SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c5ea3e66bfe93b3981e75c66f1ef5a9dd7619862beac79b2cc0aa93d24990078' 
  AND token = 'VRjHmEOJdrsAETaLSUYyYOVuy4ZJRORa/ZXBWWJa35c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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