SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '19d647eb553c5f676a71ddfda289c538ce45ad87a658c1f9b138a20aa3656ab0' 
  AND token = 'gtugfJqKzuReIyFfUBX8IGqcDiQIGZYGHBRZH2BfvSc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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