SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1f3bd20ec9c3c3da71245c8c7cfe478176cae25518819e9c80efcc120b5e0362' 
  AND token = 'ZGgwRKqRnTa05V9F7ojFLXuP7Sz0Eb6KCO3N/kwqgr4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00010

JSON explain

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