SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '82cbfe73b7531456a74b4fd91e9ee80b84a9af72dbdbf0065d12266efb89bb7f' 
  AND token = 'bkDqx7oBKV/UbBm5Cv5zLliTbMTaZIGExxhe4wgc1qA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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