SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '80a958bb77eb9ce2c8fcd71e4685cd4c34c23d890ce195718f11c32b55e86bd0' 
  AND token = 'cOwqC+ofuJBgPNb7jsOKk/FVWW6HM9AiJDCAucp48es=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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