SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '241ad4727e61fa60bdbb1845206ae8eea5ffa976ae50dcbbdf02606662b82a0f' 
  AND token = 'oMrsaEmmea5L9EILHdZTwIOCg2HjKAaVxtR6bvdHEM0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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