SELECT 
  1 
FROM 
  q_lock_keys 
WHERE 
  key_id = '8cb3527dd391f99f437b309db0925c2bf2f7699965f8fd91b34aaa59afb7a1e5' 
  AND token = 'VNzaUBxpBfj8AoCSIF/fy29ctqkjMigs84vZtSuh+LY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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