Spiders of North Carolina

Arachnids of North Carolina

Order:
Scientific Name: Common Name:		Family (Alpha):

Leiobunum hoffmani - No Common Name Sclerosomatidae Members:			NC Records	BugGuide Account	Public View

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Distribution Records
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Vetting Levels

Adult phenology:
High Mountains (HM) ≥ 4,000 ft.
Low Mountains (LM) < 4,000 ft.
Piedmont (Pd)
Coastal Plain (CP)

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synonym

taxonomic_comments

Approximately 30 species in this genus have been identified as occurring in North America north of Mexico (Cokendolpher and Lee, 1993; Ingianni et al., 2011), with 16 recorded in North Carolina. However, the validity of several of these species is suspect, with several that will probably be determined to be synonyms of other species, e.g., davisi, speciosum, and zimmermani in North Carolina Burns et al., 2012; Shultz, 2018). According to Shultz (2018), moreover, recent phylogenetic studies indicate both that more species are waiting to be described and that the name Leiobunum may eventually be restricted to European species, requiring new generic names for most, if not all, of our species.

species_comment

Belongs to the Leiobunum Calcar Species Group as described by Ingianni et al. (2011), based on both male and female reproductive structures; further confirmed by genetic analysis (Burns et al., 2012). Other North Carolina species in this group include nigropalpi, euserratipalpe, and calcar.

id_comments

The dorsal surface of the males is typically light orange brown, similar to the males of calcar (Ingianni et al., 2011). The ocularium is dark brown and the abdominal tergites are marked by rows of light spots; the central figure is usually absent. In some males, however, a well-developed central figure is present and the dorsum is highly patterned with dark and white patches. Coxae, trochanters, and femurs of the legs are all golden brown. The chelicerae and palps are mainly dark brown.

total_length

6.5 mm, male holotype; 7.6 mm, female paratype (Ingianni et al., 2011)

structural_features

The palps of the males are conspicuously inflated and usually have a large, retrolaterally projecting cone on the femur, similar to that of male calcar (missing in some individuals). The abdomen is pointed posteriorly in the males, again similarly to calcar. In the northwest corner of North Carolina, where these two species overlap, identification of both males and females requires microscopic examination of the reproductive structures and other key characters. Females in general are best identified by their reproductive structures (see key in Ingianni et al.).

silk_web

fld_guide_descriptions

online_photos

prey

predators

behavior

distribution_reference

Ingianni et al. (2011)

technical_reference

Ingianni et al. (2011)

adult_id

1 identifiable by photo 2 identifiable by photo of specific features and/or supplementary info 3 identifiable from specimen only

abundance

Hoffmani was commonly observed at bait at one site in Ashe County. However, we currently have too few records from North Carolina to accurately judge its frequency of occurrence or abundance.

distribution_comments

So far known only from the extreme northwestern corner of the state

checklist_mt_high
>=4,000 ft.

Regular	Frequent	Infrequent	Occasional	Seldom	Frequency Regular – almost always observed on given visit; >=90% chance of observation Frequent – usually observed on a given visit; >=50%<90% chance of observation Infrequent – observed less than 50% of visits; >=25%<50% chance of observation Occasional – observed on only on a small minority of visits; >=10%<25% chance of observation Seldom – not usually seen on visits; <10% chance of observation These terms refer to visits to appropriate habitats made at appropriate times of the year, making use of common sampling/observation methods. Under those conditions, Frequency refers to the chance of observing at least one individual on a given visit made anywhere within a particular region, or over multiple visits to a single site.

checklist_mt_low
<4,000 ft.

Regular	Frequent	Infrequent	Occasional	Seldom

checklist_pd
Piedmont

Regular	Frequent	Infrequent	Occasional	Seldom

checklist_cp
Coastal Plain

Regular	Frequent	Infrequent	Occasional	Seldom

habitat

Many of the records from Virginia come from the Spruce-fir zone at the summit of the highest peaks in that state (Ingianni et al., 2011). The two North Carolina records, however, come from relatively low elevations, 3,600' for one site and about 2,200' at the other. At the Ashe County location, the species was observed along a ridge top with an extensive stand of relatively mature cove hardwoods located on the north-facing slope.

observation_methods

This species appears to come well to beer-banana bait painted on trees. It appears to be most active at night, but has also been found during the day on the outside of an out-building.

state_protection

Arachnids are not protected under state law, although permits are needed to collect them in State Parks and other public and private nature preserves

NHP_ranks

GNR [S2S3]

NHP_status

[W3]

status_comments

The global rank of this species has not yet been determined, but it currently appears to occupy a very small range in the southern Blue Ridge. Hoffmani has so far been recorded from only two sites in North Carolina and there is much to be learned about its habitat associations, distribution, abundance and population trends.

Photo Gallery for Leiobunum hoffmani No common name
	Recorded by: Steve Hall Ashe Co. Comment: Male; found on outside of a well-house. Appears to be the variant of hoffmani that lacks the retro-lateral projection on the palpal femur		Recorded by: Steve Hall Ashe Co. Comment: Male; found on outside of a well-house. Appears to be the variant of hoffmani that lacks the retro-lateral projection on the palpal femur

Photo Gallery for Leiobunum hoffmani No common name