SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1d231e3ac2539a9d364c3212b5fdd3cfa13fd5c59c8e3ffa93b7e0804e440569' 
  AND token = 'L/Dn1qSGalugbpZYxvbwgpwdEfmt20OZa+a+24muZeI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}