SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7d2b6dd36c00f456523c8e578cbdd06e67f75e75ab17853a048a9cb0a540ab87' 
  AND token = 'xwZw/szrTvjhRlN/GP9yeKVLaChBnuLbtljYmC4ZhoU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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