SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '10ce67cbc895eaa930d784b1158345aae3272a28ad88aad51aa36c9e49542fcd' 
  AND token = 'fsDCBUwEH/lCeHXQYSzjjknZLsSg6+lR5qlewAAgtnw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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