SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '42477d01436be54c0882750b547e72af831854d8f8da3984b08cd401d9e5e98b' 
  AND token = 'QHznYDavmWbEqfYWah95tWbYER+zSuYnl/tKEib1txg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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