SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'af43c89e437216ed73e4853d2a0ee9e2bd896eb93f21c94f6fdd0189328ca437' 
  AND token = 'vRPGiHlBpDR74Cxf5wRS2b6cQAs3BuiysCHN9LexFFk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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