SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '99045cdc22de2fb6d49971f1bbc24870cc94773ca78f7698763b0dd56e6aa3da' 
  AND token = 'JO5SEVt8l7VJqcKNNpWgD/HOJn90iLBQLFnKAXzzI+M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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