SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5adbfd06167118d388489ed680f7b835596f25a2b1ae262cb4a68f5b2b847f6d' 
  AND token = '9DH/wJvhcxcaCxzNjdQquZY9X9yPnpPTkNlK3WiS+G0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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