SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c176af917a39f1df2951849bfd1ec1477b8c847293ad3ab347d663505187fcbd' 
  AND token = 'KjxMazA4TgqorsrggOZD++a6wzcfQ6WQuVTez2fLH9o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}