SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '512cc393686a5e427a6b006eccf3167614f9680b4662150cefa1125bcfa49e69' 
  AND token = 'w7Ml2tdsKbCsZ3uiNcCNUSiQhseNb4bWTRVSFwzBdtc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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