SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '16a9af388b8955bec319202c9a0a758f475d5859c552417b6b3cd14f09250a7b' 
  AND token = 'g3+SSrTdl4DSMMideyy1XkXjCMWhm/wV3Ug1VZQuIaI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}