SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eede190d9af99223745212b57f97890adbfa02e79f1cf94d00aa1037f4527349' 
  AND token = 'QZ5b6LHmjORQ9kIIWTcsC05/M8/Q1rhaWkI9lhSX9qw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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