SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ea9518b01f3f67f704e8b1cd61f91d8dfe2e3fad13b7941fc5b41937a433f554' 
  AND token = '9mb7kynNjabQVD8Z0echOhOkE3edMDRkpNQhPMfVVyE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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