SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f4494a63ede0925da8724c3179074f99ccf7994d997abe3d7ead0405ca7b07af' 
  AND token = 'Hvoqp4VkJXYnGpBXdA0xx5RC71TSRxLj7DHrdnjsT1Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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