SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '792163b89c5555408944c75e01de2066b2e2c422157fc8b91bdb6cb887e69829' 
  AND token = 'IZVYMIlfB7XBhyggqxCw4QKp+xoM9Q9WwmgyFM4+V9U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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