SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9fc906c3d9cb067c749fba95586b04fd4cdcb3ecc16e05c6c25d2b9360a18830' 
  AND token = 'ULiImFLrey3EbeYrzsX5vrxYAy1QQxfcAAbb2NvO/D8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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