SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9d706ad6861a4c38100c886e1c0c87ca81de1f5736e842c7fb54bd79e93849b8' 
  AND token = '22IejbGwB/Sjjp2sntu4OzJcjpmqtlDtvAyTz6bxxFw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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