SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a5d2374cf637bbbd8ee5826f545fb4a682b817bb6611fa479e05fa157f54c7ae' 
  AND token = '23q8cKpyGTgqF16Uv/ZVFMZNfivc1dyHpUySwEYo/iQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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