SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '56611a56823f46f39b8e546c4ff3b2b6eacd1389cb391f530e893c526620fb3e' 
  AND token = 'PVfkP85RwvYRI/ssrZKEOZJ+F8c9NhjwSuXIJ4BDxhg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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