SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '095e642ad590ca0196310215f75d90ae16603d52d4c88a0df23d949094ee0999' 
  AND token = 'TXSRG9mbb0IvTcTZcC9cAyTvUloiyQc5f3FuMkPVU34=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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