SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8228854e2dd46e2f88ffcf1c8e39d748877454686d4ec791cc9b57c1d32b9801' 
  AND token = 'vVf+mu819u6rXdIf2j84r5stkjwvXj7pzQ7voQ3k8rc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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