SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c2152f87c4aa9e6c87d0662f427bff81391ce8c8db8615aa9942df56418fa35b' 
  AND token = 'nbR8+sTDWrtkZSPfQ+yFIbrAL5PVrcIzcHJ/xo6XZPw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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