SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3329e080199c277a1dd4265a9ffe31706694c0373b87fc805c06c18859fc932f' 
  AND token = '7KzS5hF4uZgrfLxMTVNiZRuB2u6rDw1gJAWS0AoN3XU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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