SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ed27f578bd348223c86f8451ea32ca41255040896f0a2d15cfea50b0a0ea019f' 
  AND token = 'M2AlX783mZZ3fKsvuXgfMfuo5e/X5b9qQLXU0/pliRA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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