SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3dba2455314995a4df26330ea1fa20cb6a18a513d811bc5d7da257d79b220f3b' 
  AND token = 'm4ZDCAquTIiZjRZMwbkR4OcmXwBKQlf6ov/oL1SK4F0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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