SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cddc8317e92b2bcb160ef96204ac93192c5d70c2ff2623a656b00dc4bdc6f069' 
  AND token = 'SM8qRJcDToA9AOf+UnluitKuBepzY9uMt7PJc1otB7k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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