SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9a52b8a7fe74e3a7912c45ade27babad4f49ab12a1c8785ca25aa73803fbef2b' 
  AND token = 'oEmYuu3UXOMrCHASClo4iBcLaQ5dh8i7O4bQgaCgaMw=' 
  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"
    }
  }
}