SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7df89d84e5aee747c783a98ea5b133545352925b6954c4620afa8894fa0ebcf6' 
  AND token = 'CKxGIrKwExRSsh2iHqFrSg4+gXShy3jLQRQLSLg1fRc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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