SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0beb836ba3a422cff4293d6da05b4fcb73af441cd4d3da4fff79a3aea7df465d' 
  AND token = 'pTKgeinFRgO2GzRgG5VXnBs408WXAAgjo9SV2VGB/hM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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