SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1598cb1370a5d7a732174a77ba7588934bde91bef8d55a21cdd6d8fcd69123a2' 
  AND token = 'NUoqSMs1m4g1wguJdSazt84NQVpsXkKWjekf+lQKWfM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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