SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fb0c09a6266c50002c035ac032f2b5942668216fb9065e1a80d33d9f7c06b0be' 
  AND token = 'TrHqZq/GEacvALzX2idxt3zOatdwdXAueNZqDkFkePg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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