SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'acd48c9ff779473a420c59523b6a6ce56ba1fc7ffd4f04d43d52754c83871ebf' 
  AND token = 'QHMSZK4qZWEkha8dnxHJh08dVDYIL0iriHvcgAOcV5Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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