SELECT 
  1 
FROM 
  q_lock_keys 
WHERE 
  key_id = '643a826f22a3e9b062abcd63470f4381ae5c9784ac9de53b4f588f5b5a48b808' 
  AND token = 'xuEdDwjqjyRwOY8YOghqszklXQ6EV2JUjsq+vSOeJZM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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