New guinea sugarcane weevil - Rhabdoscelus obscurus
Effective: April 2, 2013
Taxonomic Position: Coleoptera : Curculionidae
Pest Type: Insects
Pest Code (NAPIS): INASDHA
This pest is a member of the following surveys: Palm
These Approved Methods are appropriate for: 2025, 2024, 2023, 2022, 2021, 2020, 2019, 2018, 2017, 2016, 2015, 2014
Pest Information
CAPS Pest Datasheet: https://download.ceris.purdue.edu/file/3061
Pest Tracker: https://pesttracker.org/pest/INASDHA
Hosts Identified in the CAPS Host Matrix:
Sugarcane
Human and Animal Pathogens Transmitted:
Not known to transmit any human or animal pathogens.
Pest Pathogens and Organisms Vectored:
Not known to vector any pathogens or other associated organisms but damage may lead to invasion by secondary pests.
Survey

Approved Method(s)
Method Detail NAPIS Survey Method
Trap 26 - Palm Weevil Bucket Trap 3001 - General Trapping Procedure
Trap 23 - Homemade 5-Gallon Bucket Trap 3001 - General Trapping Procedure
Visual See the CPHST pest datasheet for detailed survey instructions. 3031 - General Visual Observation
Method Notes:
Visual surveys may be used to detect larval populations before adults emerge. A trap and lure combination may be used to detect adult populations. See the CPHST Pest Datasheet for survey instructions. See USDA (2010) for instructions on making a Home-made 5 gallon bucket trap.

Approved Lure(s)
NAPIS Code Product Dispenser Effectiveness Compound(s)
107 Rhabdoscelus obscurus Aggregation Lure polysleeve 42 days 2-methyl-4-octanol
Palm Weevil Lure, Ethyl Acetate polysleeve 42 days ethyl acetate
Food bait (Rhabdoscelus obscurus) N/A 7 days split sugarcane
Lure Notes:
Do not include lures for other palm pests in the same trap when trapping for R. obscurus.

Survey Recommendations
The following are recommendations for executing the survey using the approved methods for pest surveillance. The recommendations are developed through literature review and consultation with subject matter experts.
Key Diagnostic or Identification

Approved Method(s)
ID/Diagnostic:
Morphological. The genus Rhabdoscelus can be identified through morphological characteristics. Key characteristics include: mesocoxae separated by more than the width of a mesocoxa, spotted or blotched elytra, pile raised in irregular vittae and pustules, and moderately large elytral strial punctures (Zimmerman, 1993).

Brodel (2013a) provides important morphological characters of Dryophthoridae, showing how to differentiate this family from Curculionidae.

A Dryophthoridae key by Zimmerman (1968) as modified by C. F. Brodel (2013) is found in Brodel (2013b).

A key to domestic and PPQ-intercepted genera of Dryophthorinae can be found in Brodel (2002). This key includes several genera of importance, including Metamasius, Rhabdoscelus, and Rhynchophorus.
Mistaken Identities:
Rhabdoscelus obscurus resembles in shape, size, and coloration other sugarcane- and palm-attacking dryophthorid weevils distributed throughout the Americas and Southeast Asia. See the CPHST Pest Datasheet for a detailed list.

References
  1. Brodel, C.F. 2002. A key to domestic and PPQ-intercepted genera of Dryophthorinae (Coleoptera: Curculionidae). USDA-APHIS-PPQ, Miami, FL. 6 pp.
  2. Brodel, C.F. 2013a. Important morphological characters of Dryophthoridae. USDA-APHIS-PPQ. 1 p.
  3. Brodel, C.F. 2013b. Dryophthoridae key by Zimmerman (1968) as Modified by C. F. Brodel (2013).
  4. USDA-APHIS-PPQ-EDP. 2010. New Pest Response Guidelines: Red Palm Weevil, Rhynchophorus ferrugineus.Riverdale, Maryland.

If you are unable to find a reference, contact STCAPS@usda.gov. See the CAPS Pest Datasheet for all references.