SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '606249193f97a6208325eef75844bc517267f8900ed0a0bac51e21c16853a846' 
  AND token = 'Yx5Xd148q+3Y+Xvq8mZLa1kyjJ7EpK6ThguGki3KG1g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00052

JSON explain

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