SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3614f0aa9fe1d343ac8e4157e8c28e494948e1dd775fb50b969cd41ea73ef88f' 
  AND token = 'vbZTyaa1AVxyILuk/GY6BL4188H+NHcwk0RmhpBg5Cs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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