SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9550a239190f4ee452fedd4c6a0c805023269931e8332309011b1c81b233091d' 
  AND token = 'uio45aYjw0IW187ARrrwPdb0olU283a2jwXImWxXJOA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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