SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4f6a55ecb189198fe2e1719b3af7f2ed8806c45447730782aeaa1e7bc0eea66e' 
  AND token = 'CLt+2w/yLkmMH+PV5WnmDYXSjKV3YsGnuMw1wAzla7o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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