SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '28e5eed776627be77e826f6c9f7d8d0f310869597041963fcf2cfcab66c41735' 
  AND token = 'VOr5O4XKWNvhQg2IBVm6relFejLHOJgTo2JX/Op1Bv0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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