SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ae67da108783a9cb79e353e71724f5cb3a6f526c49a201be4b62ed1696f175e5' 
  AND token = '8M9X8sFNFnquVQr1hVSMle3wKpu1ukwXM9gtpULBPpo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00060

JSON explain

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