SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '66ed056930242b7cd7d2ae0abe583dfa1011429fbc4b49cd8b895d1e4ab3f332' 
  AND token = 'D6DpqEzi7oEOrt/p2wCX+XPvne6S9K9ZAw5F+qUfPQI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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