SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '12ed511219fea050523ec6fa96a98e61b15090efa1c87807a1c21372c7d63d00' 
  AND token = '3v+63gAlPG8/ZeVCy+WyWbGQ7KS+npi2jKbLM3YBYvM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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