SELECT 
  1 
FROM 
  q_lock_keys 
WHERE 
  key_id = 'ff68c034dbaffac65482fa5f0eaaaed9c8070fe1ea18b38098ccc3ff5c48de3d' 
  AND token = 'nQdVwcuGQqtGzhVDzO21huCWisgd5pybAfjvsL6dx8s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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