SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2bbb1176ebbb9673d2c304fafc72064c77ab72be99c9b7a12a77ac110e1696a1' 
  AND token = '7swJdb+pbWCijPHKJIPlRdzaPmaXErX2BG01llZ8918=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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