SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '73e6c6c195d19d3b56e1b9d035cc701bee6478bc140695d6f9bd739dad2cc64c' 
  AND token = 'ZiKAiFHOQMP/hf81/CZu6SzLAqH4Q3Y9VA3nFQnTJ5g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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