SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '24af36d5168944e41bf1f7a4fb61f20797f5c4c62d7a3110906e81729ac571b3' 
  AND token = 'Kw+JDQfj0mDJLogtaFs+9vtX3jX83cRmNLdVyzaS2II=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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