SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '1545a9a60015a59dac1d35560b7f50d9df1a63e141fdaba009b0c79a23a603e5' 
  AND token = 'PElTfqqR/TQjqeHTvQulMjPWDQvi4N75zieyPCGKYe0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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