SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '587e9938eab3fe738a72741086f567d41e8b9c8498349f404ac4826a6c18648f' 
  AND token = 'V8dpjkkpOXhrP+aTofi9NumWlyJA4JZIWuU8/44TsHU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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