SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '492985890259e29a5e237c7aec69fa7ccb8e6adc2701f1cd194c5b13be9d0eb6' 
  AND token = 'uXKYig1xnzL5+UumV0LlHzFdS8IvNWAJBwlB1YpjNks=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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