SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd123928d89c6f52b400e67982cfc8293084153cea3c932dca56afdb2dbf4dfc4' 
  AND token = 'pE9x7dGIsbtfg/bLFzPWQ6Pchx3SFmkOkHDJQhGuVmE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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