SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '37ad070ac2675e97d1fc1e8f449bf51fa789ad67e9a517dae5942a8acdcd3f27' 
  AND token = 'ruruLgIuV42C4ngrlSiGgsLdOCETeKUqVW0rqBiqbIg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}