SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'be17fddcb7649ad6ff5187aee70c6220befa40c39f4989569c0069c9cdf60d91' 
  AND token = 'Pg0z2pFxdm+EIjzIu2WdXt5DqKpSVfNdNtLW454OWhg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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