vancouver Island,

Neave's Island, Granite Island, Amos Island, Hohoae

Isla nd, Kamil's Island; and Arctio strot us

vancouverensis McKey-Fender, 1994 on Vancouver

Island. A closely related species to this genus is

Toutellus oregonensis (Smith, 1937) which has also

been reported from Vancouver Island (McKey-

Fender et al., 1994).

RESULTS

Benoit Godin and Denise Horwood

collected Arctiostrotus fontinalis (0-0-1) from

Surfbird Hill (Tombstone Territorial Park) 64.6977N,

138.4365 W at 1164 metres elevation, under willow

(Salix sp.) litter on 30 June 2018 (Fig. 1). The site is

near the bottom of the slope, on the east side of the

pad of the microwave tower to the west of the

Dempster Highway. (Figs. 2, 4, 5). It is located in a

dwarf birch (Betula sp.) and willow area of the

alpine/subalpine habitat. The soil was a wet black

organic soil (Organic Cryosol) (McKenna, in litt.,

15/11/18). The soil and litter samples were collected

using a garden tool and a dust pan to remove swiftly

the leaf litter and underlying soil containing the

organisms. The litter was then sifted through ¼ inch

(6.35 mm) nylon mesh. The residue was observed

for several minutes to check for the movements of

small organisms. The specimens were preserved in

70% alcohol and then sorted and preserved in 90%

alcohol for identification.

The characteristics of this small adult

clitellate specimen: 67 segments, clitellum on

segments 12, 13-18, no tuberculata, genital markings

in 12/13, male porophores, flat round, 1.5–2 times

AB, prostomium tanylobic, broad (Fig. 2), setae

separate, dd interval nearly 50%, aa:ab:bc:cd:dd =

2.2:1.0:1.6:1.6:9.8, dd:U about 0.48. For an

explanation of taxonomic characters and conventions

used in earthworm taxonomy consult Reynolds

(1977) or Gates and Reynolds (2017).

DISCUSSION

According to McKey-Fender et al. (1994),

Arctiostrotus fontinalis is the smallest and most

frequently found of the known Arctiostrotus species.

Originally collected from Tillamook County in

Oregon, USA in a seepage area on a spruce-hemlock

forest slope, it was also collected from saturated soils

in the same location in soils with a pH of 4.0 (H2O).

This species has also been collected in similar

habitats in Pacific County in the state of Washington,

USA in silty soils with a pH of 4.5 (H2O). A few of

the original collections of this species were from

terrestrial sites, but most were found in seepage

areas, at the margins of springs or near springs in

saturated little layers and/or saturated mineral soil

(McKey-Fender et al., 1994). They share the habitat

with other native megascolecid species, such as A.

perrieri (Benham, 1892), Driloleirus michaelseni

(Smith, 1937), and Kincaidodrilus kincaidii (Altman,

1936).

The American sites were at low elevations,

i.e., less than 100 metres, while here in the Yukon the

specimen was collected at 1164 metres elevation.

The American sites were also in spruce-hemlock

(Picea-Tsuga) conifer forests, while in the Yukon it

was found in willow (Salix) litter.

Recording one or a few specimens of a new

introduction of an earthworm species in North

America is not unusual (see Table 1).

So the fact that only one specimen of

Arctiostrotus fontinalis was collected in the Yukon

Territory at this time, is not unusual. Earthworm

collecting in the Yukon has been limited and

additional sampling in the future may possibly

uncover more specimens of this species and other

closely related native and introduced European

species.

First earthworm record of Arctiostrotus fontinalis in Canada20

Table 1. Some first introductions of earthworms in North America where only a few specimens were obtained.

Species Location Number No. Counties Reference

Specimens where present

Allolobophoridella eiseni Alaska, USA 0-0-5 1 Reynolds (1977, 2018)

Amynthas carnosus Kansas, USA 0-0-5 1 Carrera-Martínez & Snyder (2016)

Aporrectodea icterica Ontario, Canada 0-0-1 1 Reynolds (1976)

Arctiostrotus adunatus Washington, USA 0-0-1 1 McKey-Fender et al. (1994)

Arctiostrotus johnsoni Washington, USA 0-0-7 1 McKey-Fender et al. (1994)

Bimastos lawrenceae British Columbia, Canada 0-0-5 1 McKey-Fender et al. (1994)

Dendrobaena attemsi Oregon, USA 0-0-1 1 Fender (1985)

Dendrobaena lusitana New Brunswick, Canada 0-0-1 1 Reynolds (2017)

Dendrobaena pygmaea California, USA 0-0-1 1 Fender (1985)

Dichogaster modigianii Florida, USA 0-0-1 1 Csuzdi (1997)

Eisenia andrei California, USA 0-0-1 1 Fender (1985)

Eisenia hortensis Arkansas, USA 0-0-1 1 Causey (1952)

Eisenia zebra California, USA 0-0-1 1 Michaelsen (1901/2)

Helodrilus occulatus Virginia, USA 0-0-15 1 Callaham et al. (2016)

Lumbricus friendi Maryland, USA 6 sites 3 (Csuzdi and Szlávecz, 2003)

Lumbricus meliboeus New York, USA 0-0-5 1 Rodríguez et al. (2012)

Murchieona muldali 1Michigan, USA many 1 Murchie (1954)

Satchellius mammalis New Jersey, USA 0-0-4 1 Davies (1954)

1 recorded as Allolobophora minima.

ACKNOWLEDGEMENTS

We are grateful to Wilma M. Reynolds of the

Oligochaetology Laboratory for reviewing the

manuscript, their comments and suggestions. We

acknowledge Bruce Bennett of the Yukon Conservation

Data Centre, Whitehorse for forwarding the specimen

fo r de t ermina t i o n , a n d K a r e n M c Kenna ,

CryoGeographic Consulting, for information on soil

type at the collection site and earthworm records in the

Yukon. The senior author appreciates Dr. Erin

Cameron, University of Helsinki, for suggesting the

specimen be sent to us. The authors also wish to thank

Dr. Catalina C. de Mischis, Universidad Nacional de

Córdoba (Argentina), Dr. Jean-Marc Gagnon, Canadian

Museum of Nature, and Dr. Josef H. Görres, University

of Vermont for translations of the abstracts and key
words