SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bc1ad53d69462b1aed20bd4be69d16f5ed361e7c5a7f764315f7c5da6ee70418' 
  AND token = 'ZqGHfEifqIZAXw4Vvf0oRprPdkvSjrTyq70GsKbthcQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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