SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ba0b57cc7f9961f98a7926678a62a2400e2e7af7bd9bfef627d923bf064c82ca' 
  AND token = '5Em2lpvQOoXLjMUjaSwDlR+Y654S+1Djm/hrVZA3uFU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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