SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '33caa4d3e45db166bd729dedfab560799981ef23215bae4dffed5d38dc19b3d7' 
  AND token = 'OVcJtVoZVs4mx9K01dYlAENODz2otoXOuiuZQh6pvb8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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