SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ebfe6306ed7987d5017dd77ca87be5486d67b431e0082dfa385beb6b9b614fea' 
  AND token = 'DvUjNCa3XTAbn5T6EQtTuVyz7xxpnSb7t+Xp2G336k0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00061

JSON explain

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