SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7b3e9b08c6e5afdb898bf1d7506787aacaf3ea3e86c73586eb09180842500f14' 
  AND token = 'siM3QLJgapsegCTpiF2ZoPvDQa26Xx2QwJY8YFmpHXw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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