SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e8fbbbc4cebd847b8d33c891aabab830b96215f398044187f9141b361e546237' 
  AND token = '0ZeEY0qNMnvFwrFVjoZdV43e5cylu5CfuchIvcd9wNs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}