SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '97dc54d3cde164a060c3b7994aa199e9cadda575af413424de5f2205ef83ea88' 
  AND token = 'W38a3csx9iulsrU8cS9udzl6KS3COzdCMo8MJuOCISs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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