SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4ef5f8ce5e26ccdd22b9d9a44ad876606924a25b07856fbd3256180dd7c2abd4' 
  AND token = 'zqwctNBhbmthu++WTpTCKzrfgiKD3nRp4ErGoyh5ruE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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