SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ad35e45a9dbe3b585d125349573af8679d933111d19d169f8629a1a972d2bc65' 
  AND token = 'q2PXlq+4lG3FRPGnLSVIDHJux6nuSj/gNZlSV1uY5Vk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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