SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '67d1f679ba5a006b8af117cb640266558eff84f90a9f412fa407244d5354d17e' 
  AND token = '7lpHAhCaMbBVVJHreG0UwErnif/y57nCkYin6Up8Zb0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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