SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '98f0d030473a2af103836b52fd7743e0bd9b883bc62f2607a81474cbad5a8ff6' 
  AND token = '2UyUcQ7wYtUs8WpFkHoZkJWA9U5cqpYjzgw+yPVpD/A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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