SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f527e7a5e22ec199f094d21a90f4a9e053b4e37f45c3e415a9dcdd9b23e16a28' 
  AND token = 'qUCM3vBwUKBQu8Z8tGNE7VFlcc+HZXp39FELz2+qb5I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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