SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4b1adb849b0948f878669fb6ce00219dbd3bc1b06ce5041e9e120270b9c258ae' 
  AND token = 'jULB0v2wXz+JYx62oP3omOz5ipGPoqBllllGx/vDjB0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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