SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '19c79b06ea6234254c2d43c6f178c30034b11622778f2e34c33f677e42dbdeb7' 
  AND token = 'avKFhOj/+/hF1uv8VdJDumOTkV0ipNh89UedHwZ8wCU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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