SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '1d23b569bb741a34008a8b4ae0825c5ffdc096d665fdc67af4062e2021054a85' 
  AND token = 'lLClvfmglEMYHa3tISme8FJt1JFr7iNNZTW69iI8Pkg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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