SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e4420ad43686ecaddf71be937aed046262bed45ea858566937e17d9a1dc19f65' 
  AND token = 'XN5baJhDA7ZDp2nYxd1QPTp8rxuuXKWH5e3k1foVrvE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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