SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0299b0a4029a70d65f0c871444cfee45d7fb969188e743e25b13153877f34684' 
  AND token = 'vQ1kK8mm4IB3KB3rKcIPrUiFmDZ8HpCixX+70Kab/No=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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