SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e470b30f375b7a235319b0263d8dbbf63fdb7caf5d58c11084f6522312582a07' 
  AND token = 'KG8g52ZXg+m3l76I7qnD04zXX4ksQXqP+N+pz6vPxLQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}