SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5ce0d66072c139e2abfec09751f6ebc0fedd925c330c3016ee5243ee436ce8a9' 
  AND token = 'cOW0eY7KrvhiEOVOzrOm5brz1TqnJL6L9mGQncTIxRk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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