SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '616d24c86693e6967c1bb3ac5171097945bf026e7df73ed42b35d940d57bcd27' 
  AND token = 'hqewM41j2h2ZTDzOvmB2FD4ozZSJTWJP0KfYReGPvLs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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