Hitobia sp. ESPLANADE
Genus Overview: Hitobia
- Hitobia is a genus within the family Gnaphosidae (ground spiders), known for their nocturnal habits and ground-dwelling behavior.
- Gnaphosid spiders are characterized by:
- Cylindrical anterior spinnerets
- Eight eyes arranged in two rows
- Flattened bodies adapted to terrestrial habitats
- Hitobia species are predominantly distributed in Asia, especially in China, Japan, Korea, Southeast Asia, and parts of the Indian subcontinent.
Comparison with Known Hitobia Species
- This new record of Hitobia sp. ESPLANADE shows a body length of 5.5 mm, aligning with the typical size range of Hitobia species (3-6 mm).
- Notable features:
- Dark oval abdomen with subtle patterning
- Relatively elongated legs with banding
- Compared to species like Hitobia unifascigera and Hitobia
procula, this new species has:
- A darker, more uniform dorsal abdomen
- Fewer contrasting markings
- A distinctly narrow cephalothorax
Phylogenetic Relationships
- While definitive phylogenetic placement requires genetic data (e.g., COI gene sequences), morphological traits suggest this species aligns closely with a subgroup of Hitobia that exhibit cryptic coloration and small size—traits that are useful for camouflage in forest floor habitats.
Morphological Description
Size
- 5.5 mm total body length (as indicated on image)
Coloration
- Dorsal View:
- Cephalothorax: Light brown with a shiny, metallic sheen
- Abdomen: Dark grey to black, possibly with faint speckling or setae
- Ventral View:
- Legs: Pale with darker joints and segment bands
- Abdomen: Pale central band with darker lateral areas
Eye Arrangement
- Typical Gnaphosidae eye pattern:
- Two rows of eyes (anterior row slightly procurved, posterior row straight or slightly recurved)
- Relatively small and closely spaced
Leg Structure
- Long, slender legs with banded appearance
- Adapted for rapid ground movement
- Leg formula and spination would help with more precise ID (not visible here)
Spinnerets
- Cylindrical anterior spinnerets visible in the ventral view—typical of ground spiders
- Posterior spinnerets not clearly visible but likely follow the pattern of short, segmented structures
Unique Traits
- Uniform dark abdomen and metallic cephalothorax may distinguish it from more mottled or banded Hitobia species
- Lack of distinct dorsal patterning (e.g., chevrons or stripes) may indicate a separate species
Ecological and Behavioral Insights
Habitat Preferences
- Found at River Esplanade (semi-urban riverbank environment) of Bandar Sri Indah, Tawau, Sabah
- Likely inhabits leaf litter, under rocks, or grassy edges—common microhabitats for Hitobia species
Hunting Strategies
- Hitobia spiders are active nocturnal hunters
- Do not spin prey-catching webs
- Hunt small arthropods on the ground using stealth and speed
Web-Building Behavior
- Generally non-web-building for prey capture
- May construct silken retreats under stones or bark for resting or molting
- Silk is used primarily for egg sacs and shelter, not hunting
Interactions
- A solitary species
- Avoids interactions except during mating
- Plays a role in controlling small insect populations
This unidentified male spider from the Hitobia genus, collected from the River Esplanade of Bandar Sri Indah in Sabah, shows morphological traits typical of Gnaphosidae but may differ from described Hitobia species by its:
- Dark, relatively uniform dorsal pattern
- Small body size
- Slightly metallic cephalothorax
Further taxonomic work—including genital dissection and DNA barcoding—would be essential to determine whether it represents a new species or a variation of an existing one.
Here is a comparison table to document the morphological traits of the unidentified Hitobia sp. ESPLANADE alongside a few known Hitobia species. This table highlights distinguishing characteristics useful for preliminary taxonomic assessment:
Comparative Morphological Traits of Hitobia Species
| Trait / Species | Hitobia sp. Esplanade | Hitobia procula | Hitobia makotoi |
|---|---|---|---|
| Body Length (♂) | 5.5 mm | 4.5-6.0 mm | 4.5-5.5 mm |
| Thorax Color | Pale brown, metallic | Reddish brown with dark pattern | Pale yellowish brown |
| Abdomen (Dorsal) | Dark grey to black, uniform | Paired chevrons or bands | Patterned with dark spots |
| Abdomen (Ventral) | Pale center, dark lateral sides | Mottled dark brown | Speckled or banded |
| Leg Coloration | Pale with dark banding | Pale brown with slight banding | Yellowish with dark annulations |
| Spinnerets (Anterior) | Cylindrical, prominent | Cylindrical, dark-tipped | Cylindrical, pale |
| Eye Pattern (General) | Typical Gnaphosid (8 eyes in 2 rows) | Same | Same |
| Dorsal Patterning | Lacking distinct markings | Present (chevrons) | Present (dots or patches) |
| Habitat (Typical) | Riverside esplanade, leaf litter | Forest margins, under stones | Grasslands, shrubby areas |
| Known Range | Sabah (Malaysia, Borneo) | China, Korea | Japan |
Notes:
- This Hitobia sp. ESPLANADE 's dark, uniform abdomen, metallic cephalothorax, and lack of dorsal markings differentiate it from the commonly described Hitobia species.
- Leg banding and the overall coloration may indicate adaptation to shaded ground microhabitats like leaf litter near rivers.
- The presence of cylindrical anterior spinnerets, typical of Gnaphosidae, confirms its placement within the genus, but genitalic examination is essential for accurate identification.
- A molecular barcoding (COI) analysis is needed to assess whether this is a new or cryptic species within the genus. (Note: We keep images, we do not keep specimen.)