SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3d987ecd419b1d85f59093547eaf09ad36dec7498d0b211e19875a68c22cc438' 
  AND token = '9JlGN9ZShPrzZbjo1GojXIRzlRKtJ78Vzm2W+5h8JTE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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