SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd0cb8c2fe7248244ea26ab9aa50a0178e4f33f4882d6186bbb024baeadaec353' 
  AND token = 'y8x5mq9KspQZhIqbeTi1zpW1l1Q6fKMDePJrQ9oNwkg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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