SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6917a2734bdb6c5082f4eeb8436265356032493665c0a3d0a5fc200cbe858819' 
  AND token = 'fCQU/zdbYd7GlUVhreOr9l+DWvD/zXmLOhr9hjt2o3g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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