SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f3e5a1f7161d8d259283d4ad1103f207447133d4f1f9a8c1f6969672d3984179' 
  AND token = '6Cywnwl2PG1xONpCK/iDlbgRbzPcXv3UqHm0LETpXvk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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