SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6c802744a0f64d87edd4087d6e122ad5b50b24d55c93e3637cddf3d2057004ae' 
  AND token = 'plOdhZxK0TwHXGIaTvmZtqOXMGjDai610LK+g9O9gEQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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