SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0496ae13bc3974eadef388e86850ec6be63a7c56da0a3be3ad8ce0a9a0390152' 
  AND token = 'kEIpRMKAHdtiHLQ0GCG2gt77j++cCP8dGO7OOhyAvpY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}