SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ddc70bda40c45ab9edbabcf46e76736fefa8c07b8a6f626c0b313d52bbcd3de9' 
  AND token = 'qh7Ief65zRJmeIUr7cjYRjAhHsySBNQKihkKIilEF+A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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