SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '01efa81937474d0e5c7af3a80b331eb73766a7f30f93b71377f565bcf402646d' 
  AND token = '/sRKwB+ZlvYpq+iCyVmMoaO5odGhrZvhCYrD5NEERnk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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