SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '13890dd4afc7e653d7b18f90ed5f95f4f595bb0273ceb904d51d2028a6dd306a' 
  AND token = 'VJOcAx4IlBYV959XNK0cLXp3bP5gZMb1oNFkvMoieYQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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