SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '042186f7dbecfde24ba950d819555a81a883ccc9d246bb8c1f5e87e184dc01b8' 
  AND token = 'Yd/zLNRE5hmyZOufSTLiXndeUSd0C+yitAzS3s64+pw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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