SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '01d891e1f26d9485151ab4bc0edf4df89853dac64b360509ba79ce525964fc4d' 
  AND token = 'W6oXSWQdry498x/NRKZGeajnRZgqm8GuvJKvI6UV+yY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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