SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '517b5bd5c2028365b371003c80e128981f0e5724b7af279a418e48c4e2eaf44d' 
  AND token = 'STbQ5a8GYdSukdMrmQ9DvbgEQRG9owmqG6L/l1wSiZ0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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