SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e0b6c2fb4728b93f701b8f8de90be1f2479baf779caf69cb7422ba39f78aaa6e' 
  AND token = 'euZve6r1u2cmehV0PAwyflGVsEArXHZLg4LZjLIWj10=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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