SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '288cc193651b65461c3de7720b744954ae9780fec852478b5a305ab39391be34' 
  AND token = 'OD+DQI8RwoytmWuhUh3zq/X9cG2t7wmXG8iKKIlRIVg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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