SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '887c59fa442451dfc3d38af98ff424d14f673e380fa9be42ba9003bbee25225d' 
  AND token = 'UP2acUHPFa6jBXDBJph2YTYfKlLl+pTyKjDlyKyWpBI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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