SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '45c6e477cbe07a69d7b1537dde6f6633965f4b886ae6af22d820ec91af05004d' 
  AND token = 'HCR9R2ahcX8NDML8mjYqKkjjAASxyG/cyI534a4sLeA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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