SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9abf5b5dfdeb47437f5b5d8687128c96c6942367610f05442585845424ac4a52' 
  AND token = '/AkbVKt+SiHSkrpjZ1pIqGt+EhXBeeR6Gv7y4ucMnAU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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