SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '700b3eac0ba1d8b27cfcf1541a2c736a23325ee11c9ddc84e0860469e6910095' 
  AND token = 'QTcRaJG3epZye52e2XiqNJq3JCfmWoHLDQhZbSX8Fro=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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