SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ab33ad4e72a1734585762a860227ea001d115befde9e70405f4189524880c220' 
  AND token = 'kc3SUXK+nkTQ0X4zJcQ486vne8UPjKM282GRQ/87i64=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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