SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '62f7391ba76fae6f1b15e02201da4c596eb1dff442755db0117bf7248dc3c96e' 
  AND token = 'hV+agyMAnxEyshJqot/hxFf8wtikjgvtBe3C8sc1EpE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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