SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '60d628c4fd49251bdbc1afed1b574f1746255be6361e88890ea253867ad65b5b' 
  AND token = '8VtuHZrecEB5JIHND7zbvTbpZVbt8uEfmAwCYstxXgc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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