SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '01cd53b0c9c23ccb0db12b6d5e03d083298b3072ec373661167006cac540b431' 
  AND token = '3/mJ15+vZMFcihS8Ku1QrQ8Z1TKQWu7F0BAkmK/Lqts=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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