SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '22af0a54e185d351e1395167906216d349f39c18a7bfe019ecabfa2e16c63c9c' 
  AND token = 'OXdWTuZ/O5OvriFd2l+vdtYtYrptUINfR2TUF86EHrM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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