SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4745ddcf859b4ad180d751cab9fb57fa9a97125c836109926ec1e65cac7a00a8' 
  AND token = 'AS+dYNb26evZ4SVSMrUwmNJECQ5xb7WA4eyqiE43hbU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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