SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e2fe59bd3231517fb2458e360b28a01ee700e5d975b99558bb7dace554359978' 
  AND token = 'mQ8k8964ys3WPh07YQjnJUMyQ/VCRa+LsrR6hc0VGAc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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