SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ae083b39c03a3309c19d1832c662f5c5e838917961306b9503a17a3f5903533a' 
  AND token = 'A59Jva57w7/1BNhXvqZ7D3KdtZ7u50V/mlZ7iSnNGoI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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