SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6e95bf5044b3c86ef95290943d48280c06b556cccfb0ba023a871149f9878f79' 
  AND token = 'Ka4ZZwdPthFIvpz0iYHLRJyYK0jHpaE9DaI3kkWmdsE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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