SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '410d515df28ca317a93bb23de52d8ef57c9ae028ffa391845055c391640e372e' 
  AND token = 'HXTj+xRjqS4IfWRnvd9IKyoxej1FmQlhgJ4OtQqnDlM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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