SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '652c713ab775fea0758bc56af8a7caabee0dc7cc521fc43a952cde4eff7845c2' 
  AND token = 'bi8D2Vuk2BtPxH7ZVQhNLlEdMnMSlwPybXMF2WdMFRs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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