SELECT 
  1 
FROM 
  q_lock_keys 
WHERE 
  key_id = '3f49eaf81c6fd30a6b922e7875c530eefa61f3cab09d634284cc0bc3bd56d433' 
  AND token = 'BV7ohVgRMUXnLg6fZ2XobjuYiwaMoRuGaPdyjuXiIls=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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