SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '64bdcc5c215d2c6af9e905bf22385e6049957ab85bfd0f7dfa8c9d713eba33e6' 
  AND token = 'ssYAtaXRELTvqvCp9FrXPGmwyTAEuLHmVeq/kFM6cgU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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