SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f164a88c4bb441970fdeb28ed3896591177ac21027541d05912f1120fc85a31e' 
  AND token = 'pt/bWZcP8QpKV4LBVn8vqJyebExavp69fgdQ9BbMZIE=' 
  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"
    }
  }
}