SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd159465ae08bab3e6a065580178bddddbd47df28439d07184741e02aa3f5e1ce' 
  AND token = 'a1FnzyHlbWD8NTtGvkox8WFJHFImRCbSHT6fXIea7Rc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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