SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '153c57019c2c008cfb7248803df56368dbb17e33155cc90ef5839ef56ba3657b' 
  AND token = 'NsVpCAXjprrzBYVBUSio2/BuILwKYJxrUPfgLI3jcic=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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