SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8abf5228c296a37c538bb2b20b8a64cb6e18d99346c60d022076434c36e6e369' 
  AND token = 'ssbNTGwxvophN/V3SaTFz6K5mEAOXFHxpAKj+uFgJ9I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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