SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '82b3f58e1e266bef03726f99d67b08cc9acb863dcd225cf5b5268a2d420ad9e0' 
  AND token = 'l8Xx+nISSzMBQbtHrFj0OU7UI4ki1HhGoHycuHaHivI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00069

JSON explain

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