SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2d70621b46f748f1b886bb0e807ced898b3a4d0226d1af745cf75f27a62d47ef' 
  AND token = 'akA8zcWw3UsMbqEFQfFYQQyaxxqf/M9uFpvigahJVF4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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