SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '33cad819754e71a5a0410dda54558e4b288732734e3b7180a0b0fbe382f16ee3' 
  AND token = 'LANq8auGsspcuCK6VMoP/tu8cJSrGW+SJDFkXhiZtqY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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