SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '13e37e83d42a2142ce1f390a72a9f95a5addaf10111106869e691072e5179cbc' 
  AND token = 'gJ9Y9MDB0IGpK9A51nDa1y+QqndY28v4Bxwef4nIxNc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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