SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '69207ba6a435643f8489e18d1399a6fb22538646e1b47487395d7da05891dd3d' 
  AND token = '/thJSNghxKYOAFTPgF2RO4rO3qu7ISr17uXtP00UW7s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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