SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '1a1f1ccdf2bd5417f553dae66a8a138f88d840babfdeaa549e1f916dd8bbc74c' 
  AND token = '+VGbBCMId5QczOaSHgHVB/WTG2bWmsWjDhgo3byNLQs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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