SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '94bc43d114a0a3bc1c0885033a536661ace3207cdfe79045aebedefaf8102040' 
  AND token = 'F4noMlVwCQhXN3h1WZBe9YRqLoakfNkRIIi7dWO6xRk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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