SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f3ba4ef8eddd99bd8c84798e56c298ee3531a7b62f75b9391c029d02356f2160' 
  AND token = 'kv1YsXee4kzfUMMp0SInfrKleXsyU1hHWCI5gCpSY2k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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