SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '665a924b9eb02387270ceb20689286d50fc2db4840f68c19f2a54745e9d8827b' 
  AND token = 'gQqSAZQfLq99uRHmbZ7I/BZ7Yx0kv+h9jw+rrKOJXZY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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