SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '1c7054f93a8c00cb77ed25edc1e0869e295fb2968143ce7706052861fa42d154' 
  AND token = 'GeLgZFrITUYbAWkyOHJ+Uz5SogSerizJj75J9RJgV/s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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