SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9c42ee592f19d41fdb0c5fd8ccc2735c21f2f6b1c588db5f50225565fd700ebc' 
  AND token = '69uAzN7Ch75blqZdwTSomWjtccwGL58qfc9BLvQMAJo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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