SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '1b8c79f33313ac1c2a00b4d76779c91b7cc031b032d4c820e7f45febf1571161' 
  AND token = 'kvYu+ZSyUeJ6Zv2opxxuCzMM5cao7JXxPh6Wf/Ravzw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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