SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '0f83561e925e16b608a1c8b755302e4e922fde38b784efb64f1662f755333b10' 
  AND token = 'aFneQJ7WjWK/WRss3vhHWKxFx06FGytXRjA9vA+pFvc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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