SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7a8ff5d300b8a5aa0981ef693ba0589c3cc05fa3e76a123b97fb6da10bdf33e9' 
  AND token = 'D7P3Zk6VtsU5gcrqtNT03xZplECPpOhRHXYYhec9op4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00053

JSON explain

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